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Table of Contents
Foreword
Preface
Glossary

Chapter 3: Geologic Structure and Landforms

Introduction

Geologic interpretation of images begins with the identification of lineaments, “regional linear features caused by linear arrangement of regional morphological features such as streams, escarpments, and mountain ranges and tonal features that in many areas are the surface expressions of fractures or fault zones.”[i] The emphasis in this section is on geologic structures and landforms, both of which can be easily identified on air photographs and other images.

The sequence followed here is that often found in geomorphology books. Geologic structures and structurally controlled landforms are illustrated first, followed by images of mass wasting and of the results of the agents of erosion—running water, ground water, ice, wind and the sea. The meandering rivers of southern Manitoba are excellent examples of that river form. Several of them have deposited deltas into lakes. The effects of ground water are less easily illustrated, but examples of spring sapping and artesian erosion exist in the south. As all of Manitoba was covered by ice during the latest glaciation, examples of glacial erosion, and especially of glacial deposition, are widespread. Equally impressive are the suite of landforms created by the large glacial lakes that appeared as the ice melted. Glacial spillways, glacial lake deltas, strandlines and flat lake floors are found in many places. Wind action has created dunes on some of the deltas and on glacial outwash deposits. The Hudson Bay coast is rising as a result of isostatic rebound, recovery from the weight of the ice. One result is the existence of strandlines many metres above the level at which they were created. Finally Manitoba’s great lakes are large enough to illustrate many of the landforms normally associated with sea coasts.



Notes

[i] Lillesand, T. M. and Kiefer, R. W. Remote Sensing and Image Interpretation (Third Edition). New York: Wiley, 1994, 179.

3.1: Structures in the Precambrian Shield Near Snow Lake

This area is located within the Churchill Province of the Precambrian Shield, north of Snow Lake. Compton Lake 1 is located in the northwest, branches of Squall Lake 2 and McLeod Lake 3 are located in the southwest, Angus Bay 4 off Herblet Lake and Wolverton Lake 5 are located in the southeast, Stack Lake 6 is located in the northeast, and Zoratti Lake 7 in the north. The rocks in this area “can be considered for simplicity, as banded gneiss in its many forms.”[i]. Gneiss is a metamorphic rock formed by compressing and heating of the pre-existing rocks. Tectonic activity has produced a series of folds, and differential weathering and erosion of the rock layers of varying resistance has resulted in ridges and valleys that reflect the structure. A dome can be recognized at 8 and an auticline (up fold) at 9. “The lighter grey-toned irregularly shaped rock body at 10 is probably a lens of pegmatite.”[ii] The shapes of some of the lakes, especially Wolverton Lake 5 and Zoratti Lake 7, are clearly influenced by the structure.

Figure 3.1: Structures in the Precambrian Shield Near Snow Lake

Figure 3.1: Structures in the Precambrian Shield Near Snow Lake

Figure 3.1

Vertical air photograph: A14982-52

Flight height: 30,000 feet a.s.l.: lens focal length: 152.91 mm

Date: June 14, 1955

Scale: 1:59,500 (approx.)

Location: Townships 69 and 70, Ranges 16, 17 and 18WI

Map Sheets: 1:250,000 63J Wekusko Lake

63K Cormorant Lake

63N Kississing Lake

63O Nelson House

Notes

[i] Mollard, J. D. and Janes, J. R. Air Photo Interpretation and the Canadian Landscape. Ottawa: Energy Mines and Resources Canada, 1984, 22.

[ii] Mollard and Janes, op. cit. 24.



3.2: Structures in the Precambrian Shield Northwest of Snow Lake

This area is located just west of that shown in figure 3.1. Two domes are located at 1 and 2, the latter being picked out by the shape of Gudy Lake 3. East/west trending rocks can be seen at 4, and faulting has produced the two linear features at 5 and 6. A very light-toned massive body of granite rock or pegmatite can be seen at 7, southwest of Styne Lake 8.[i] The light-toned line at 9 is the path of a power transmission line between Snow Lake and Sherridon, two northern mining communities.

Figure 3.2: Structures in the Precambrian Shield Northwest of Snow Lake

Figure 3.2: Structures in the Precambrian Shield Northwest of Snow Lake

Figure 3.2

Vertical air photograph: A14982-49

Flight height: 30,000 feet a.s.l.: lens focal length: 152.91 mm

Date: June 14, 1955

Scale: 1:59,600 (approx.)

Location: Townships 69 and 70, Ranges 18 and 19 WI

Map sheets: 1:250,000 63K Cormorant Lake

63N Kississing Lake

Notes

[i] Interpretation of the structure is from Mollard and Janes. op. cit., 24.



3.3: Folded Structures in Precambrian Sedimentary and Metamorphosed Sedimentary Rocks North of Snow Lake

In this area there is a close relationship between structure and topography, the various folds forming a series of ridges and valleys resulting from differential erosion of the various layers. Compton Lake 1 “lies in the trough between a domelike fold in the west 2 and the Herblet Lake Gneissic Dome to the east”3.[i] Radial joints on the west side of the latter result in lines of weakness which have been exploited by weathering and the agents of erosion to produce low-lying areas which are partially filled with surficial deposits 4. A small anticline bounds Compton Lake on its southwest side 5. Snow Creek 6 exits Compton Lake southwards to Squall Lake (which is shown on figure 3.1).

The tonal variations in the lakes vary from very dark grey (Drysdale Lake 7) to almost white at the south end of Compton Lake, the light tone resulting from the relationship between water surface, sun angle and camera lens, to give specular reflection.

Figure 3.3: Folded Structures in Precambrian Sedimentary and Metamorphosed Sedimentary Rocks North of Snow Lake

Figure 3.3: Folded Structures in Precambrian Sedimentary and Metamorphosed Sedimentary Rocks North of Snow Lake

Figure 3.3

Vertical air photograph(s): A13398-129

Flight height: 16,700 feet a.s.l.: lens focal length : 151.65 mm

Scale: 1:32,000 (approx.)

Date: July 8, 1952

Location: Township 70, Range 18 WI

Map sheets: 1:250,000 63N Kississing Lake

1:50,000 63N/1 Nightingale Lake

Notes

[i] Mollard and Janes. op. cit., 24.



3.4: Structural Features on the Precambrian Shield Southwest of Shamattawa

The photograph shows part of the poorly drained Precambrian Shield in northeastern Manitoba. In this area the bedrock is mapped as “felsic granulites and associated granitoid complexes with minor gabbro and anorthosite”[i] but organic surficial materials cover most of it. North Opuskiamishes Lake 1 at 137+ metres above sea level[ii] drains via North Opuskiamishes River 2 to Gods River (off the photograph). The course of the former river is structurally determined with a right-angled bend at 3. Other obvious structural lines can be seen at 4, 5, 6 and 7 with less clear examples at 8 and 9 and a complex of joints at 10. The pattern at 11 surrounding a small lake results from strings of vegetation separated by pools of water. The variable tones of the lakes on this photo result from variations in the lake surface/sun angle/camera lens relationship. However, the light tone at 12 in North Opuskiamishes Lake is caused by sediment washed in by a river.

This is the first photograph in a series (contract 711) and the specifications for the job are given in the top left-hand corner 13. The photographs were obtained from a height of 30,000 feet above sea level using a camera with a focal length of 6 inches with a Wratten no. 12 filter. Flight lines were from north to south (photo numbers 1 to 36), south to north (photo numbers 37 to 66), etc. Using the information provided it is possible to calculate the scale of the photograph using the equation f/h=i/o where f=focal length of the camera; h=height of the camera above ground level; i=image distance, that is, the distance between two objects on the photograph; and o=object distance, the distance between the same two objects on the ground. In effect i/o is the scale of the photograph. When doing the calculation, f and h must be expressed in the same units. So in this case

f=6 inches or 0.5 feet

h=30,000-449 (the height above sea level of North Opuskiamishes Lake on the 1:250,000 topographic map, 53 N Gods River).

So the scale is 0.5/29,551 or 1/59,102

The scale is 1:59,000 approximately—allowing for height variations within the area covered by the photograph.

Figure 3.4: Structural Features on the Precambrian Shield Southwest of Shamattawa

Figure 3.4: Structural Features on the Precambrian Shield Southwest of Shamattawa

Figure 3.4

Vertical air photograph: A14215-1

Flight height: 30,000 feet a.s.l.; lens focal length 6 inches

Date: July 7, 1954

Scale: 1:39,000 (approx.)

Location: Township 76, Ranges 9 and 10 EI

Map sheet: 1:250,000 53N Gods River

1:50,000 53N/10 East Niska Lake

Notes

[i] Geological Survey of Canada. Geological Highway Map of Manitoba 1994. Winnipeg: Geological Survey of Canada, Manitoba Minerals Division, 1994.

[ii] From NTS 1:250,000 map, 53N Gods River, 1987.



3.5: Structural Control of Drainage East of Lake Winnipeg

This satellite image shows an area east of Lake Winnipeg 1 that is seen in the southwest corner. The area is part of the Canadian Shield and is underlain by Precambrian rocks in which fractures are exploited by drainage lines, for example, the Bloodvein River 2. The river has a series of straight stretches 3 and some sharp angular bends 4. Its course includes many rapids and waterfalls.[i] The Leyond River 5 that joins from the east also has structurally determined straight stretches 6. Other fracture zones, with no obvious drainage, can also be seen 7. The Bloodvein is generally regarded as one of the great canoe routes in Canada. “In 1985 the government of Manitoba designated a 4,000 square kilometre area east of Lake Winnipeg, including the Pigeon (north of the area shown) and Bloodvein watersheds, as the province’s first wilderness-class park. Six years later, the Bloodvein received its prestigious designation as a Canadian Heritage River for its significance in terms of human history and natural heritage, and for its potential for wilderness tourism.”[ii] The Bloodvein, which flows from Ontario into Manitoba, is famous for pictographs found at cliff sites along its route. However, the only evidence of human activity on the image is a light-toned zone 8, which is the route of a power line.

Figure 3.5: Structural Control of Drainage East of Lake Winnipeg

Figure 3.5: Structural Control of Drainage East of Lake Winnipeg

Figure 3.5

Google Image 2006 Terra Metrics

Scale:

Location: Townships 30 and 31; Ranges 7 and 8E

Map sheets: 1:250,000 62P Hecla

Notes

[i] For details see, Wilson, H. and Aykroyd, S. Wilderness Rivers of Manitoba. Merrickville, Ontario: Canadian Recreational Canoeing Association, n.d., 47-54.

[ii] Wilson, H. and Aykroyd, S. Wilderness Manitoba: Erin, Ontario: Boston Mills Press, 1999, 57.



3.6: Fault Scarp on the Precambrian Shield Northwest of Wabowden

The rocks in this part of the shield are mapped as “highly metamorphosed and partly migmatic derivative”,[i] but, as in the case of figure 3.4, they are mainly covered by surficial material. A striking linear feature trending north-northeast to south-southwest with a 26-degree bend at its southern end breaks the monotony of the topography 1. This is interpreted as a “fault scarp, post glacial”[ii] with the downthrow side to the southeast. The feature peters out in the south, but two other linear features at 2 and 3 seem to be a continuation of the same structure. A small meandering stream developed on the surficial material that offers uniform resistance to erosion crosses the area from north-northwest to south-southeast 4. In the southwest are extensive areas of string bog 5—strips of vegetation separated by water—that are perpendicular to the general slope of the land to the southeast. The string bog surrounds lenses of highland covered by coniferous trees 6. Streamers of light tone at the southern ends of the lenses 7 indicate slow movement of land to the southeast.

Figure 3.6: Fault Scarp on the Precambrian Shield Northwest of Wabowden

Figure 3.6: Fault Scarp on the Precambrian Shield Northwest of Wabowden

Figure 3.6

Vertical air photograph: A14982-154

Flight height: 30,000 feet a.s.l.; lens focal length: 152.91 mm

Date: June 14, 1955

Scale: 1:58,000 (approx.)

Location: Township 70, Ranges 11 and 12 WI (southern two thirds of photo)

Map sheets: 1:250,000 630 Nelson House

1:50,000 630/3 McNeill Lake

Notes

[i] Geological Highway Map of Manitoba. 1994.

[ii] Bostock, H. S. A Catalogue of Selected Airphotographs. Ottawa: Geological Survey of Canada, Paper 67-48, 1968, 66.



3.7: Bedrock Plateau North of Grand Rapids

This air photo shows carbonate rocks (limestone, dolomite) and discontinuous shallow wave-modified till over flat-lying carbonate rocks.[i]

Silurian rocks of the Interlake Group underlie a plateau—the Mamowkiyan Ridge—1 whereas Ordovician rocks underlie the marshy land to the west 2. The large water body, Melhiso Lake 3, drains by Eating Point Creek 4 to the west shore of Lake Winnipeg 5 north of Eating Point Creek 6. Beach ridges created when Lake Winnipeg was at a higher level outline the eastern and northern edge of the plateau 7. In the south is the large Saskatchewan River 8 shown emptying into Lake Winnipeg before the construction of the Grand Rapids Dam in the area.

Figure 3.7: Bedrock Plateau North of Grand Rapids

Figure 3.7: Bedrock Plateau North of Grand Rapids

Figure 3.7

Vertical air photograph: A13935-52

Flight height: 35,000 feet a.s.l.; lens focal length: 152.15 mm

Date: October 28, 1953

Scale: 1:68,000 (approx.)

Location: Township 49, Range 13 WI (Part of Grand Rapids, Local Government District)

Map sheet: 1:250,000 63G Grand Rapids

1:50,000 63G/3 Grand Rapids

Notes

 

[i] Information from Mollard, J. D. Landforms and Surface Materials of Canada (Third Edition). Regina: Commercial Printers, n.d., plate 12 18b.

 



3.8: Joint Zones South of Lamb Lake

Often vegetation obscures the bedrock geology, but in some cases the vegetation is a reflection of the geology. The photo shows an area of flat, mainly wooded land between South Moose Lake and Cedar Lake in central Manitoba. “Lines of trees disclose the location of joint zones (joint zones are numerous closely-spaced individual parallel and on echelon joint planes, which, because of their number and close spacing are accentuated by longtime weathering and erosion). Because the closely spaced joints weather and erode differentially in flat-lying Silurian dolomite terrain, they offer a better environment for growing trees than nearby areas where the joints are widely spaced.”[i] Two prominent lines of joint zones trend west-northwest/east-southeast 1 and northeast/southwest 2 intersecting at a 45° degree angle 3. Part of the south shore of Lamb Lake 4 coincides with the west-northwest/east-southeast trend. In the northwest is Ranchers Creek 5.

Figure 3.8: Joint Zones South of Lamb Lake

Figure 3.8: Joint Zones South of Lamb Lake

Figure 3.8

Vertical air photograph: A19767-87

Flight height: 8,920 feet a.s.l.; lens focal length: 152.16 mm

Date: September 16, 1966

Scale: 1:16,500 (approx.)

Location: Township 54, Range 19 WI

Map sheets: 1:250,000 63F The Pas

1:50,000 63F/9 Lamb Lake

Notes

[i] Mollard, op. cit., plate 10.19a



3.9: Escarpment North of Grand Rapids

In this area west of the north end of Lake Winnipeg, southwest of Buffalo Lake the junction between Ordovician rocks to the east and Silurian rocks to the west is marked by a prominent escarpment 1 with a major westward embayment 2. Water percolates down through the Silurian carbonate rocks to emanate from the base of the escarpment giving rise to a series of eastward flowing rivers 3. White patches 4 are probably sinkholes, whereas lakes 5 are dark in tone. Curvilinear lines along the face of the escarpment 6 mark former high levels of Lake Winnipeg, just off the photo to the east. Deciduous trees cover most of the area, and there is little obvious human impact except for a few forest trails, one of which follows the face of the escarpment 7.

Figure 3.9: Escarpment North of Grand Rapids

Figure 3.9: Escarpment North of Grand Rapids

Figure 3.9

Vertical air photo: A25997-198

Flight height: 9,920 feet a.s.l.; lens focal length: 152.034 mm

Date: June 25, 1982

Scale: 1:18,400 (approx.)

Location: Township 51, Range 13 WI

Map sheets: 1:250,000 63G Grand Rapids

1:50,000 63G/6 Eating Point


3.10: The Riding Mountain Escarpment

The area shown can be divided into three landform regions: in the west the Riding Mountain Plateau 1; in the centre, the Riding Mountain Escarpment 2; and in the east the Manitoba Lowlands 3.

The plateau has a low amplitude of relief—no more than about 100 feet (30.5 m)—its rolling surface being developed on a thick layer of till overlying Cretaceous age shales. At no place is the bedrock visible. A zone of lakes, from north to south—McKinnon Lake 4, Rowland Lake 5, Campbell Lake 6, Watson Lake 7, and Muskrat Lake 8—follow a line of weakness along the north/south strike of the Cretaceous rocks. Muskrat Lake’s light tone suggests that it contains suspended sediment whereas the others—dark-toned—do not. All the named lakes drain to the west by a series of slow-flowing streams. Most of the plateau is covered by mixed coniferous/deciduous woodland, but poorly drained marshy areas also exist 9, ideal moose habitat.

The escarpment drops over 900 feet (274 m) to the east in less than three miles (five km). It is deeply dissected by many small creeks 10 that have eroded into the shale after removing any overlying till. Bedrock appears as light-toned patches on the valley sides; for example, on both sides of Bald Hill Creek 11. The streams are susceptible to flash floods causing both flooding and the deposition of shale on the fields at the escarpment’s base. Low angle alluvial forms—too low an angle to pick out on the photograph—have coalesced to form an apron between the escarpment and the lowlands. In some cases strong subsequent streams flowing north/south along the strike 12 have captured consequents flowing down the escarpment. Apart from a few steep valley sides the whole escarpment is covered by mixed coniferous/deciduous woodland.

The lowlands are underlain by rocks of Jurassic age overlain by till and glaciolacustrine sediments deposited into glacial Lake Agassiz. Several prominent strandlines can be seen, some of which are named: the Herman 13, the highest, the Norcross 14, and the Campbell 15. They show up principally as a result of land use differences, the Herman, for example, delimiting the eastern edge of the woodland 16. Most lowlands have been cleared for agriculture but fingers of woodland extend along creek courses. It is noticeable that several creeks terminate at the Campbell shoreline 17.

Culturally the area can be divided into two parts. The mainly wooded plateau and escarpment lie within Riding Mountain National Park where woodland clearing is prohibited. In the north the edge of the woodland coincides with the park boundary, but in the south the woodland extends beyond the park 18. In contrast the lowlands have been divided up according to the Dominion Lands Survey (DLS) system. Individual sections (1 square mile) 19 and quarter sections 20 can be seen and gravel roads 21 run east/west and north/south along section lines. The only paved road— PTH 5—diverges from the DLS system in the south 22 but follows section lines further north 23. PTH 19, where it crosses Riding Mountain National Park, is outside the DLS system and includes, what for Manitoba is a rarity, three hairpin bends as it descends the escarpment 24. Forest trails—part of the park’s hiking and ski trail system—can be seen (25 and 26). A CN railway line 27 runs through Kelwood 28, the only nucleated settlement in the area. In contrast to many prairie towns and villages, the orientation of its roads are based not on the railway line but on the north/south and east/west lines of the DLS system.

Figure 3.10: The Riding Mountain Escarpment

Figure 3.10: The Riding Mountain Escarpment

Figure 3.10

Vertical air photograph: A21808-32

Flight height: 24,400 feet a.s.l.; lens focal length: 85.55 mm

Date: August 6, 1970

Scale: 1:81,000 (approx.)

Location: Townships 18 and 19, Range 15 WI and part of Riding Mountain National Park

Map sheets: 1:250,000 62J Neepawa

1:50,000 62J/12 Wasagaming

1:125,000 MCR 207 Riding Mountain National Park


3.11: The Crawford Creek Embayment in the Riding Mountain Escarpment

Where it trends north/south or north-northwest/south-southeast (south of the Mount Agassiz ski hill), the Riding Mountain Escarpment is dissected by narrow, steep-sided, v-shaped valleys. Further north where the trend is northwest/southeast, two creeks, Ochre Creek and Crawford Creek, have created deep embayments in the scarp face. Shown here is the embayment 1 produced by the northeast flowing Crawford Creek 2 that rises on the plateau at about 2,300 feet (701 metres) above sea level 3. Another stream, unnamed 4, flows off the plateau to the northwest with three other small valleys 5 leading to the north. In the south is a stream 6 that flows to Ochre River (off the photo to the southeast), and two other small streams 7 flow roughly parallel to Crawford Creek. The gently dipping (to the west) Cretaceous bedrock has been eroded into a series of terraces running parallel to the escarpment 8 and into the Crawford Creek Embayment 9.

Nearly all the area is covered by mixed woodland with more uniform dark-toned patches 10 representing stands of coniferous trees.

Figure 3.11: The Crawford Creek Embayment in the Riding Mountain Escarpment

Figure 3.11: The Crawford Creek Embayment in the Riding Mountain Escarpment

Figure 3.11

Vertical air photograph: A15229-20

Flight height: 17,140 feet a.s.l.; lens focal length: 152.4 mm

Scale: 1:34,000 (approx.)

Date: June 4, 1956

Location: Township 22 and 23; Range 18 and 19WI

Map sheets: 1:250,000 62J Neepawa

1:50,000 62J/13 Laurier

1:125,000 MCR 207 Riding Mountain National Park

 


3.12: Landforms of Southwestern Manitoba

At first glance three dark-toned areas stand out: in the south, straddling the Canada/U.S.A. border, is Turtle Mountain 1; in the northeast is the Assiniboine Delta 2; and in the west is another area underlain by glaciolacustrine deposits with Oak lake 3 at the centre.

Turtle Mountain is dark-toned because it is mainly covered by woodland that contrasts with the light tones of the surrounding agricultural land. The international border across Turtle Mountain 4 stands out because more woodland has been cleared south of the border. The sharp northern edge of the woodland 5 is the boundary of Turtle Mountain Provincial Park in which little clearing has occurred.

The Assiniboine Delta, deposited into glacial Lake Agassiz, is not so uniformly dark-toned because the land cover varies. In the north and west rectangular agricultural fields can be seen 6. The darkest-toned areas are tree covered with aspen (Populus tremuloides), white spruce (Picea glauca), black spruce (Picea mariana), and tamarack (Larix laricina). One such area at the northern edge of the delta 7 follows a former course of the Assiniboine, a route that is now occupied by Epinette Creek. A very light-toned patch at the east side of the delta is the Bald Head Hills 8, an area of active sand dunes. The meandering Assiniboine 9 follows the southern edge of the delta.

The third dark-toned area is also a result of deposition into a glacial lake, but not in deltaic form. Again the land cover is varied, resulting in tonal variations: very dark-toned areas are woodland 10, less dark areas are grass covered 11, and some patterned cropped areas can also be seen 12.

The main upstanding areas are Turtle Mountain, a drift-covered Tertiary outlier which rises 700 feet (213 m) above the surrounding land, and two areas of end moraine, the Brandon Hills 13 and the Tiger Hills 14, both of which are part of the Darlingford moraine that extends across much of southwest and south central Manitoba. The dark-toned Brandon Hills are still largely wooded but more land has been cleared for agriculture in the Tiger Hills.

Two major river valleys of the Assiniboine 15 and the Souris 16 are the main areas of negative relief. West of Brandon, the Assiniboine flows in a glacial spillway 17 that carried water from glacial lakes in Saskatchewan to glacial Lake Agassiz, depositing the Assiniboine Delta in the process. The spillway is steep-sided with a flat floor approximately one kilometre across. It is best seen where it runs east/west 18 with a dark shadow on the south side. Also contributing to the dark tone is the fact that the south side, which enjoys a wetter microclimate, is wooded. The north side, facing into the sun, is drier and consequently supports less woodland.

Two former courses of the Assiniboine can be seen, one north and the other south of the present channel. To the north is a moderately dark-toned area 19. Probably the Assiniboine split and flowed on both sides of this almond-shaped area. To the south is a dark-toned area of lakes and marshes 20 now 200 feet (61 m) above the level of the Assiniboine. This route may have been followed by a proto-Assiniboine, flowing along the edge of the last ice sheet that covered the region. Below Brandon the valley loses its spillway form as it starts to flow across the Assiniboine delta.

The Little Saskatchewan River 21 joins the Assiniboine just above Brandon. Its valley is not a spillway, but it is much larger than the present flow of the river warrants, probably due to a large volume of water flowing from the Riding Mountain Uplands (off the image to the north) as the glaciers melted.

The Souris River enters southwest Manitoba from North Dakota. At the border it occupies a shallow spillway 22 that braids into several channels to the north 23. Farther northeast it opens out, and at Souris 24 it turns southeast and once again occupies a spillway-shaped valley 25. This spillway continues southeast and is occupied by a sequence of lakes: Bone Lake 26, Pelican Lake 27, Lorne Lake 28, Louise Lake 29, and Rock Lake 30. The Souris used to follow this route along the southern edge of the Tiger Hills moraine, but it now makes a 90-degree bend to cut through the Tiger Hills in a gorge 31 to join the Assiniboine below Wawanesa. This bend has been interpreted as an elbow of capture.

Southeast of the present Souris River is a valley only partly occupied by water—the Dand Spillway 32—that probably originated as an ice marginal channel.[i]

In addition to the lakes already named, Whitewater Lake 33 is located at the centre of a basin of inland drainage north of Turtle Mountain. The lake is intermittent; in wet years—which 1973 must have been—it is water filled, but in dry years such as the early 1980s it is almost completely dry. It is light-toned compared to Pelican Lake because of sediment stirred up in the shallow water. Numerous small lakes, very dark-toned, occupy hollows in the ground moraine on Turtle Mountain 34.

Human Impact

Much of the area exhibits the typical checkerboard pattern of the DLS system. The system dictates the road pattern with roads mainly following section lines running east/west or north/south. Roads show up most clearly where they cross wooded land, for example, PTH 10 across Turtle Mountain 35, PTH 5 across Spruce Woods 36, and Trans Canada Highway in the northeast corner of the image 37.

Brandon, the only city on the image; shows up as a light-toned patch 38, but the other small towns and villages in the region are not visible because the land cover is similar to that in the surrounding countryside. The airfield at Rivers 39 is very prominent but surprisingly Brandon airfield north of the city is not.

Reservoirs behind dams are obvious, particularly Lake Wahtopanah 40 northeast of Rivers and Upper Des Lacs Lake on the Souris River just south of the international border 41.

Figure 3.12: Landforms of Southwestern Manitoba

Figure 3.12: Landforms of Southwestern Manitoba

Figure 3.12

Skylab image: September 19, 1973

Scale: 1: 670,000 (approx.)

This is a photograph obtained from the Skylab spacecraft, one of the first “manned” satellites from which earth images were obtained.

Notes

[i] Brown, W.J. “Geography field excursion to southwest Manitoba.” in Field Guide for the Canadian Association of Geographers Annual Meeting. Winnipeg: University of Manitoba, Geography Department, June 1970, 43-71.



3.13: Slumping: Souris Gorge Between Souris and Wawanesa

East of Souris the southeastward flowing Souris River takes a right-angled bend to flow northeast 1 through the Tiger Hills moraine in a gorge. The river’s long profile in this area is unusually steep with occasional rapids (2, 3, and 4). The river has incised itself through the surficial glacial deposits and into the underlying Cretaceous shales that appear as light-toned areas on the valley sides 5, 6. Coupled with vertical incision has been lateral movement toward the outside of river bends, leaving behind scars of former higher positions 7. Erosion on the outside of a bend has resulted in a major slump 8 and a smaller one 9. The larger slump flattens the river’s course between two points (10 and 11). The slumped area dams a small south bank tributary 12 to produce a small lake 13.

The valley sides and the hummocky land 14 of the Tiger Hills are covered by deciduous woodland except for some areas cleared for cattle grazing 15. This contrasts with the flat land south 16 and north 17 of the valley that has been cleared for agriculture. These areas are underlain by glacial deposits, and to the north very minor northeast/southwest trending ridges 18 are picked out by the rain splash effect: rain splashes small-sized, dark-coloured fragments from crests, leaving behind coarse light-toned materials. To the west water-filled hollows 19 emphasize this topographic pattern.

Figure 3.13: Slumping: Souris Gorge Between Souris and Wawanesa

Figure 3.13: Slumping: Souris Gorge Between Souris and Wawanesa

Figure 3.13

Vertical air photograph: A11046-57

Flight height: 9,520 feet a.s.l.; lens focal length: 6 inches

Date: May 21, 1947

Scale: 1:15,800 (approx.)

Location: Township 6, Range 18 WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/12 Wawanesa


3.14: Slumping in the Pembina Valley South of Darlingford

At the end of the Wisconsinan ice age, the Pembina Valley carried water from glacial Lake Hind in southwest Manitoba to glacial Lake Agassiz. The water eroded a valley currently over 300 feet (91 m) deep that is now occupied by the misfit Pembina River 1. It is joined from the northeast by a small creek 2, which has etched a deep, v-shaped valley that breaks the continuity of the northeast wall of the spillway. The southwest wall is more continuous and very steep: undercutting by the Pembina has resulted in slumping leaving behind slumped blocks 3 with a dried-up slough in the depressions between the blocks 4. The Pembina meanders on the spillway floor depositing light-toned gravels in many locations 5. A small creek enters from the west 6. The Pembina has abandoned two river segments 7: one cutoff 8 is very recent and another is imminent 9.

The southwest spillway wall, the valley of the northeast creek, and parts of the northeast spillway wall are all wooded (deciduous). Flat lands outside the valleys and some terraces on the northeast spillway wall 10 have been cleared for agriculture. One gravel road 11 and several paths 12 can be seen as well as three farms 13, all of which have shelterbelts to the north and west 14. A dugout 15 is located close to one farm.

Figure 3.14: Slumping in the Pembina Valley South of Darlingford

Figure 3.14: Slumping in the Pembina Valley South of Darlingford

Figure 3.14

Vertical air photograph: A16181-172

Flight height: 10,500 feet a.s.l.; lens focal length: 152.63 mm

Date: July 20, 1958

Scale: 1:18,100 (approx.)

Location: Township 1, Range 7 WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/1 Morden


3.15: Incised Meanders and Slumping: Souris River at Wawanesa

Downstream from figure 3.13 the Souris River valley exhibits classic incised meanders. Here the river channel is over 100 feet (30.5 m) below the flat surrounding countryside that has been cleared for agriculture (1 and 2). As incision took place the river continued to erode laterally, leaving behind scars (3 and 4) on the insides of bends and steep cliffs 5, 6 and 7 on the outsides. The river is incised into glaciolacustrine deposits overlying till which in turn overlies the Cretaceous shales that in the field can be seen at the bases of the river cliffs. Erosion has resulted in a large slumped mass 8 that deflects the river course. Slumping continues particularly where a monument to the explorer/cartographer Thompson is now located well down the valley side several metres below the point at which it was erected 9. This 1945 photograph shows a road at the top of the cliff (between 10 and 11); now much of it has disappeared over the cliff top. Talus of fallen material causes a minor deflection in the river’s course 12. A small south bank tributary has produced a gully 13, and nearby clearing for agriculture has resulted in rain splash erosion of the gully side producing white patches 14.

Figure 3.15: Incised Meanders and Slumping: Souris River at Wawanesa

Figure 3.15: Incised Meanders and Slumping: Souris River at Wawanesa

Figure 3.15

Vertical air photograph: A11123-310

Flight height: 17,300 feet a.s.l.; lens focal length: 6 inches

Date: September 25, 1947

Scale: 1:35,000 (approx.)

Location: Township 7, Range 17 WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/12 Wawanesa

 


3.16: Slumping in the Souris Valley Below Wawanesa

In the area of Wawanesa, the meandering Souris River has incised itself down through surficial glaciofluvial and glacial deposits into the underlying Cretaceous shales. These two photographs illustrate the value of sequential air photos (photos taken of the same area at different times) in documenting changes even in the case of relatively slow changes such as those caused by geomorphological processes.

a)  1945 photo: Incised meanders of the Souris River can be seen with river cliffs on the outside 1 and slip-off slopes on the inside 2 of bends. Lateral erosion by the river has resulted in slumping at two locations 3, but east of Wawanesa the south bank 4 appears to be stabilized by thick woodland.

b)  1981 photo: This photo shows the course of the Souris 1 and a very clearly defined abandoned meander 2 still with some water in it but now well above the river level. Slumping has occurred on the south side of the river 3 since the 1945 photo was taken. The slump has a steep back wall 4 and an irregular main body 5 that causes a slight northward bulge of the river channel. 

Figure 3.16.a: Slumping in the Souris Valley Below Wawanesa, 1945 photo

Figure 3.16.a: Slumping in the Souris Valley Below Wawanesa, 1945 photo

Vertical air photo: A11123-309

Flight height: 12,400 feet a.s.l.; lens focal length: 8 inches

Scale: 1:17,000 (approx.)

Date: 1945

Location: Township 7, Range 17 WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/12 Wawanesa


Figure 3.16.b: Slumping in the Souris Valley Below Wawanesa, 1981 photo

Figure 3.16.b: Slumping in the Souris Valley Below Wawanesa, 1981 photo

Vertical air photo: 8123 00-295

Flight height:  lens focal length:

Scale: 1:9,600 (approx.)

Date: 1981

Location: Township 7, Range 17 WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/12 Wawanesa


3.17: Rain Splash Erosion on Ground Moraine Near Minnedosa

The area is underlain by hummocky ground moraine on which there is no integrated drainage pattern. Many hollows are occupied by sloughs (small lakes) 1, although some of them have been infilled or drained 2. In some places the farmer has constructed drainage ditches to improve surface drainage and help in slough removal 3. Most of the area has been cleared for agriculture, but rings of vegetation—sedges, bulrushes, cattails, and dwarf willows—surround the sloughs4.[i] In this late summer photo some of the land is cropped 5, but some areas have been left fallow 6. On the fallow land rain splash has removed fine-grained and dark-coloured organic constituents of the soil from ridges, leaving behind light-toned coarse materials. The result is that even minor ridges of a few metres height stand out as light-toned areas 7. This effect is partially masked where the land is cropped but can still be observed 8.

The area displays the grid of the DLS system. Gravel roads follow section lines which can be easily seen 9, but quarter section lines are reflected by differences of land use and are not so easily identified 10. Six farms 11 exist in the area with most farm buildings being protected from the prevailing northwest winds by trees planted for this purpose 12. On this early morning image shadows are thrown almost due west 13.

Figure 3.17: Rain Splash Erosion on Ground Moraine Near Minnedosa

Figure 3.17: Rain Splash Erosion on Ground Moraine Near Minnedosa

Figure 3.17

Vertical air photograph: A18971-2

Flight height: 8,720 feet a.s.l.; lens focal length: 152.32 mm

Date: October 22, 1964

Scale: 1:17,000 (approx.)

Location: Township , Range

Map sheets: 1:250,000 62J Neepawa

1:50,000 62J/4 Moore Park

Notes

[i] Kiel, W. H. Jr., Hawkins, A. S. and Perret, N. G. Waterfowl habitat trends in the aspen parkland of Manitoba. Ottawa: Environment Canada, Canadian Wildlife Service, Report Series, Number 18, n. d.



3.18: Soil Erosion in the Little Saskatchewan River Valley

The Little Saskatchewan River occupies a large valley eroded into the ground moraine of the Minnedosa-Reston till plain.[i] Both the valley floor 1 close to the river and the valley sides 2 are covered by deciduous woodland, whereas much of the plain above the valley 3 has been cleared for agriculture. In some fields rain splash erosion has produced the characteristic light-toned hillcrests 4.

In this area, just below Minnedosa, the river meanders as it flows from northeast to southwest. Several abandoned meanders can be identified 5. Some are relatively new and still contain standing water 6, whereas others have been filled in and overgrown by trees 7. Other cutoffs are close to being created 8. Meander scars indicating previously higher river positions can be seen 9. South of the river a major river terrace has been preserved (between 10 and 11). Most of the terrace has been cleared for agriculture resulting in severe soil erosion. A series of southeast/northwest trending gullies can be seen 12, and sediment eroded from the top of the slope is deposited in fans lower down 13. Some of the fields have been left fallow, and (at 14) the farmer has started cultivating a field, either to deter soil erosion or to eliminate weeds. A north bank tributary enters the Little Saskatchewan depositing sediment near the junction of the two streams 15.

Settlement in the area is limited to two farms 16. Two railway lines cross the area 17, 18 and in the case of the more northerly line, a train can be seen on the line in the northwest corner of the photo 19. It is stationed close to an elevator that is identified by its distinctive shadow 20. A gravel road runs along the north valley side just above the floodplain 21, and other minor roads follow section lines of the DLS system.[ii] An east/west gravel road 22 is the northern boundary of township 14 that is a correction line in the system. The jog 23 is the extent of the correction at this location.

Figure 3.18: Soil Erosion in the Little Saskatchewan River Valley

Figure 3.18: Soil Erosion in the Little Saskatchewan River Valley

Figure 3.18

Vertical air photograph: A16065-32

Flight height: 9,500 feet a.s.l.; lens focal length: 152.08 mm

Date: June 10, 1958

Scale: 1:15,500 (approx.)

Location: Townships 14 and 15, Range 18 WI

Map sheets: 1: 250,000 62J Neepawa

1:50,000 62J/4 Moorepark

62J/5 Clanwilliam

Notes

[i] See Corkery, T. M. “Geology and Landforms of Manitoba” in J. Welsted, J. Everitt, and C. Stadel. eds. The Geography of Manitoba: Its Land and Its People. Winnipeg: The University of Manitoba Press, 1996. Figure 2.9, 21.

[ii] The road system in this area has changed considerably—associated with PTH 10 bypassing Minnedosa.


 


3.19: Soil Erosion on End Moraine Near Bruxelles

This area lies within the end moraine-covered Pembina Hills. The small Cypress River 1 flows from east to west in a mainly wooded valley 2. Most of the area has been cleared for agriculture although a few clumps of deciduous woodland have been left 3.

The agricultural land has been subjected to rain splash erosion producing the typical mottled appearance of bald crests and darker hollows 4. Numerous gullies radiate from an elevated area in the south 5, and severe soil erosion is evident at other locations 6.

The area is divided according to the squared DLS system, although the sections are not completely regular in shape perhaps due to errors in the original survey. Roads follow section lines 7, and some quarter sections can be identified on the basis of land use variations 8. PTH 34 9 traverses the area from north to south. The Cypress River has been straightened to improve drainage at the road crossing 10.

Ten farms are located in this area of about six square miles. Several of them show the standard arrangement of farm buildings surrounded by trees planted for shelter 11. Very dark fields have been left fallow 12. Crops at various stages of development cover lighter-toned fields 13. Cereal crops near harvesting stage probably cover very light-toned fields 14.

Figure 3.19: Soil Erosion on End Moraine Near Bruxelles

Figure 3.19: Soil Erosion on End Moraine Near Bruxelles

Figure 3.19

Vertical air photograph: A16185-153

Flight height: 10,500 feet a.s.l.; lens focal length: 152.63 mm

Date: July 22, 1958

Scale: 1:17,600 (approx.)

Location: Township 6, Ranges 10 and 11 WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/7 Somerset

 


3.20: Erosion and Deposition at the Foot of the Riding Mountain Escarpment

Cretaceous rocks, mainly shales overlain by glacial till, underlie the Riding Mountain Escarpment; the waters of Lake Agassiz that left behind numerous strandlines lapped the base of the escarpment. Many small streams descend the escarpment, dissecting it into steep-sided valleys and depositing the eroded shale in low-angle alluvial fans[i] at the base. Often the streams disappear into the fans before they can reach Lake Manitoba to the east.

In this area, southeast of Dauphin, the escarpment trends southeast/northwest, and the main creek is Crawford Creek 1 which is here incising itself into deposited shale 2 before disappearing into the ground near the northern edge of the photo 3. Another small, unnamed creek in 24/23/18WI[ii] has eroded shale and deposited it across a field cleared for agriculture 4. A similar but less marked effect can be seen in a field near the northern edge of the photo 5. This problem of shale deposition on to agricultural fields is common along the foot of the Riding Mountain escarpment. Poorly developed strandlines can be seen in the southeast 6 and northwest 7.

The area includes part of Riding Mountain National Park; the east/west and north/south cut line in the woodland 8 is the boundary of the park. Land in the park is covered by mixed deciduous/coniferous woodland 9 that extends north and east beyond the park boundary. Land in the east has been cleared for agriculture, and the section lines of the DLS system are obvious 10. A farm sheltered from northerly winds by planted trees can be seen near the northern edge of the photograph 11.

Figure 3.20: Erosion and Deposition at the Foot of the Riding Mountain Escarpment

Figure 3.20: Erosion and Deposition at the Foot of the Riding Mountain Escarpment

Figure 3.20

Vertical air photograph(s): A17717-107

Freight height: 9,420 a.s.l.; lens focal length: 152.15 mm

Date: July 12, 1962

Scale: 1:16,200 (approx.)

Location: Township 23, Ranges 17 and 18 WI

Map sheets: 1:250,000 62J Neepawa

1:125,000 MCR207 Riding Mountain National Park

1:50,000 62J/3 Neepawa

Notes

[i] McGinn, R.A. General Description of the Eastern Slopes of Riding Mountain. Brandon: Brandon University, unpublished manuscript, 1983.

[ii] Short for section 24, township 23, range 18 west of the principal meridian.


 

 


3.21: Gully Erosion on the Northern Flank of Turtle Mountain

In southern Manitoba surface run-off is quickly concentrated into specific channels that erode rills and gullies that over time are enlarged into stream valleys.

This photograph is of the northern fringe of Turtle Mountain, south of Deloraine. Turtle Mountain on the Canada/U.S.A. border is an upstanding area of Tertiary bedrock—the youngest bedrock in Manitoba—covered by glacial till. Its northern flank is inclined gently down to the north towards Whitewater Lake and the Souris River. In this area much of the former deciduous woodland has been cleared, although some patches 1 and strings along creek valleys 2 remain. Minor valleys (rills) 3 lead into gullies 4 and then into stream valleys 5. As is usually the case in southern Manitoba, rain splash erosion has produced light-toned hillcrests, particularly noticeable in fallow fields 6.

The area is subdivided according to the DLS system with gravel roads along some of the section lines 7. Three farms are visible 8, and at one, a dugout 9 has been created to improve water supply—certainly for animals and perhaps for human consumption—in this dry area of southwest Manitoba.

Figure 3.21: Gully Erosion on the Northern Flank of Turtle Mountain

Figure 3.21: Gully Erosion on the Northern Flank of Turtle Mountain

Figure 3.21

Vertical air photograph: A19904-147

Flight height: 9700 feet a.s.l.; lens focal length: 152.16 mm

Date: May 28, 1967

Scale: 1:15,500 (approx.)

Location: Township 2, Range 23 WI

Map sheets: 1:250,000 62F Virden

1:50,000 62F/2 Waskada


3.22: Rain Splash, Rill and Gully Erosion South of the Assiniboine River, South of Lavenham

The eastward flowing Assiniboine River 1 clips the northern edge of the photo. In this area the Assiniboine River is etched into the Assiniboine Delta that is composed of sands. The meandering river shows the characteristic river cliff 2 on the outside of the bend with a grass and willow covered point bar 3 on the inside of the bend. Most of the land has been cleared for agriculture with the exception of a block of deciduous woodland in the north 4 and strips of woodland along creek channels 5. The cleared land displays the mottled tones 6 characteristic of sandy soils. Rain splash erosion results in light tones on slightly elevated areas 7. In other areas erosion is concentrated along minor rills 8. Some of these 9 lead towards a larger gully 10 that combines with another gully from the south 11 before reaching the Assiniboine. Water from these gullies has deposited a small delta 12 into the Assiniboine. Rather surprisingly the gullies are most obvious where they cut across wooded land 13. In two cases gullies are retreating from wooded areas into agricultural land by a process of headward erosion with a steep head wall 14 at the point of maximum extent.

Figure 3.22: Rain Splash, Rill and Gully Erosion South of the Assiniboine River, South of Lavenham

Figure 3.22: Rain Splash, Rill and Gully Erosion South of the Assiniboine River, South of Lavenham

Figure 3.22

Vertical air photograph: A16621-79

Flight height: 9000 feet a.s.l.; lens focal length: 6 inches

Scale 1:16,200 (approx.)

Date: July 18, 1959

Location: Township 9; Range 10WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/10 Treherne


3.23: Dissection of a Till Plain Near Foxwarren

In geological terms much of the land surface of southern Manitoba is very new, dating from the retreat of the last ice sheet no more that about 10,000 years ago. In the area shown, river channels are etching valleys in a till plain deposited during the Wisconsinan ice age. Snake Creek, a tributary of the Assiniboine—just off the photograph to the southwest—has already created a deep well-defined valley 1 wandering through the western side of this area. The steep-sided, flat-floored nature of the valley in the north 2 suggests that it used to carry much more water. Small creeks, tributary to Snake Creek, are gradually dissecting the till plain by headward erosion 3, and in at least two places, 4 small dams have been built either to prevent erosion or to catch water for agricultural use, or both. Several dark-toned lakes and sloughs have not been integrated into the drainage system 5. Much of the land in the south and west is still covered by deciduous forest, but in the north and east more land has been cleared for agriculture. Because of the irregular topography, fields are smaller than is often the case in southwestern Manitoba. The land is subdivided according to the DLS system, but roads do not follow all section lines, and the direction of some roads is clearly topographically determined 6. The CPR 7 line connects Birtle, just off the photo to the south and Foxwarren 8 in the north. As is commonly the case in small Manitoba settlements, the roads in the latter are parallel and at right angles to the railway line.

Figure 3.23: Dissection of a Till Plain Near Foxwarren

Figure 3.23: Dissection of a Till Plain Near Foxwarren

Figure 3.23

Vertical air photograph: A15530-50

Flight height: 20,000 feet a.s.l.; lens focal length: 152.26 mm

Date: October 9, 1956

Scale: 1:36,800 (approx.)

Location: Townships 17 and 18, Range 27 WI

Map sheets: 1:250,000 62K Riding Mountain

1:50,000 62K/6 Birtle


3.24: Meanders and Cutoffs on the Assiniboine River South of St. Lazare

The Assiniboine River occupies a glacial spillway, the floor of which ranges in width from about 1300 yards (1189 m) in the centre of the photo to 1700 yards (1554 m) in the north and south. Conditions are ideal for meander development; the river has a low gradient and the channel is cut into unconsolidated, but cohesive, surficial materials. The cohesiveness allows river cliffs to develop where the river erodes the outside of meander bends.

The modern river channel tends towards the western side of the spillway with clearly defined cutoffs east of the main channel at four locations 1. Two more cutoffs are imminent 2. In the south, a stretch of river rather than an individual loop has been abandoned 3. The main channel of the river 4 is light-toned because of reflection from suspended sediment in the water, whereas the cutoffs are dark-toned because there is no water movement to suspend sediments. Classic meander scrolls 5 indicate former positions of the riverbank. Trees (often willows) occupy the ridges of the scrolls whereas the intervening swales are marshy.

The spillway is incised into flat land to west and east 6 (Wattsview Plains). The western valley side is the more clearly defined of the two. Most of it is wooded, but some bare land exists where spring-fed gullies occur 7. The eastern side is less uniformly wooded; some parts are grass covered 8 because of the dry microclimate on the west and southwest facing slopes. A series of minor gullies exist 9, and in the north is the wooded valley of Snake Creek 10. Several small lakes can be seen 11.

Most of the eastern plain is used for agriculture, and, as is usual on hummocky ground, rain splash has resulted in light-toned areas at the tops of mounds 12. In contrast the plain west of the spillway is wooded or grass covered 13. Sandy outwash deposits underlie most of the area, and some of the sand has been blown into linear dunes aligned roughly northwest/southeast 14. Some ridges are devoid of vegetation where wind erosion has exposed the underlying sands 15.

Section lines of the DLS system can be seen in the east with a few gravel roads 16. These roads are straight, but within the spillway road direction is influenced by the topography 17. The CN line connecting St. Lazare (off the photo to the north) with Birtle (off the photo to the south) runs just above the level of the floodplain 18; slumping has disrupted the line and partially in filled a cutoff 19. The Assiniboine River and its valley in this area is a major impediment to east-west communications; there is no river crossing by road or railway line for at least 25 miles (40 km) south from St. Lazare.

Figure 3.24: Meanders and Cutoffs on the Assiniboine River South of St. Lazare

Figure 3.24: Meanders and Cutoffs on the Assiniboine River South of St. Lazare

Figure 3.24

Air photograph: A15528-148

Flight height: 20,000 feet a.s.l.; lens focal length: 152.26 mm

Date: May 27, 1956

Scale: 1:36,200 (approx.)

Location: Township 16, Ranges 27 and 28 WI

Map sheets: 1:250,000 62K Riding Mountain

1:50,000 62K/6 Birtle

 


3.25: The Assiniboine Glacial Spillway: Meanders and Abandoned River Segments

Here the Assiniboine spillway floor varies from under one mile (1.5 km) to over two miles (3.2 km) in width. The main river channel hugs first the southwest bank of the spillway 1, then the northeast 2, before transferring back the west bank 3. Two small abandoned meanders can be seen 4, but more obvious are long segments of the river that have been left behind by the migrating river 5.

The Assiniboine wanders across the spillway floor in a series of irregular meanders, leaving behind clearly defined meander scrolls 6. Part of the floodplain in the northwest has been reclaimed for agriculture and is protected from flooding by the main river channel by an embankment (dike) 7. Even so some of the land, the site of the old river channel, is too wet for agriculture 8.

The south and west bank of the spillway is steep, well-wooded and broken by only one minor gully in the south 9, whereas the north and east bank is less steep, not so uniformly wooded because of the dry microclimate on southwest and west facing slopes, as well as being broken by four major gullies 10 and many minor ones.

Flat land exists on either side of the spillway. In the west glaciofluvial materials pulled into northwest/southeast trending ridges underlie the surface 11. Linear sloughs occupy depressions 12, and the surface is covered by scrubland with patches of trees 13. East of the spillway much of the land is used for agriculture. Light-toned hillcrests can be seen in fallow fields 14. Roads follow the section lines of the DLS on flat land but are influenced by the topography on the spillway sides 15.

Figure 3.25: The Assiniboine Glacial Spillway: Meanders and Abandoned River Segments

Figure 3.25: The Assiniboine Glacial Spillway: Meanders and Abandoned River Segments

Figure 3.25

Vertical air photograph: A15527-134

Flight height: 20,000 feet a.s.l.; lens focal length: 152.26 mm

Date: October 7, 1956

Scale: 1:37,300 (approx.)

Location: Township 12 and 13, Ranges 25 and 26 WI

Map sheets: 1:250,000 62K Riding Mountain

1:50,000 62K/2 Hamiota


3.26: Glacial Spillway and the Meandering Assiniboine River North of Virden

The Assiniboine River occupies a steep-sided, flat-floored glacial spillway about one to one and a half miles (1.6 to 2.4 km) across at its base. Cutoffs can be seen at several locations 1, and a segment of the river has also been abandoned 2. Another small cutoff is imminent 3. The two most clearly defined cutoffs 4 were in existence when the original DLS maps were made in 1873. Neither now receives water from the main river channel, but in both cases when they contain a lot of water it flows out from them to the river. In both cases enough time has elapsed since abandonment for trees to grow across the meander neck 5.

Both sides of the spillway are wooded, and steep-sided mainly wooded gullies dissect both the west bank 6 and east bank 7. Woodland (dark-toned) can also be seen skirting the river channel 8, but further back on the floodplain land has been cleared for agriculture 9.

On either side of the spillway land is flat. On the west side there are extensive areas of scrubland with tree clumps 10 developed on sandy outwash deposits. Further west and also east of the spillway, land is devoted to agriculture 11. Light-toned hummocks can be seen in many of the fields 12.

The section lines of the DLS system are obvious with north/south 13 and east/west 14 gravel roads along some of them, although in some locations the road direction is influenced by the topography 15. One road runs obliquely down the valley side and then along the spillway just above the floodplain 16. The CP line, totally unrelated to the survey system, can be seen at the western edge of the photo 17.

Figure 3.26: Glacial Spillway and the Meandering Assiniboine River North of Virden

Figure 3.26: Glacial Spillway and the Meandering Assiniboine River North of Virden

Figure 3.26

Vertical air photograph: A24966-242

Flight height: 15,433 feet a.s.l.; lens focal length: 85.32 mm

Date: June 18, 1978

Scale: 1:52,800 (approx.)

Location: Township 12, Range 25 WI

Map sheets: 1:250,000 62F Virden

1:50,000 62F/15 Virden

62K/2 Hamiota


3.27: The Assiniboine Spillway, Assiniboine River, and a Cutoff

This low oblique photo, so called because no horizon is showing, is of one of the cutoffs 4 on the vertical air photo of Figure 3.26. The view is from the east, looking west across the Assiniboine spillway. This photo is unusual in that it was taken in winter when there was a thin snow cover that enhances the topographic details.

The wooded west wall of the spillway is seen in the foreground 1. The spillway runs across the photo with the river channel on the valley floor 2. The cutoff is in the centre 3, and another one is imminent 4. Meander scrolls emphasized by the woodland and snow cover are evident within the meander loop 5. The east side of the spillway is in the background, dissected by two steep-sided wooded gullies 6.

Figure 3.27: The Assiniboine Spillway, Assiniboine River, and a Cutoff

Figure 3.27: The Assiniboine Spillway, Assiniboine River, and a Cutoff

Figure 3.27

Low oblique air photo

Date: December 6, 1965

Scale: Variable-- larger in foreground, smaller in background.

Location: Township 12, Range 25 WI

Map sheets: 1:250,000 62F Virden

1:50,000 62F/15 Virden


3.28: The Assiniboine Spillway, Assiniboine River, and an Abandoned Channel

This low oblique photo was taken looking along the Assiniboine spillway from south to north. An old abandoned channel (the southern most 4 in Figure 3.26) can be seen in the centre 1. The snow cover emphasizes the meander scrolls within the abandoned loop 2. In other areas, the trees that tend to grow on the ridges 3 pick out meander scrolls. A road runs along the east side of the spillway, just above the floodplain 4.

Figure 3.28: The Assiniboine Spillway, Assiniboine River, and an Abandoned Channel

Figure 3.28: The Assiniboine Spillway, Assiniboine River, and an Abandoned Channel

Figure 3.28

Low oblique air photo

Date: December 6, 1965

Scale: Variable--larger in foreground, smaller in background

Location: Section 31, Township 11, Range 25 WI (location of cutoff)

Map sheets: 1:250,000 62F Virden

1:50,000 62F/15 Virden

 


3.29: Meanders on the Assiniboine River North of Glenboro

East of Brandon the Assiniboine River is incised into the deposits of the Assiniboine Delta. In the area shown the river has cut down through the deltaic sands into the underlying clay. The gentle long profile of the river and the fact that it is eroding into uniformly resistant clay provide ideal conditions for meander development. The clay is easily eroded but is sufficiently cohesive to stand up in steep banks.

The photo shows that the river erodes into the concave side of meanders producing low, steep river cliffs 1 and leaves deposits on the convex side to produce sandy point bans 2. As the river migrates laterally, it leaves behind meander scrolls indicating its former positions 3. Point bans are at first bare but are later covered by grass 4 and then trees 5. The scrolls are visible in fields devoted to agriculture 6 and where trees have been left on ridges 7.

In the east sand dunes can be seen 8. These are mainly stabilized by grasses and trees but some bare sand patches remain 9.

On the outside of one large bend, sapping caused by springs at the junction between the surface sands and the underlying clay has resulted in a series of amphitheatre-like embankments 10, and just to the north where the river is eroding into dunes, a high cliff has been produced 11.

The trees in this area are mainly deciduous, and in this fall photograph some have changed colour producing a light tone 12, while others, as indicated by their shadows, have completely lost their leaves 13. In one area coniferous trees, probably white spruce (Picea glauca),[i] predominate 14. There are also isolated patches of, and individual, coniferous trees scattered throughout the area. These are identified from their distinctive triangular-shaped shadows 15.

Some of the land is devoted to arable agriculture; three farms can be identified 16. Within the northeastern meander loop an intricate pattern 17 is caused by trails along which straw bales have been assembled in stacks 18. A north/south gravel road 19 along one of the section lines skirts around a meander in the north and leads to a now abandoned ferry 20.

Figure 3.29: Meanders on the Assiniboine River North of Glenboro

Figure 3.29: Meanders on the Assiniboine River North of Glenboro

Figure 3.29

Vertical air photograph: A16405-13

Flight height: 10,500 feet a.s.l.; lens focal length: 152.63 mm

Date: October 19, 1958

Scale: 1:18:100 (approx.)

Location: Township 8, Ranges 13 and 14 WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/11 Glenboro

Notes

[i] Kerr, G. D., Rounds, R. C., and Welsted J. “Use of panchromatic and colour infrared air photographs to produce a vegetation map for Canadian Forces Base Shilo, Manitoba”in 5th Canadian Symposium on Remote Sensing, Proceedings. Victoria B.C., 1978, 408-412.


 


3.30: The Assiniboine River in Spruce Woods Provincial Park

As in Figure 3.29 the Assiniboine River has cut through sands into clays to produce optimum conditions for meandering. In this photo the river wanders from west to east through the sand hills of Spruce Woods Provincial Park. Also as in Figure 3.29 river cliffs are found on the outside of river bends 1 and sandy point bars on the inside 2. Meander scrolls are obvious both in wooded areas 3 and where land has been cleared for agriculture 4. Numerous cutoffs of various ages can be seen. An indistinct one 5 is probably the oldest; it is well removed from the river and is completely infilled. Several still contain some water 6 and are probably newer although they were already in existence when the original DLS map was compiled in 1909. Another cutoff 7 is much more recent; it was part of the main river channel in 1909. Now (1951) it is completely cut off and sediment has been deposited across the meander neck 8.

In the southeast a combination of spring sapping and slumping has produced a series of embayments 9, and both north and south of the river are water-eroded dry ravines 10. Stabilized sand dunes exist on both sides of the river, with one small patch of open sand 11.

Spruce Woods Provincial Park is unique in that “three major North American vegetation formations overlap: the grassland (or “prairie”), the boreal (northern coniferous) forest and the temperate (eastern deciduous) forest.”[i] On the photograph grassland 12; coniferous trees, probably white spruce (Picea glauca) identified by their dark tone and triangular shadow 13; and deciduous trees 14 are all visible. Yellow and light-brown leaves on the deciduous trees—mainly aspen (Populus tremuloides)—give some a light tone on this fall photograph.

A small area mainly on the floodplain has been cleared for agriculture 15. Only a few farm trails penetrate the area 16.

Figure 3.30: The Assiniboine River in Spruce Woods Provincial Park

Figure 3.30: The Assiniboine River in Spruce Woods Provincial Park

Figure 3.30

Vertical air photograph: 15577-20

Flight height: 20,000 feet a.s.l.; lens focal length: 153.09 mm

Date: October 11, 1956

Scale: 1:37,900 (approx.)

Location: Townships 8 and 9, Ranges 12 and 13 WI

Map sheets: 1:250,000 62G Brandon 

1:50,000 62G/11 Glenboro

Notes

[i] Rogosin, A. “The Spruce Woods Sandhills” in Wested, Everitt, and Stadel, op. cit. 1996, 56-59.


 

 


3.31: Detail of a Cutoff on the Assiniboine River

This low level photograph was taken 30 years after that in Figure 3.30. It shows the cutoff in figure 3.30 in detail as well as revealing changes that have occurred over the intervening years. The main channel of the Assiniboine is seen in the southwest 1, southeast 2, and northeast 3, and the cutoff occupies the central part of the photo.

The cutoff has been unfilled by sediment and vegetation 4 but some standing water remains 5. The neck of the abandoned channel that was bare sand in 1951 is now (1981) covered by vegetation, including some trees, probably willows (Salix spp) 6. Both within the cutoff 7 and to the west of it 8, meander scrolls can be seen with trees occupying the ridges and grass the swales in between.

The photograph was taken in the spring before the leaf-on stage for some trees as revealed by their shadows 9, but other with round crowns seem to have some foliage 10.

Figure 3.31: Detail of a Cutoff on the Assiniboine River

Figure 3.31: Detail of a Cutoff on the Assiniboine River

Figure 3.31

Vertical air photograph: 8103 00 098

Flight height:   lens focal length:

Date: May 5, 1981

Scale: 1:5,000 (approx.)

Location: Section 25, Township 8, Range 13 WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/11 Glenboro


3.32: Deltas in Red Deer Lake

Red Deer Lake occupies a basin scoured into Devonian sediments north of the Porcupine Hills (part of the Manitoba Escarpment). This photo shows part of the southwest shore of the lake. Red Deer River 1, which flows between wooded levees (natural embankments) 2, enters the lake from the northwest and has deposited a “birds foot” type of delta 3 characteristic of water bodies without significant tidal fluctuation. The river splits into two distributaries 4, both of which deposit sediment where they enter the lake resulting in dark-toned areas 5. On a smaller scale, Armit River 7 has deposited a similar delta 8, and further south Camp Seven Creek 9 has created another coastal projection 10. The sub-parallel lines 11 represent former higher lake levels.

Most of Red Deer Lake is light-toned but dark areas appear where rivers enter and deposit sediment 5 and 12, and sediment swirls are clearly seen in the north 13.

Figure 3.32: Deltas in Red Deer Lake

Figure 3.32: Deltas in Red Deer Lake

Figure 3.32

Vertical air photograph: A15973-116

Flight height: 20,000 feet a.s.l.; lens focal length: 152.17 mm

Date: May 14, 1958

Scale: 1:40,000 (approx.)

Location: Townships 45 and 46, Ranges 28 and 29 WI

Map sheets: 1:250,000 63C Swan Lake

1:50,000 63C/14 Barrows


3.33: Part of the Saskatchewan River/Summerberry River Delta Northwest of Cedar Lake

The photograph shows two main river channels, Summerberry River to the north 1 and the Saskatchewan River to the south 2, that flow eastward into Cedar Lake, as well as several other distributary channels. Between the two main channels is dark-toned Kakeenoskak Island 3 which is probably fen covered. “Periodically the region floods, at which time water in the delta distributary channels over flows the banks and spills across the levees.” It is here that crevasse splay deposits have formed. 4 In this extensive wetland, wooded natural levees 5 and scroll bars 6 show up much darker than the marshes that are fairly uniform and light in tone 7. “Typically, sedges, coarse grasses, reeds and rushes flourish in the marshes and account for the lighter tones.” Floating fen is seen where the water depth is very shallow and the level fluctuates throughout the summer 8. Criss-crossing linear features 9 are “ice gouge markings” made by the keels of wind or current-driven icebergs on the floor of glacial Lake Agassiz.[i]

The main river channels are uniformly light-toned resulting from suspended sediment, whereas lakes are variable ranging from almost black 10, to dark grey-Seepeesis Lake 11, to light grey--Kapakwak Lake 12 that is probably shallow enough that winds stir up bottom sediments.

Figure 3.33: Part of the Saskatchewan River/Summerberry River Delta Northwest of Cedar Lake

Figure 3.33: Part of the Saskatchewan River/Summerberry River Delta Northwest of Cedar Lake

Figure 3.33

Vertical air photograph: A13860-8

Flight height: 35,000 feet a.s.l.; lens focal length: 154.15 mm

Date: September 23, 1953

Scale: 1:19,000 (approx.)

Location: Townships 53 and 54, Ranges 23 and 24 WI

Map sheets: 1:250,000 63F The Pas

1:50,000 63F/10 Red Earth Lake

Notes

[i] Interpretation from Mollard and Janes, op. cit. 1984, 135.


 

 


3.34: Part of the Saskatchewan River Delta in Cedar Lake

This complex of river channels, lakes, and marshes is part of the Saskatchewan River delta where the river enters Cedar Lake from the northwest. The main channel of the Saskatchewan River 1 runs southeast through the centre of the photograph; numerous distributaries branch off from it including two that are named Baptising Creek 2 and McKenzie Creek 3. The photograph illustrates the usefulness of air-photos as historical records; it was taken in 1953 when the area was in its natural state, long before the construction of the Grand Rapids dam near where the Saskatchewan River flows into Lake Winnipeg. The dam raised the water level in Cedar Lake so that recent maps of the area show much of the 1953 marshy land covered by water.

The main water channels, heavily laden with sediment, are light-toned 4, whereas lakes are mainly dark-toned 5 except where the water is shallow 6. Dark-toned wooded levees 7 follow the main channel. Marshy areas are light-toned 8, but there are some dark-toned areas of floating fen 9. The circular darker-toned areas 10 in the light-toned lake—the northwest part of Cedar Lake—are probably patches of aquatic vegetation.

Figure 3.34: Part of the Saskatchewan River Delta in Cedar Lake

Figure 3.34: Part of the Saskatchewan River Delta in Cedar Lake

Figure 3.34

Vertical air photograph: A13935-96

Flight height: 35,000 feet a.s.l.; lens focal length: 6 inches

Date: October 28, 1953

Scale: 1:68,320 (approx.)

Location: Townships 52 and 53, Ranges 22 and 23 WI

Map sheets: 1:250,000 63F The Pas

1:50,000 63F/10 Red Earth Lake


3.35: Deltas in Swan Lake

Swan River 1 and Woody River 2 drain the land between the Porcupine Hills 3 and Duck Mountain, off the image to the south. Both have deposited sediment into the west side of Swan Lake 4 to create deltas. That deposited by Woody River and Birch River—too small to be visible on this high-level image—is simple in form with just one main projection 5. The delta of Swan River and its distributary Rat Creek 6 is more complex, resembling the classic bird’s foot type of delta 7. Within the deltaic area are a number of small lakes, the most obvious of which is Plum Lake 8. East of Swan Lake is Pelican Lake 9. The two large lakes—Swan Lake and Pelican Lake—are very different in colour; Swan Lake, with a high suspended sediment concentration, is milky blue, whereas Pelican Lake, sediment free, is dark blue. The latter receives only small tributaries from relatively flat land, whereas Swan Lake receives Woody River and Swan River whose tributaries flow from the Porcupine Hills and Duck Mountain

Figure 3.35: Deltas in Swan Lake

Figure 3.35: Deltas in Swan Lake

Figure 3.35

Google Image

Scale: 1:361,000 (approx.)

Date: Taken from Internet August 2006

Location: North end of Swan River Delta: 52º 30' N; 100º 45' W

Map sheets: 1:250,000 63C Swan Lake


3.36: Swan River Delta

This large-scale air photo shows detail of the Swan River Delta. Swan River 1 flows northeast into Swan Lake 2 and along with its distributary, Rat Creek 3, has deposited a bird’s foot type of delta. Wooded levees 4 follow the course of Swan River. Back from the levees are marshy areas 5 and lakes 6 with some higher, wooded areas 7. Sediment swirls are clearly seen in the lake 8.

Figure 3.36: Swan River Delta

Figure 3.36: Swan River Delta

Figure 3.36

Vertical air photograph: A15607-105

Flight height: 19,800 feet a.s.l.; lens focal length: 152.14 mm

Scale: 1:38,500 (approx.)

Date: June 1, 1957

Location: Township 40; Ranges 23 and 24W1

Map sheets: 1:250,000 63C Swan Lake

1:50,000 63C/7 Lenswood


3.37: Part of the Red River Delta at the South End of Lake Winnipeg

This photograph is less complex than Figure 3.34, but the essential elements are the same. One of the north flowing Red’s distributaries, Salamonia channel, can be seen at the centre 1. It is joined by another distributary 2 that splits from the main channel of the Red, off the image to the east. In the north another distributary can be seen 3, and in the south another one 4 spills into Cochrane Lake 5. East of the large central channel are Passwa Lake 6 and Hughes Lake 7. The sediment-laden, light-toned channels run between levees 8, separating them from the lakes. The light tone of the levees suggests that they are not wooded, probably because of major fluctuations in water level along the channel sides. Several spillovers can be seen 9 as can a small area of marshy land 10.

Figure 3.37: Part of the Red River Delta at the South End of Lake Winnipeg

Figure 3.37: Part of the Red River Delta at the South End of Lake Winnipeg

Figure 3.37

Vertical air photograph: A9710-82

Flight height: 12,270 feet a.s.l.; lens focal length: 8.24 inches

Date: May 7, 1946

Scale: 1:16,800 (approx.)

Location: Township 16, Range 5 WI

Map sheets: 1:250,000 62 I Selkirk

1:50,000 62I/7 Netley Marsh


3.38: Shell River Valley North of Roblin

Several of the streams flowing from the west side of Riding Mountain and Duck Mountain flow in valleys which are too large for their present discharge; in technical terms, they are misfit streams. The discrepancy between valley size and stream size is explained by the fact that the two highland areas supported ice caps that melted rapidly at the end of the ice age. This produced huge quantities of water that eroded large valleys, possibly in a very short time. Once the ice had melted and the volume decreased, the river channels reverted to their present form.

The photograph shows the Shell River 1 (and valley) 2 that flows southward from the southwest side of Duck Mountain. At the time of maximum ice melt, the channel occupied the area bounded by dashed lines. As the channel was etched into ground moraine—still preserved to east and west—it was free to migrate laterally, and as with all meandering channels, it migrated in the direction of the concave bank as indicated by arrows 3 and left behind scroll bars indicating its former position 4. The banks of the older channel, across which it migrates from one side to another, confine the present channel.

Some of the land has been cleared for agriculture, and as was the practice at the time, much of it has been left fallow. In these fields the dark chernozemic soils produce a very dark tone on the photo 5. The only major transport route in the area is PTH 83 6 leading southwards to Roblin 5 miles south of the photo.

Figure 3.38: Shell River Valley North of Roblin

Figure 3.38: Shell River Valley North of Roblin

Figure 3.38

Vertical Air Photograph: A21085-218

Flight height: 21,500 feet a.s.l.; lens focal length: 152.52 mm

Date: July 17, 1969

Scale: 1:38,400 (approx.)

Location: Townships 26 and 27, Ranges 27 and 28 WI

Map sheets: 1:250,000 62 N Duck Mountain

1:50,000 62 N/6 Burrows Lake


3.39: The Little Saskatchewan River Valley Northeast of Newdale

The Little Saskatchewan River 1 flows south from Riding Mountain, and at the location shown occupies a meander belt about 1500 feet (457 m) across 2. In the past, when ice over Riding Mountain was melting rapidly, the river channel occupied the whole of the present meander belt and was confined within a valley whose position is indicated by the dashed lines 3. The wide river channel migrated in the direction indicated by the arrows 4 leaving behind flat land, most of which has been cleared for agriculture. The present meandering channel has abandoned several meanders 5.

This is a spring photo, and patches of snow can still be seen in the valley 6. Also at this time of rapid snow melt, parts of the floodplain are inundated resulting in a dark tone 7. Three gullies enter the main valley from the north; one is clearly occupied by a stream 8, but the others 9 appear dry. Similar dry gullies enter from the south 10. Outside the valley the surface is underlain by ground moraine with numerous hollows that in the spring are lake filled; however, the topographic map of the area shows many of these lakes as intermittent 11.

The land is divided according to the DLS system with roads following north/south and east/west section lines even across some lakes 12. However, in some places the topography determines road direction as, for example, down the valley side 13 and along the valley side 14. The east/west road 15 is, judging by its light tone, newly constructed.

Figure 3.39: The Little Saskatchewan River Valley Northeast of Newdale

Figure 3.39: The Little Saskatchewan River Valley Northeast of Newdale

Figure 3.39

Vertical air photograph: A15225-27

Flight height: 20,000 feet a.s.l.; lens focal length: 152.26 mm

Date: May 24, 1956

Scale: 1:35,200 (approx.)

Townships 16 and 17, Ranges 19 and 20 WI

Map sheets: 1:250,000 62K Riding Mountain

1:50,000 62K/8 Newdale


3.40: Upper Limestone Rapids on the Nelson River

The photograph shows the Upper Limestone Rapids on the Nelson River about 80 kilometres southwest of Hudson Bay. “The Nelson has a steep gradient with numerous rapids, high water flows and high ice production.”[i] Here the river 1, which is about 0.5 miles (0.8 km) across at the southern edge of the photo and about 0.8 miles (1.3 km) across at the eastern edge, flows through three sets of rapids 2 with the upper one being at about 200 feet (61 m) above seal level. The Nelson is joined by the Limestone River 3 from the west and by Moondance Creek 4 from the south. The dark-toned Limestone River contrasts with the light-toned sediment-laden Nelson. The flow of the Limestone is deflected along the north bank of the Nelson 5 before eventually merging with the flow of the larger river. A well-defined terrace 6 can be seen on the north side of the Limestone. Most of the area is covered by a thin till layer on which muskeg has developed 7, but some dark-toned coniferous trees grow near the main river channel 8.

At the time the photo was taken the only evidence of human activity is the Hudson Bay Railway line 9 that leads north to Churchill. Two spurs lead into gravel pits 10. However, the Limestone power station has since been constructed 11 and the settlement of Sundance, built to house the workers involved in the building of the dam, was constructed 12.

Figure 3.40: Upper Limestone Rapids on the Nelson River

Figure 3.40: Upper Limestone Rapids on the Nelson River

Figure 3.40

Vertical air photograph: A14126-37

Flight height: 31,000 feet a.s.l.; lens focal length: 153.19 mm

Date: July 1, 1954

Scale: 1:61,600 (approx.)

Location: Townships 86 and 87; Ranges 21 and 22 E

Map sheets: 1:250,000 54 D Kettle Rapids

1:50,000 54D/9 Amery

Notes

[i] Mollard and Janes, op. cit. 1984, 91.


 


3.41: River Capture on the Souris River South of Wawanesa

In immediate post-glacial time, a river flowed along the southern edge of the Tiger Hills (part of the Darlingford end moraine) occupying a spillway that now contains the Souris River, Langs Valley, Pelican Lake and Lorne Lake. The spillway used to carry water from glacial lakes, Souris and Hind, in the west to glacial Lake Agassiz in the east. At that time the proto-Souris, a tributary to the Assiniboine, was extending itself southwestward by headward erosion into, and eventually through, the Tiger Hills, possibly occupying an old glacial melt water channel through the hills. Eventually the proto-Souris met up with and captured the flow of the river in the spillway.

Today the Souris 1 takes a sharp bend at the elbow 2 and then flows through the Tiger Hills 3 in a steep-sided gorge. A small, unnamed stream 4 flows westward against the original flow to join the Souris at the elbow. Above the elbow, the Souris has incised a steep-sided inner valley into the floor of the spillway, the sides of which can be seen to the north 5 and south 6. On the north side a terrace 7 represents a former water level in the spillway. The south side is broken by two small gullies 8.

Since capture, the Souris has eroded rapidly through the end moraine of the Tiger Hills into the underlying shale that can be seen at a sharp bend in the river 9. Slumping has occurred on the west side of the valley 10. The river’s speed of the flow is fast for a prairie river and shallow rapids can be seen on this summer image 11. The south bank (north-facing) is heavily wooded but the north side—south facing and therefore drier—is covered by a mixture of grasses and trees, the latter in evidence in wetter “draws” 12. Both sides of the gorge through the Tiger Hills are thickly wooded, but the hills themselves have patchy woodland surrounded by grass.

A gravel road, PR 346 13, runs north/south across the area with a rare—for southern Manitoba—hairpin bend 14 on the south side of the spillway.

Figure 3.41: River Capture on the Souris River South of Wawanesa

Figure 3.41: River Capture on the Souris River South of Wawanesa

Figure 3.41

Vertical air photograph: A11048-244

Flight height: 9,520 feet a.s.l.; lens focal length: 6 inches

Date: May 31, 1947

Scale: 1:15,840 (approx.)

Location: Township 6; Range 18 WI

Map sheets: 1:250,000 62 G Brandon 

1:50,000 62G/5 Dunrea


3.42: Incised Meanders on the Souris River Near Wawanesa

Below the Souris elbow of capture (Figure 3.41), the Souris River cuts through the Tiger Hills and then across a flat area underlain by lacustrine sediments. Here the Souris has incised its channel through the lacustrine sediments and glacial till and into the underlying shale bedrock. The incision is probably associated with the river capture that was responsible for the elbow of capture. After capture occurred the river was not only flowing to a lower local base level—the Assiniboine just off the photo to the north—it also had an increased volume.

In the photo the incised meanders have eroded steep cliffs on the concave side 1 and have left behind gentle slip-off slopes on the convex side 2. North of Wawanesa one incised meander has been abandoned 3, and the river has since cut down between 25 feet (7.6 m) and 50 feet (15.2 m). Smaller bends on the river superimposed on to the meanders are typified by sand deposition—light-toned—on the inside 4. The Tiger Hills in the south are formed of hummocky end moraine with many small lakes in depressions 5. In the southwest the hills are still wooded (dark-toned), but in the southeast they have been cleared for agriculture. The steep sides of the Souris Valley are wooded 6, but the flat land to the north and south is excellent farmland.

The land is subdivided according to the DLS system. This area lies in townships 6 and 7; a correction line occurs along the north edge of township 6 7. The village of Wawanesa 8 lies within one of the Souris meanders and was, when the photo was taken, the focus of transport routes in the area. The CN railway line 9, long ago abandoned, passes through the village; PTH 2 10 runs east/west; PR 340 enters the village from the north 11; and PTH 18 runs southwards 12. A light-toned line can be seen in some fields 13; the light tone results from the disturbance of soil and surficial rocks when a pipeline was laid.

Figure 3.42: Incised Meanders on the Souris River Near Wawanesa

Figure 3.42: Incised Meanders on the Souris River Near Wawanesa

Figure 3.42

Air photograph: A24519-231

Flight height: 26,200 feet a.s.l.; lens focal length: 6 inches

Date: August 1, 1976

Scale: 1:48,800 (approx.)

Location: Townships 6 and 7; Ranges 16 and 17 WI

Map sheets: 1:250,000 62G Brandon 

1:50,000 62G/12 Wawanesa


3.43: Spring Sapping Along the Banks of the Assiniboine River in Canadian Forces Base (CFB) Shilo

In this area, below Brandon, the Assiniboine River 1 has incised itself into the sands and clays of the Assiniboine Delta. The light tone of the river, caused by reflection from suspended sediment, contrasts with the dark tone of a cutoff with no suspended sediment 2. Spring sapping, where ground water comes to the surface at the junction of permeable sands above with impermeable clay below, has resulted in the retreat of the river’s north bank producing a scalloped edge 3 with occasional deeper embayments 4. On the river’s south side, scroll bars 5—some emphasized by trees 6—can be seen. Trees in the river valley are mainly deciduous with occasional patches of coniferous trees—mainly white spruce (Picea glauca)—identified by their dark tone 7 and conical shadow shape 8.

North of the river is a light-toned, grass-covered plain 9 with scattered dark-toned patches 10; these are clumps of creeping juniper (Juniperus horizontalis), a species that grows well on the thin sandy soil. Further north are stabilized sand dunes 11 with some poorly defined longitudinal dunes 12 that support dark-toned coniferous trees, mainly white spruce (Picea glauca). Other areas are covered by light-toned grasses 13 and medium-toned woodland 14, mainly trembling aspen (Populus tremuloides).[i]

Within the river bend land is used for agriculture, and a large gravel pit exists 15 that exploits gravel and sand left behind in scroll bars as the river migrated northwards. Land north of the river is part of Canadian Forces Base (CFB) Shilo and is used for military training. Two sand/gravel roads exist 16 as well as many light-toned paths 17 used to transport vehicles during military exercises.

Figure 3.43: Spring Sapping Along the Banks of the Assiniboine River in Canadian Forces Base (CFB) Shilo

Figure 3.43: Spring Sapping Along the Banks of the Assiniboine River in Canadian Forces Base (CFB) Shilo

Figure 3.43

Vertical air photo: A23692-29

Flight height: 13,700 feet a.s.l.; lens focal length: 153.22 mm

Date: May 12, 1974

Scale: 1:25,000 (approx.)

Location: Townships 7 and 8; Range 15 WI

Map sheets: 1:250,000 62G Brandon 

1:50,000 62G/11 Glenboro

Notes

[i] For details see Kerr, Rounds, and Welsted, op. cit. 1978, 408-414.


 


3.44: Spring Sapping Near Wigle Springs on the Assiniboine River Below Brandon

In this area the Assiniboine 1 has incised itself through the sands of the Assiniboine Delta into the underlying clay. Springs emanate from river cliffs on the outside of the river bend originating at the junction of the permeable sands and impermeable clay. Slow headward erosion by the spring water has led to cliff retreat of about 0.9 miles (1.4 km) in a northerly direction 2. Four nebulously shaped lakes 3 are located in hollows in the flat area left by the cliff retreat. Most of the water finds its way into a small stream 4 that enters the Assiniboine from the northeast. Most of the embayment is wooded 5 as are the banks of the Assiniboine 6. To the north and west of the river is a sand plain 7, but in the southeast relic sand dunes can be seen 8. The plain is mainly grass covered—light-toned 9—with occasional patches of deciduous trees—dark-toned 10. Scattered over the plain are intermediate-toned patches of creeping juniper (Juniperus horizontalis) 11.

The items in a compound 12 are probably associated with Canadian Forces Base (CFB) Shilo just off the photo to the east. Trails across the area are light-toned 13 because vegetation has been removed exposing the underlying sand.

Figure 3.44: Spring Sapping Near Wigle Springs on the Assiniboine River Below Brandon

Figure 3.44: Spring Sapping Near Wigle Springs  on the Assiniboine River Below Brandon

Figure 3.44

Vertical air photograph

Flight height: 11,225 feet a.s.l.; lens focal length: 152.45 mm

Date: August 10, 1965

Scale: 1:20,500 (approx.)

Location: Township 9; Ranges 16 and 17 WI

Map sheets: 1:250,000 62G Brandon 

1:50,000 62G/12 Wawanesa

62G/13 Brandon


3.45: Artesian Groundwater Effects at Catfish Creek at the South End of Lake Winnipeg

Catfish Creek 1 enters Traverse Bay 2 at the south end of Lake Winnipeg. “The stratigraphic sequence…consists of peat at the surface over relatively impermeable lacustrine silt and clay, which in turn overlie relatively permeable sandy outwash or sand till. Bedrock in the immediate area consists of relatively impermeable Precambrian rocks, such as granite and gneiss. Such stratigraphy promotes high artesian pressures in the more permeable layers. Where the surface materials are eroded away along the creek valleys, the overburden pressure is reduced and strongly artesian springs develop. The springs in turn develop craterlike depressions that appear nearly circular when flooded”[i] as along Catfish Creek 3. “The probable groundwater recharge area is located on higher ground to the southwest [4]…where outwash sand and gravel and sandy till occur in a small remnant of end moraine. On this higher ground, ponds and small lakes feed surface waters into the groundwater system. The ground water then migrates down slope toward the northeast, creating increasing artesian pressures in an aquifer that lies between layers of much less permeable material.”[ii]

 

 

A bedrock outcrop, with northwest/southeast trending joints can be seen 5. Sediment plumes can be seen in Traverse Bay 6; sediment is carried to the northwest 7 by the current of the Winnipeg River 8 entering Traverse Bay from the southeast. A small spit- like island—Jackfish Point 9—has developed on the south shore of Traverse Bay; its shape suggests transport of sediment from west to east.

PTH 11 10 follows the south shore of Traverse Bay, passing through Fort Alexander First Nation with the main settlement located at 11. Another gravel road 12 runs way along the east shore of the Bay. Some land has been cleared for agriculture on both sides of the bay 13, but back from the shore the land is mainly wooded 14.

Figure 3.45: Artesian Groundwater Effects at Catfish Creek at the South End of Lake Winnipeg

Figure 3.45: Artesian Groundwater Effects at Catfish Creek at the South End of Lake Winnipeg

Figure 3.45

Vertical air photograph: A24518-199

Flight height: 25,900 feet a.s.l.; lens focal length: 153.22 mm

Date: August 6, 1976

Scale: 1:50,000 (approx.)

Location: Township 19; Ranges 8 and 9 E

Map sheets: 1:250,000 62I Selkirk

1:50,000 62I/9 Pine Falls

Notes

[i] Mollard and Janes, op. cit., 93.

[ii] Mollard and Janes, op. cit., 93.


 


3.46: Glacial Grooving in the Interlake and Westlake Regions

This is a LANDSAT I colour composite made using bands 4 (0.5-0.6 micrometres: green), 5 (0.6-0.7 micrometres: red), and 7 (0.8-1.1 micometres: infrared); consequently infrared radiation is represented in addition to some parts of the visible section of the electromagnetic spectrum. The data was recorded on April 23, 1974 before the leaf-on stage of deciduous trees, but coniferous trees were reflecting infrared radiation producing an orange tinge over much of the image.

At this date Riding Mountain 1 is still snow covered, and most of the water bodies are still ice covered with a surface layer of snow and consequently appear white on the image. Within Riding Mountain National Park, Whirlpool Lake 2, Clear Lake 3, Shoal Lake 4, Lake Audy 5, and Whitewater Lake 6 can be seen. North and east of the park are Dauphin Lake 7, Lake Mantitoba 8, Dog Lake 9, Ebb and Flow Lake 10, Lonely Lake 11, Portage Bay (part of Lake Manitoba) 12, Lake St. Martin 13, Sturgeon Bay (part of Lake Winnipeg) 14, Spence Lake 15, Long Island Bay 16, and Sagemace Bay 17 (part of Lake Winnipegosis 18); and Waterhen Lake 19. All these water bodies are ice and snow-covered, but there are some areas of open water, dark blue in colour, for example, Jackfish Lake 20, the south end of Dauphin Lake 21, and Pineimuta Lake 22. Also there is open water where there is a strong current between water bodies; for example, at the Narrows on Lake Manitoba 23 and just to the south of that 24, south of Peonan Point 25, at Crane Narrows 26, at the Narrows on Lake St. Martin 27, and where the Fairford River flows into Portage Bay 28.

There is also a lot of open water—dark blue—east of Lake Winnipegosis and Waterhen Lake 29 and west of Lake Manitoba 30. The water lies in north/south trending grooves, mapped as intermittent water bodies and marshy areas on topographic maps. The grooves were etched into the Devonian bedrock of the area by southward moving ice, the ice exploiting minor variations in resistance to erosion. These grooves should not be confused with similar features trending generally southeast/northwest along the east and north side of Riding Mountain 31 and Duck Mountain 32. These are Lake Agassiz strandlines deposited after ice had retreated from this area.

In addition to the natural features observed, some land has been cleared for agriculture, for example, at the base of the Riding Mountain escarpment 33, around Dauphin Lake 34, and in the fertile Swan River Valley 35. In these areas the characteristic checkerboard pattern of the DLS is seen.

Figure 3.46: Glacial Grooving in the Interlake and Westlake Regions

Figure 3.46: Glacial Grooving in the Interlake and Westlake Regions

Figure 3.46

Landsat I image

Date: April 23, 1974

This is a colour composite of bands 4—wavelength 0.5-0.6 micrometres (green), 5—wavelength 0.6-0.7 micrometres (red), and 7—wavelength 0.8-1.1 micrometres (infrared)

Scale: 1:1,000,000 (approx.)


3.47: Ground Moraine Topography East of Rapid City

The photograph shows part of the Minnedosa-Reston Till Plain.[i] It includes all or part of sections 3, 4, 5, 8, 9, and 10 of township 13, range 18WI and a very small part of sections 32, 33, and 34 of township 12, range 18WI near the hamlet of Moore Park.

A layer of till, the parent materials for which are Cretaceous shale of local origin, Paleozoic limestone and dolomite from the northeast, and Precambrian rocks from the Canadian Shield to the north, covers much of the surface of southwest Manitoba. “These source materials were probably transported in the basal part of the glacier and deposited as sub-glacial till with a thin capping of ablation till.”[ii] The resulting topography has a low amplitude of relief—less that 50 meters—lacks any integrated drainage system, and contains numerous hummocks and depressions; the latter are frequently occupied by small lakes 1—sloughs in local parlance. On this late summer image many of the sloughs have dried up over the summer 2.

The soils developed on the till are generally black chernozems,[iii] but they vary greatly over short distances depending on the topography and drainage. On the higher ground, at the tops of knolls, much of the fine-grained organic material has been removed by a combination of rain splash and wind erosion. The resulting coarse-grained, light-coloured soils appear light-toned on the photograph 3.

The combination of hummocky terrain and rapid soil variation make large-scale farming difficult. In the east 4 and south 5 much of the land is still wooded, but in other areas arable agriculture is practised. Light-toned fields have been planted to cereal crops 6 (probably wheat given the year of the photograph). In some cases harvesting is underway and stooks have been left in fields 7,[iv] and in another case a field has been partly cut 8. Many fields have been left fallow 9, and in these the light-toned hillcrests are especially marked. This area experiences a dry climate, and, as a result, dugouts have been constructed 10 to provide water, principally for farm animals.

Population density is low; only 3 farms 11 can be identified in the area of just over 4 square miles (10.8 square kilometers). The land is divided into sections with gravel roads along some section lines 12 although in one case there is an anomalous jog to the west 13 to avoid a wooded area. The CP railway line in the south 14 was abandoned long ago.

Figure 3.47: Ground Moraine Topography East of Rapid City

Figure 3.47: Ground Moraine Topography East of Rapid City

Figure 3.47

Vertical air photograph: A11677-23

Flight height: 9420 feet a.s.l.; lens focal length: 153.75 mm

Date: September 3, 1948

Scale: 1:15,500 (approx.)

Location: Townships 12 and 13; Range 18 WI

Map sheets: 1:250,000 62J Neepawa

1:50,000 62J/4 Moore Park

1:125,000 62J/SW Neepawa

Notes

[i] See Welsted, Everitt and Stadel, op. cit., 1996, figure 2.9, 21.

[ii] Mollard and Janes, op. cit. 1984, 49, writing about ground moraine near Medora.

[iii] See Welsted, Everitt, and Stadel, op. cit. 1996 figure 4.3, 46.

[iv] This is an old method of harvesting no longer used.


 


3.48: Ground Moraine Topography South of Minnedosa

This ground moraine area is part of the Minnedosa-Reston Till Plain[i] four miles south-southeast of Minnedosa. It is typical of the Minnedosa pothole region: locally the depressions are referred to as potholes and the lakes within them, as sloughs 1. Many of the potholes contain sloughs surrounded by “emergent aquatic plants such as rushes, sedges, and whitetop” 2.[ii] In some cases this vegetation grades back into shrubs, principally willow (Salix spp) 3. The sloughs and surrounding vegetation zones are excellent waterfowl habitat, but many of the sloughs have evaporated, leaving only a dried out depression 4. There is no integrated drainage system: surface run off is to the nearest slough, which at times of high water may empty into a neighbouring slough.

In contrast to figure 3.47 most of the land has been cleared for agriculture, leaving only a few woodland patches 5. Much of the agricultural land has been left fallow 6, a standard practice at the time the photograph was taken, and in these areas the characteristic bald crests on higher land are very marked 7. They indicate a poorly defined ridge running from north to south through the area. In some parts they exhibit a circular pattern 8. A possible explanation is that stagnant ice broke into blocks; sediment within the ice slurped down the sides of the blocks as they melted forming a ridge surrounding the melting block. These circles are minor relief features; there is only one or two metres difference between the surrounding ridge and its depression.

Grain crops are being grown in several fields 9. The distinctive pattern in the fields results from the harvesting procedure: the grain was cut and left lying in rows 10. A combine then picked up the crop and thrashed it collecting the grain and spilling out straw at the back. The rows of straw are less sharply defined than those resulting from the original cut 11. There are six farms 12, two of which show a very typical arrangement of farm buildings protected from winds by shelterbelts of trees on the north and west 13 with dugouts 14 nearby to supply water.

Gravel roads run along several section lines 15, and sections are divided into quarter sections, sometimes with trees planted along the dividing lines 16. Somewhat unusually the section lines are at an angle to the photo border. Normally flight lines trend east/west or north/south so that section lines are close to the cardinal points of the compass.

Figure 3.48: Ground Moraine Topography South of Minnedosa

Figure 3.48: Ground Moraine Topography South of Minnedosa

Figure 3.48

Vertical air photograph: A18621-114

Flight height: 9,500 feet a.s.l.; lens focal length: 152.13 mm

Date: September 13, 1964

Scale: 1:15,840 (approx.)

Location: Township 14; Ranges 17 and 18 WI

Map sheets: 1:250,000 62J Neepawa

1:50,000 62J/4 Moore Park

1:125,000 62J/SW Neepawa

Notes

[i] See Welsted, Everitt, and Stadel op. cit., 1996, figure 2.9, 21.

[ii] Kiel, Hawkins, and Perret, op. cit., n.d., 35.


 


3.49: Corrugated Ground Moraine South of McAuley

The area shown is located about six miles (9.7 km) south of McAuley near the Manitoba/Saskatchewan border. It exhibits a more definite patterned topography than that shown in figures 3.47 and 3.48. Numerous sloughs emphasize the corrugated appearance of the ground. The sloughs are mainly dark-toned 1 with somewhat lighter tones where emergent vegetation is growing along the edges 2. In the south sloughs are light-toned 3 because the relationship between the angle of the sun, the water surface, and the camera produces the specular reflection effect. Sloughs exist in hollows with low ridges between; the amplitude of relief is only a few meters. “The pattern of ridges is convex to the southeast, indicating that the lobe of ice flowed from the northwest. Intermittent creeks follow the hollows between ridges [4], further emphasizing the transverse orientation of the moraine. Several smaller longitudinal ridges (northwest-southeast) parallel the direction of ice flow and cut across corrugations, creating a reticulate pattern…The corrugations probably formed by pushing and thrusting of material into subglacial zones of weakness near the glacier margin, where the ice was thin and heavily crevassed. The longitudinal ridges are probably the result of the deposition of till in zones of weakness parallel to ice flow, similar to the radial splay crevasses that occur near the front of an ice lobe. Both sets of ridges were preserved by stagnation and melting of the glacier not long after they were formed.”[i] In the west a series of light-toned patches indicate the crest of a discontinuous esker 5.

Much of the land is used for agriculture, and as was the practice at the time, numerous fields are left fallow 6, and in these light-toned bald crests are obvious. Grains probably occupy the light-toned cropped areas. 7 The area lies in townships 13 and 14, ranges 29 and 30 WI. The Manitoba/Saskatchewan border runs along the western edge of range 29 WI, but there is no evidence its existence on the photo. PTH 41 8 runs north/south across the area, three miles east of the provincial border. Section lines can be clearly seen with gravel roads along some of them 9, and quarter sections are picked out by land use differences 10.

Figure 3.49: Corrugated Ground Moraine South of McAuley

Figure 3.49: Corrugated Ground Moraine South of McAuley

Figure 3.49

Vertical air photograph: A15528-51

Flight height: 20,000 a.s.l.; lens focal length: 152.26 mm

Date: October 17, 1956

Scale: 1:36,600 (approx.)

Location: Townships 13 and 14; Ranges 29 and 30 WI

Map sheets: 1:250,000 62K Riding Mountain

1:50,000 62K/3 Miniota

Notes

[i] Mollard and Janes. op. cit., 1984, 48.


 


3.50: Patterned Ground Moraine Near Deloraine

The light-toned circular areas 1 are ice disintegration ridges, formed as ice became stagnant. A probable explanation of their origin is that as ice became stagnant it broke into blocks; sediment within the ice slid down the sides of the blocks as they melted, accumulating as a circular ridge at the ice margin. The resulting ridges are only about 2-3 metres above the surrounding countryside and are barely visible on the ground. They are light-toned because rain splash and wind erosion have removed fine-grained and organic materials from the slightly elevated crests. Their appearance on the photo is enhanced by the fact that almost all the natural vegetation has been removed for agriculture and many fields have been left fallow 2. The circles are not so obvious in fields that are cropped 3. Fields devoted to grain crops are light-toned with a distinctive harvesting pattern 4. The only surface drainage is a small intermittent stream (Medora Creek) 5 that eventually flows into the Souris River west of this area. An artificial drainage ditch 6 enters the creek from the south.

The land in this area is devoted mainly to arable farming: nine farms 7 can be seen in this area of 6.25 square miles (16.2 square km). Typically in this very flat area the farmhouses are protected by shelterbelts 8, built to shield them from cold north and northwest winds in winter. In this dry area there is little surface water, so dugouts 9 have been constructed for farm water supply. Section lines 10, often with gravel roads along them 11, are clearly visible, and quarter sections 12 can sometimes be picked out from land use differences. PTH 21 between Deloraine and Hartney 13 runs north/south through the area. The oval-shaped feature in the southeast corner is the Deloraine racetrack 14. Harness racing is a favourite summer activity in many small communities in southern Manitoba.

Figure 3.50: Patterned Ground Moraine Near Deloraine

Figure 3.50: Patterned Ground Moraine Near Deloraine

Figure 3.50

Vertical air photograph: A16391-97

Flight height: 10,500 feet a.s.l.; lens focal length: 152.63 mm

Date: October 13, 1958

Scale: 1:17,600 (approx.)

Location: Township 3; Range 23 WI

Map sheets: 1:250,000 62F Virden

1:50,000 62F/2 Waskada


3.51: The Brandon Hills, Part of an End Moraine South of Brandon

The Brandon Hills—the dark-toned area in the north-centre of the photograph 1—are the western most extension of the Darlingford Moraine that extends eastwards to Pembina Mountain.[i] They represent a period of still stand in the retreat of ice from Manitoba at the end of the last glaciation. The bulk of the hills are composed of west-northwest/east-southeast trending ridges that are best seen in the west 2. These light-toned ridges are grass-covered whereas most of the area is wooded, resulting in dark tones 3. At the eastern end of the hills is a prominent light-toned north/south trending ridge 4 (see figure 3.52).

The sands and gravels that underlie this ridge are exploited in two gravel pits at either end of the ridge 5. Another gravel pit can be seen at the western end of the hills 6. On the distal side (the side away from the ice front) of the hills are several small lakes 7, one of which—Lake Clementi—8 was a favorite destination for day trips from Brandon in the first half of the Twentieth Century. The hills are surrounded by relatively flat land 9, possibly the floor of a small glacial lake. Drainage is to the east, the main waterway being the Little Souris River 10 that can be picked out because of the dark tone of fringing woodland. Another indefinite area of higher land—mainly wooded and therefore dark-toned—exists on the south 11.

Most of the Brandon Hills are covered with woodland, as the topography is too irregular for agriculture, although encroachment by agriculture into the hills has occurred on both north 12 and south 13 sides. On the north this has resulted in soil erosion 14. An anomalous clearing exists in the east 15; local rumour suggests that there was an attempt to build a landing strip for light aircraft.

The wooded hills are surrounded by agricultural land with the checkerboard pattern of the DLS system. Roads follow section lines, but the hills influence their location; PR 340 between Brandon and Wawanesa locally, termed “The Sunshine Highway,” makes four right-angled bends 16 as it passes round the hills to the east. Only one road—the “Hydro Road” 17 that is followed by hydro lines leading south from a thermal power station in Brandon—crosses the hills from north to south. A side road to the east 18 leads to the start of a series of cross-country ski trails. PTH 10 from Brandon (to the north) to Boissevain (to the south) runs along the west side of the area 19.

Figure 3.51: The Brandon Hills, Part of an End Moraine South of Brandon

Figure 3.51: The Brandon Hills, Part of an End Moraine South of Brandon

Figure 3.51

Vertical air photograph: A24519-179

Flight height: 26,200 feet a.s.l.; lens focal length: 153.22 mm

Date: August 1, 1976

Scale: 1:48,200 (approx.)

Location: Townships 8 and 9; Ranges 18 and 19 WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/12 Wawanesa

Notes

[i] For a detailed description of the Brandon Hills see Welsted, J., and Young, H. R. “Geology and origin of the Brandon Hills, southwest Manitoba.” Canadian Journal of Earth Sciences, vol. 17, no. 7, 1980, 942-951.



3.52: The Eastern Ridge of the Brandon Hills

A sharp-crested ridge exists at the east end of the Brandon hills 1; its sides are very steep, close to the angle of repose of the constituent sands and gravels. These permeable rocks produce a dry environment for plant growth. Consequently the ridge is grass-covered, hence its light tone, but trees exist in wetter, more sheltered draws on the ridge side 2, and they are creeping up the east side 3. The tree cover is a mixture of bur oak (Quercus macrocarpa) and aspen (Populus tremuloides); leaves on the latter are often bright yellow at the date when the photo was taken (October 19) and appear light-toned on the image 4. East of the main ridge are three less definite north/south ridges 5, and east of that the land is flat except for a small outlier of the hills 6. Two small intermittent streams 7 that flow to the Little Souris River (off the photo to the northeast) traverse the flat land.

The flat land is fertile, and most of it is used for crop growth except for some fields that are devoted to animal pasture 8. Harvesting of grain crops is complete, leaving behind distinctive harvesting patterns 9. Very dark-toned fields are those that have been left fallow 10, and even on this very flat land, rain splash and wind erosion have produced light-toned crests on slightly elevated land 11. Six farms 12 exist in this area of 6.25 square miles (16.2 square km). Section lines 13 and quarter section lines 14 are clearly visible; PR 340 15 follows one of the section lines. Railway lines on the other hand do not follow the survey system; the CN line 16, long ago abandoned, connected Brandon and Wawanesa. It takes an unexpected loop in the north 17, possibly to meet the Little Souris River just off the photo, at an appropriate point.

Figure 3.52: The Eastern Ridge of the Brandon Hills

Figure 3.52: The Eastern Ridge of the Brandon Hills

Figure 3.52

Vertical Air photograph: A16408-10

Flight height: 10,500 feet a.s.l.; lens focal length: 152.63 mm

Date: October 19, 1958

Scale: 1:17,600 (approx.)

Location: Townships 8 and 9; Range 18 WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/12 Wawanesa


3.53: The Brandon Hills From the East

This high oblique photograph (labeled “high” because the horizon is shown) of the Brandon Hills was taken looking to the southwest. In the foreground is the now abandoned railway line 1 between Brandon and Wawanesa, and running across the middle of the photo is PR 344 2 between the two communities. In the background is the dark-toned tree-covered mass of the Brandon Hills 3 with the light-toned, grass covered, eastern ridge 4. Nearer to the viewer is a complex of ridges 5, the crests of which are grass-covered and the furrows between, wooded. As the photograph was taken in the winter, there is a thin skiff of snow on the agricultural land in the foreground 6 that is traversed by a small intermittent stream 7, frozen at this time of year.

Figure 3.53: The Brandon Hills From the East

Figure 3.53: The Brandon Hills From the East

Figure 3.53

Oblique air photograph

Date: December 6, 1965

Scale: Variable—larger in the foreground and decreasing in the rear

Location: Townships 8 and 9; Ranges 18 and 19 WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/12 Wawanesa


3.54: The Tiger Hills West of Belmont

The Tiger Hills 1, part of the Darlingford end moraine, run in an arc from the northwest corner of the photo to the southeast. Their hummocky form means that they have mainly been left in a wooded state—dark toned on the photo 2. On their proximal side—side in contact with the ice, which advanced from the northeast—is a series of lakes 3, the largest of which is Lloyd’s Lake 4. Lakes further east 5 are shown as being intermittent on the 1:50,000 map (62G/5 Dunrea) of the area, although their dark tone indicates that they were water filled at the time the photo was taken. Northeast of the end moraine is ground moraine 6 with a definite northwest/southeast alignment of ridges and lake-filled furrows 7. Southwest of the end moraine is the Souris-Pembina Spillway 8 that has steep banks and a flat floor, partly occupied by Bone Lake 9, Overend Lake 10, and Pelican Lake 11. Specular reflection produces a light-toned area at the north end of Pelican Lake 12. In the east/west part of the spillway the south bank (north facing) is heavily wooded (dark-toned) 13 because of its wet microclimate, whereas the south-facing slope is only partly tree covered 14. Both the south bank 15 and the north bank 16 are dissected by tree-covered gullies 17.

Three small settlements exist in the area; Dunrea 18 and Ninette 19 are connected by the CN railway line 20, and in the northeast Hilton 21 lies just north of a long abandoned railway line 22. PTH 23 23 runs east/west across the area, south of Dunrea and through Ninette. PTH 18 24 runs north/south.

Figure 3.54: The Tiger Hills West of Belmont

Figure 3.54: The Tiger Hills West of Belmont

Figure 3.54

Vertical air photograph: A21808-67

Flight height:  lens focal length:

Scale: 1:79,200 (approx.)

Date:

Location: Townships 5 and 6; Ranges 16 and 17WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/5 Dunrea


3.55: The Tiger Hills Near Baldur

The Tiger Hills are part of the Darlingford moraine that runs across southern Manitoba from the Brandon Hills in the west to Pembina Mountain in the east. The hills occupy the central part of this image and are characterized by hummocky terrain, much of which is too hilly for agriculture. Consequently much of the land is left wooded and is dark-toned 1. Depressions are occupied by numerous lakes, some of which are large enough to be named on the 1:250,000 topographic map: McLean Lake 2, the northern part of which is light-toned and the south, dark; Breaults Lake 3; Hoseas Lake 4; and Jones Lake 5. The lakes vary in tone from almost black 6—these are deep with little suspended sediment—to dark grey 7, shallower with suspended sediment, to almost white 8—these illustrate the effect of specular reflection. The ice from which the Tiger Hills moraine was deposited advanced from the north and left behind a series of lobate ridges 9.

North of the moraine is flatland, part of the Assiniboine Delta deposited into glacial Lake Agassiz. Lakes are fewer but one large one, Goodmans Lake 10, can be seen in the north/centre. It is partly unfilled by emergent vegetation. Near the northern edge of the photo is Glenboro Marsh 11 that empties into Oak Creek 12 that flows northwest to the Assiniboine (off the image to the northwest). The lowland occupied by Oak Creek, Glenboro Marsh and Cypress River (just off the northeast corner of the photo) represents the position of a distributary of the Assiniboine at the time the Assiniboine Delta was formed.

On this high-level, small-scale photo the DLS system is obvious especially in areas devoted to agriculture. In the hills, however, the roads cannot always follow section lines as they are forced to detour around lakes 13. Several major route ways can be seen. PTH 23 14 runs east/west and PTH 5 15 north/south across the area. The CN line 16 enters from the southwest and then follows the same route as PTH 23. In the northeast corner a very faint line 17 indicates the position of an underground oil pipeline.

The small Icelandic settlement, Baldur 18, is located south of the hills. It is laid out in grid form with roads parallel and at right angles to both the highway and railway line.

Figure 3.55: The Tiger Hills Near Baldur

Figure 3.55: The Tiger Hills Near Baldur

Figure 3.55

Vertical air photo: A21808-64

Flight height: 24,400 feet a.s.l.; lens focal length: 85.55 mm

Date: August 6, 1970

Scale: 1:82,300 (approx.)

Location: Townships 5 and 6; Ranges 13 and 14 WI

Map sheets: 1:250,000 62G Brandon 

1:50,000 62G/11 Glenboro

62G/6 Baldur


3.56: Drumlins and Eskers in Northern Manitoba

Much of northern Manitoba is covered by a thin—in some cases very thin—layer of glacial drift. On this photo bedrock can be seen in the west 1 and east 2. In both cases northwest/southeast lineations can be seen (3 and 4). The general alignment of the topography is north-northeast/south-southwest and in two areas the surficial glacial deposits have been pulled into drumlinoid forms 5. Drumlins are thought to have been formed beneath an ice sheet which was sufficiently active to produce the characteristic elongate form. Numerous lakes—dark-toned—can be seen in the areas occupied by drumlins. The lakes have the same north-northeast/south-southwest alignment 6. Two eskers 7 and 8 can be seen. These ridges were deposited by water under or within the ice sheet and then dropped onto the underlying topography. Sandy sediments have been deposited on either side of one of the eskers producing light-tone areas on the photo 9.

The dark-toned triangular shaped area in the southeast corner 10 is a technical defect.

Figure 3.56: Drumlins and Eskers in Northern Manitoba

Figure 3.56: Drumlins and Eskers in Northern Manitoba

Figure 3.56

Vertical air photograph: A15707-12

Flight height: 30,000 feet a.s.l.; lens focal length: 152.56 mm

Scale: 1:60,000 (approx.)

Date: July 23, 1957

Location: 59°53'26"N, 100°24'53"W

Map sheets: 1:250,000 64N Kasmere Lake

1:50,000 64N/16 Bagg Lake


3.57: Drumlinized Ground Moraine South of Holland and Treherne

Nowhere in southern Manitoba are found the classic “inverted spoon” shaped drumlins described in many elementary textbooks. However, immediately south of Holland 1 and Treherne 2 is an area of drumlinized ground moraine. Ridges composed of glacial till have a northwest/southeast alignment 3. The resulting topography has a rolling form—characteristic of drumlin areas—with an amplitude of relief up to 150 feet (46 m)—substantial for southern Manitoba. Lakes are not abundant; the only one large enough to be named on the 1:250,000 map, Pinkerton Lake 4, is south of the main drumlinized area.

The land north of a line joining Holland and Treherne is flat, part of the Assiniboine Delta. Cutting across the northern edge of the drumlinized area is a deep depression 5, up to 100 feet (30.5 m) below the surrounding land. It contains two intermittent lakes 6 and 7 hardly visible on the photo because they were dry at the time. Water from these drains into the Boyne River 8 that bypasses Treherne to the northwest. This lowland is clearly superimposed upon the drumlinized area; it is therefore later in origin, probably originating as the valley of a distributary of the Assiniboine at the time its delta was formed. Near the northern edge a deep gully, Bears Paw Gulch 9, is etched into the deltaic deposits.

On this high-level, small-scale photo, the sections of the DLS system are clearly visible, especially on the flatland of the delta, which is devoted to arable agriculture. Farmsteads with surrounding shelterbelts 10 are clearly visible. A correction line of over 0.25 mile (0.4 km) exists between townships 6 and 7 11. Correction lines, which are located between townships 2 and 3, 6 and 7, 10 and 11, etc., exist to compensate for the convergence of the meridians (on which range line are based), whereas north/south section lines are always one mile apart.[i] The correction line influences the location of PTH 34 12, which runs along a section line in township 6, then jogs westward by the correction distance and the width of an additional section 13 before continuing northward. The main east/west road is PTH 2 14 that bypasses both Treherne and Holland. The CP railway line follows the same route, except that it runs through both villages 15. All the roads in Treherne 2 are parallel or at right angles to the railway, whereas in Holland 1 the older roads are oriented with respect to the railway line; but newer roads in the south follow the lines of the DLS system.

Figure 3.57: Drumlinized Ground Moraine South of Holland and Treherne

Figure 3.57: Drumlinized Ground Moraine South of Holland and Treherne

Figure 3.57

Vertical air photo: A21666-219

Flight height: 23,400 feet a.s.l.; lens focal length: 88.611 mm

Date: July 21, 1970

Scale: 1:75,400 (approx.)

Location: Townships 6 and 7; Ranges 10 and 11 WI

Map sheets: 1:250,000 62G Brandon 

1:50,000 62G/10 Treherne

Notes

[i] For details see Richtik, J. M. “The Township and Range Survey System” in Welsted, Everitt, and Stadel, op cit. 1996, 102-103.


 


3.58: An Esker in Northwestern Manitoba

Eskers are linear ridges deposited by water in tunnels in or under ice sheets. Although they are not particularly high—heights are in metres or tens of metres—they are striking features of the landscape of northern Manitoba often running for tens of kilometres across the land seemingly heedless of the underlying topography on to which they have been superimposed.

This photograph taken near the northern border (60°N) of Manitoba is of an area of drift-covered bedrock. An esker 1 runs the whole width of the photo from north to south. This makes it 8 miles (12.9 km) long, but inspection of the 1:250,000 map of the area (64N Kasmere Lake) reveals that it is 20 miles (32 km) long. In the north, the esker forms the western shore of Putahow Lake 2 into which drains the Putahow River 3 after traversing a series of rapids 4 which are bypassed by Husky Portage 5. This esker is not a single ridge; in two places (6 and 7) it splits into two or more ridges. Another smaller esker 8 runs across part of Putahow Lake. In this area and to the north and west the land has a drumlinized appearance 9, several of the mounds poking above the lake level 10.

This area lies within the forest sub-zone of the forest/tundra transition vegetation zone.[i] The vegetation consists of open lichen woodland; dark areas 11 are patches of woodland, whereas light-toned patches 12 are lichen-covered ground.

The dark area in the southeast 13 is a technical defect, either in taking or in printing the photo.

Figure 3.58: An Esker in Northwestern Manitoba

Figure 3.58: An Esker in Northwestern Manitoba

Figure 3.58

Vertical air photograph: A15707-15

Flight height: 30,000 feet a.s.l.; lens focal length: 152.56 mm

Date: July 23, 1957

Scale: 1:57,900 (approx.)

Location of centre point: 59° 53'N, 100° 43'W

Map sheets: 1:250,000 64 N Kasmere Lake

1:50,000 64 N/15 Putahow Lake

Notes

[i] See Scott, G. A. J. “Manitoba’s Ecoclimatic Regions” in Welsted, Everitt and Stadel. op. cit. 1996, figure 4.2, 45.


 


3.59: An Esker in Northeastern Manitoba

The main esker 1 traversing the area on this photo trends north-northeast/south-southwest and is 9 miles (14.5 km) long, but the 1:250,000 map of the area (64P Nejanilini Lake) shows that it extends discontinuously for almost twice that length. It consists of one major ridge with a bifurcation 2 and light-toned sandy/gravelly deposits on either side 3. Another shorter esker 4 joins the main one from the northwest. Both have been superimposed on the underlying bedrock topography, and in the north the larger esker divides a large lake into two parts (5 and 6).

The Gordon River 7 flows in a general west to east direction across the area that is dotted by numerous lakes, variable in tone. Radcliffe Lake 8 and lakes to the west 9 and north 10 of it, as well as Gorrie Lake 11 and several lakes near the southern edge of the photo 12, are light grey which probably indicates that they are shallow, whereas some of the other lakes 13 are dark-toned because they are deeper.

This area lies within the shrub sub-zone of the forest/tundra transition vegetation zone[i] in which “a shrub tundra like community dominates, together with small open clumps of white or black spruce in more sheltered sites.”[ii] On the photograph the wooded areas are the dark-toned patches lying mainly along the watercourses 14.

Figure 3.59: An Esker in Northeastern Manitoba

Figure 3.59: An Esker in Northeastern Manitoba

 

Figure 3.59

Vertical air photograph: A15460-17

Flight height: 30,000 feet a.s.l.; lens focal length: 154.3 mm

Date: August 21, 1956

Scale: 1:58,000 (approx.)

Location of centre point: 59° 28'N, 97° 06'W

Map sheets: 1:250,000 64 P Nejanilini Lake

1:50,000 64 P/6 Fallis Lake

 

Notes

[i] Scott, op. cit. 1996, figure 4.2, 45.

[ii] Scott, op. cit. 1996, 53.



3.60: The Russell Esker Near the Caribou River in Northeastern Manitoba

The water body on the right 1 is Long Lake, part of the Caribou River system that flows into Hudson Bay about 25 miles (40 km) to the east. A prominent esker 2 can be seen trending southwestward from the shore of the lake. Its total length is about 18 miles (29 km) less than half of which is shown on the photo. It is prominent enough that is has been named the Russell Esker. In common with many other eskers in northern Manitoba, there is good hiking along the crest. At its northern end 3 there is a caribou crossing of the river as recorded by Wilson and Ackroyd. “At Long Lake we camped at a busy caribou crossing and watched for two days while small groups swam the narrows of the lake.”[i] Another small patch of esker-like deposits occurs west of the main esker 4.

This area is in the shrub zone of the forest/tundra transition vegetation zone[ii] in which a “shrub tundra like community predominates.”[iii] On the photograph the shrub areas 5 are slightly darker-toned than the surrounding areas.

Figure 3.60: The Russell Esker Near the Caribou River in Northeastern Manitoba

Figure 3.60: The Russell Esker Near the Caribou River in Northeastern Manitoba

Figure 3.60

Vertical air photo: A14678-106

Flight height: 30,000 feet a.s.l.; lens focal length: 152.7 mm

Date: July 2, 1955

Scale: 1:59,000 (approx.)

Location of centre point: 59° 26'N, 95° 31'W

Map sheets: 1:250,000 54 M Caribou River

1:50,000 54 M/5 Gross Lake

Notes

[i] Wilson and Aykroyd, op. cit. n.d., 138.

[ii] Scott, op. cit., 1996, figure 4.2, 45.

[iii] Scott, op. cit., 1996, 53.



3.61: The Robertson Esker in Northwestern Manitoba

This image is different from those in figures 3.59, 3.60, and 3.61 in that it is an oblique photograph—technically a high oblique because the horizon 1 is shown. As the name suggests the camera was pointed obliquely rather that straight down as was the case in most photographs shown so far. In some ways an oblique is a more realistic view, more like the view a person gets when looking from a plane window. However, from an interpreter’s point of view obliques have problems. The scale is large in the foreground (in this case about 1:37,500) but decreases progressively away from the camera. This makes it difficult to calculate ground distances and areas.

The photograph was taken looking just south of east and shows another of Manitoba’s named eskers—the Robertson Esker 2, running northeast/southwest across the foreground. It is a very long esker traversing almost the whole of the 1:250,000 map sheet 64K, Whiskey Jack Lake, and extending into the sheet to the south 64F, Brochet. It is recognizable as a discontinuous northeast/southwest ridge running across 80 miles (129 km) of the northern Manitoba landscape. In some places it has a single ridge form 3 as where it forms the southeast shore of Ducharme Lake 4, but both to east 5 and west 6 of that it bifurcates. Eskers are composed of sands and gravels and are characteristically light-toned where they are not covered by vegetation 7. A much smaller esker 8 can be seen on the right of the photo.

This lake-strewn area falls in the open lichen woodland vegetation zone in which “the better drained upland ground cover is dominated by fructose lichens…between…scattered spruce.”[i] This arrangement can be seen in the left foreground 9, but in the background the scale is too small to distinguish details.

Figure 3.61: The Robertson Esker in Northwestern Manitoba

Figure 3.61: The Robertson Esker in Northwestern Manitoba

Figure 3.61

Oblique air photo: T104 R-55

Flight height: 20,000 feet a.s.l.; lens focal length: 6 inches

Date: September 11, 1946

Scale: 1:37,500 (approx.) in the foreground, decreasing towards the rear

Location of centre point: 58° 11'N, 100° 43'W

Map sheets: 1:250,000 64K Whiskey Jack Lake

1:50,000 64K/2 Ducharme Lake

Notes

[i] Scott, op. cit., 1996, 51-52.


 


3.62: The Arrow Hills North of Oak Lake

The Arrow Hills are a north-northwest/south-southeast trending range of hills. In this area the hills consist of a single sharp-crested ridge 1, but further north (off the photo) the ridge splits into a complex of less clearly defined ridges and depressions. At this location the ridge stands 125 feet (38 m) above the surrounding countryside and has been interpreted as a crevasse filling dropped onto the underlying topography as ice began to disintegrate. It is composed of permeable sands and gravels that present too dry an environment for tree growth. Consequently it is covered by grasses—light-toned 2—with clumps of trees—dark-toned 3—in slightly wetter depressions or “draws” on the ridge side. Some of the bluffs of trees contain lighter-toned trees 4 that are probably aspen (Populus tremuloides) whose leaves turn to yellow in the fall. The direction of a small stream 5 is controlled by the ridge that it follows southeastward before entering the Assiniboine (off the photo to the south). To east and west of the ridge is typical ground moraine topography with depressions occupied by sloughs 6, many of which have dried up 7.

Off the ridge and outside the stream valley, much of the land has been cleared for arable agriculture. Grain crops have been grown and harvested and following the practice of the times, straw piles 8 have been deposited in several fields. In one case a farmer has been cultivating a field 9 in preparation for next year’s crop. Eight farms 10 can be seen, several with typical shelterbelts located to north and west. The section lines of the DLS system are clearly visible with gravel roads following some of them. PR 254 18 between Oak Lake and Lenore is the main transport route in the area. A small building west of PR 254 is identified as a small church 19 on the basis of its pointed shadow.

Figure 3.62: The Arrow Hills North of Oak Lake

Figure 3.62: The Arrow Hills North of Oak Lake

Figure 3.62

Vertical air photograph: A16429-47

Flight height: 10,500 feet a.s.l.; lens focal length: 152.63 mm

Date: October 29, 1958

Scale: 1:17,100 (approx.)

Location: Township 10; Range 24 WI

Map sheets: 1:250,000 62F Virden

1:50,000 62F/15 Virden


3.63: The Arrow Hills From the Northeast

This oblique photograph—technically called a low oblique because the horizon is not shown–was taken looking towards the southwest. The main ridge of the hills can be seen in the middle ground 1 with the course of a small stream—dark-toned—to the west 2. In this winter image, the sun angle is very low, producing long shadows 3. There is a thin snow cover over most fields resulting in the very light tone, although part of the field in the foreground has been blown clear revealing the dark-coloured chermozenic soil of the area 4. PR 254 5 has also been kept clear by vehicular traffic.

Figure 3.63: The Arrow Hills From the Northeast

Figure 3.63: The Arrow Hills From the Northeast

Figure 3.63

Oblique (low) air photo

Date: December 6, 1965

Scale: 1:18,600 in the foreground, decreasing to the rear

Location: Township 10; Range 24 WI

Map sheets: 1:250,000 62F Virden

1:50,000 62F/15 Virden


3.64: Gravel Pits in the Birds Hill Esker Northeast of Winnipeg

“Perhaps the best known esker [in Manitoba] is that at Birds Hill, 16 kilometres northeast of Winnipeg. Here a high narrow ridge of sand and gravel extends 6.5 kilometres east from Birds Hill and then merges into a delta-shaped plateau that extends over a broad area underlying Birds Hill Park. The esker is the main source of aggregate material for the city of Winnipeg.”[i] The esker/delta is composed of sands and gravels which when exposed in excavations appear light-toned. This large-scale photo covers too small an area for the landform of the deposits to be revealed, but several large gravel pits excavated into the southern part of the complex 1 are obvious. In several cases abandoned excavations have filled with water to produce shallow, light-toned lakes2 and deeper, dark-toned, lakes 3. There is little obvious surface drainage in the area, but in two cases it looks as if small streams have been directed into artificial channels 4. The long narrow medium-toned areas 5 are the fairways of a golf course—the Pine Ridge course. Some arable agriculture is practised in fields surrounding the excavations 6. PR 213 7 runs along the section line between townships 11 and 12 west to Birds Hill, just off the photo, and a railway line 8 crosses the northwestern corner of the photo.

Two questions remain for the interpreter: what are the white dots in the northeast 9 and what are the white streaks 10 in the south.

Figure 3.64: Gravel Pits in the Birds Hill Esker Northeast of Winnipeg

Figure 3.64: Gravel Pits in the Birds Hill Esker Northeast of Winnipeg

Figure 3.64

Vertical air photograph: A27254-131

Flight height: 13,300 feet a.s.l.; lens focal length: 152.033 mm

Date: April 14, 1988

Scale: 1:24,400 (approx.)

Location: Townships 11 and 12; Ranges 4 and 5 EI

Map sheets: 1:25,000 62H Winnipeg

1:50,000 62H/15 Dugald

Notes

[i] Corkery, T M. op. cit. 1996, 11-22.



3.65: Outwash Plateau South of the Qu’Appelle River

The photograph shows an extensive area of outwash deposits, west of the Assiniboine River and south of the Qu’Appelle Valley in the extreme west of Manitoba 1. Outwash sediments were deposited by water running from melting ice. This usually results in a surface with a rippled appearance as seen in the south 2, but in the north the surface is flat 3. Outwash deposits in Manitoba are usually too dry to be suitable for arable agriculture. Most of the surface is covered by medium-toned grass 4 but some wetter areas support trees—dark-toned 5. Circular dark patches 6 are probably clumps of creeping juniper (Juniperus horizontalis).

The outwash forms a plateau with abrupt edges 7. To the north and southwest, trees are more abundant in a wetter environment probably resulting from water reaching the surface at the contact between permeable sands and gravels above with less permeable clay below. The Qu’Appelle River 8 runs west to east across the north of the area, occupying a steep-sided 9, flat-floored spillway. It meanders freely across the spillway floor leaving behind six clearly defined oxbows 10 as well as one abandoned river segment 11 and numerous less distinct older abandoned channels.

In contrast to many previous photos the DLS system is not obvious but several faint section lines 12 and quarter section lines can be seen. The fifth base line of the DLS 13 separates townships 16 and 17. PTH 41 14 between McAuley (off the photo to the south) and St. Lazare (off the photo to the north) runs across the area. Light-toned areas 15 are road cuts where PTH 41 descends the steep south bank of the Qu’Appelle spillway. PR 545 16, a faint light-toned line, runs east/west. North of the Qu’Appelle River, the CN railway line runs along the foot of the north bank of the spillway 17 with sidings into a large light-toned gravel pit 18.

Figure 3.65: Outwash Plateau South of the Qu’Appelle River

Figure 3.65: Outwash Plateau South of the Qu’Appelle River

Figure 3.65

Vertical air photograph: A15530-13

Flight height: 20,000 feet a.s.l.; lens focal length: 152.26 mm

Date: October 9, 1952

Scale: 1:39,700 (approx.)

Location: Townships 16 and 17; Range 29WI

Map sheets: 1:250,000 62K Riding Mountain

1:50,000 62 K/6 Birtle


3.66: Outwash Plateau at the Hudson Bay Company Reserve at Fort Ellice

The plateau shown here is a southward extension of that shown on figure 3.65. The plateau has a sharp edge 1; in the north the surface has the typical mottled appearance of outwash deposits 2 but in the south the surface is flatter 3. Grassland covers almost all the plateau surface; a dugout 4 in the east suggests that the area is used as animal pasture.

A small stream that drains east to the Assiniboine River (off the photo) 5 has eroded a large valley that surrounds the plateau. The southern side of the valley (north-facing) is covered by deciduous woodland 6, but the south-facing side is much drier resulting in the formation of dunes 7. The linear pattern in the north 8 results from clearing of woodland, the dark lines 9 being trees that have been left standing and the white lines 10 piles of cut wood.

Straight lines bound the Hudson Bay Company Reserve to south 11, west 12, and north 13. The reserve extends to the Assiniboine that forms its eastern boundary. There is little evidence of transport routes except for a path (light-toned) 14 that crosses the plateau and then runs down the valley side 15.

Figure 3.66: Outwash Plateau at the Hudson Bay Company Reserve at Fort Ellice

Figure 3.66: Outwash Plateau at the Hudson Bay Company Reserve at Fort Ellice

Figure 3.66

Vertical air photograph: A18623-11

Flight height: 9,500 feet a.s.l.; lens focal length: 152.13 mm

Date: September 13, 1964

Scale: 1:16,350 (approx.)

Location: Township 16; Range 28 WI

Map sheets: 1:250,000 62K Riding Mountain

1:50,000 62K/6 Birtle


3.67: Outwash Channels South of Baldur

This high-level, small-scale photo shows a series of outwash channels 1 merging into a single channel 2, today occupied by a small unnamed stream that runs into the Pembina Valley, occupied here by Rock Lake 3. The channels resulted from water emanating from a decaying ice sheet to the north. In the northeast is typical end moraine topography—part of the Tiger Hills—with numerous lakes in depressions. As has been the case on several previous photos, lakes in the area vary in tone; specular reflection produces some almost white-toned lakes 4, shallow lakes such as Fisher Lake 5 are medium-toned, and deeper lakes 6 are dark-toned. Some lakes, such as Allards Slough 7, have been partially unfilled by vegetation.

There is a marked contrast in land use between that on the end moraine areas and that on areas underlain by outwash. The hummocky terrain and the large number of lakes on the end moraine make arable agriculture difficult, and much of the land is tree or grass covered. The outwash areas are free of lakes and relatively flat; consequently much of the land has been cleared for agriculture, for example, between the outwash channels 8 and in the southeast. Fields in both areas are small with quarter-section sections divided into many fields 9. This contrasts with the situation in some parts of southwestern Manitoba where a single field often occupies a quarter-section.

On this small-scale photo the sections of the DLS system are very visible. Roads in the main follow section lines, for example, PTH 5 10 in the west and PR 342 11 in the east. PTH 23 12 can just be seen at the northern edge of the photo, as can the southern part of Baldur 13. The CN line is visible in the northeast 14 with a spur 15 branching off to the southwest near Greenway 16. It follows a somewhat indirect route south to Rock Lake and then continues to the west to finish at Ninette.[i]

As this photo is the first in a job, details are given on the bottom left hand corner. The flight height was 24,100 feet above sea level; line 3 (photos A21852-1 to 17) was flown from west to east on August 12, 1970, as was line 8 (photos A21852-18 to 38). The camera lens had a focal length of 85.55 mm and a dark yellow filter was used.

Figure 3.67: Outwash Channels South of Baldur

Figure 3.67: Outwash Channels South of Baldur

 

Figure 3.67

Vertical air photograph: A21852-1

Flight height: 24,100 feet a.s.l.; lens focal length: 85.55 mm

Date: August 12, 1970

Scale: 1:79,200 (approx.)

Location: Townships 3 and 4; Ranges 13 and 14 WI

Map sheets: 1:250,000 62G Brandon 

1:50,000 62G/6 Baldur

 

Notes

[i] In many cases railway lines identified on the air photos in this collection are no longer in use. However, they are mentioned because of their historical relevance to the area in which they are located.



3.68: Assiniboine Delta Edge and Lake Agassiz Strandlines Near Miami

In this high-level, small-scale photo, the lakeward edge of the Assiniboine Delta deposited into glacial Lake Agassiz at the end of the ice age can be seen trending northwest/southeast across the area 1. This relatively steep slope is wooded and hence dark-toned. Three wooded stream valleys dissect the delta edge; from north to south they are South Tobacco Creek 2, an unnamed stream 3, and Shannon Creek 4. Thornhill Coulee 5 can also be seen in the southeast corner.

Northeast of the delta edge, several Lake Agassiz strandlines can be seen 6. The neutral term “strandline” is used because it is not clear whether they were deposited as beaches or offshore bars. Lake Agassiz retreated to the northeast, so strandlines in the west are at a greater elevation and earlier in origin than those further east. The strandlines stand out because of tonal variations that represent soil and land use variations. Although they are noticeable on the photo, their relief is only a metre or so, and they can easily be missed on the ground. East of the lowest strandline is typical very flat lake floor topography 7 with the only relief being the valleys of small intermittent streams 8.

The land is divided into the one-mile squares of the DLS system, and apart from the delta edge and some stream valleys, the land is intensively farmed, especially in the east where sections are divided into many fields 9. The hamlet of Miami 10 in the north is the only settlement in the area which is crossed by the east/west trending PTH 23 12. Elsewhere gravel roads follow section lines except where they cross the delta edge 13. The CN line 14 follows PTH 23 through Miami before veering off to the north to cross a strandline at an angle.

Figure 3.68: Assiniboine Delta Edge and Lake Agassiz Strandlines Near Miami

Figure 3.68: Assiniboine Delta Edge and Lake Agassiz Strandlines Near Miami

Figure 3.68

Vertical air photograph: A21852-10

Flight height: 24,100 feet a.s.l.; lens focal length: 85.55 mm

Date: August 12, 1970

Scale: 1:84,500 (approx.)

Location: Townships 3, 4, and 5; Ranges 5, 6, and 7 WI

Map sheets: 1:250,000 62G Brandon 

1:50,000 62G/8 Miami


3.69: The Arden Ridge East of Birnie

Some of the Lake Agassiz strandlines are so prominent that they have been given names. One such is the Campbell Beach, a prominent ridge which stands as much as 10 metres (32.8 feet) above the surrounding land. In the area shown here the Campbell Beach is referred to as the Arden Ridge because it runs through the small settlement of Arden located 7 miles (11 km) south of the photo. A gravel road, PR 352 1 between Arden and Birnie follows the ridge on the east side of the photo. Its direction contrasts sharply with the normal north/south and east/west trending roads in the area. Other strandlines to the east 2 are at a lower elevation and are more recent, whereas strandlines in the west 3 are higher and older. The CN line 4 near Birnie 5 follows the strandline direction in the north before veering off to the west in the south.

Drainage in the area is generally from the higher land in the west to lower land in the east. Several small creeks can be seen 6, one of which is deflected south by the Arden Ridge 7. However, Birnie Creek 8 in the north flows across the strandlines without interruption, but in the northeast it has been straightened 9 to improve its flow rate. One small creek has been dammed to create a reservoir 10 for water supply at a neighbouring farm. Land between the two sets of strandlines is dry; consequently, much of it has been left with a scrub cover 11. In order to improve water supply—mainly for use by cattle—numerous dugouts (small black rectangles on the photo) have been excavated 12.

As is usually the case with photos of southern Manitoba, section lines 13 and quarter-section lines 14 can be seen. Section lines are marked by a road allowance of 99 feet often not used in this area 15, whereas quarter-section lines are usually picked out by land use variations 16. The fifth baseline of the DLS between townships 16 and 17 runs across this area 17.

Figure 3.69: The Arden Ridge East of Birnie

Figure 3.69: The Arden Ridge East of Birnie

Figure 3.69

Vertical air photograph: A15225-11

Flight height: 20,000 feet a.s.l.; lens focal length: 152.26 mm

Date: May 24, 1956

Scale: 1:37,300 (approx.)

Location: Townships 16 and 17; Ranges 14 and 15 WI

Map sheets: 1:250,000 62J Neepawa

1:50,000 62J/6 Arden


3.70: Lake Agassiz Strandlines Along the Northeastern Edge of Riding Mountain National Park

On this photo Riding Mountain National Park (RMNP) is in the southwest, its boundary 1 marked by cutlines through the forest. At least five strandline zones 2, 3, 4, 5, 6 can be identified, the highest and oldest being in the southwest 2. As Lake Agassiz retreated to the northeast, it left behind strandlines whose prominence depends on how long the lake stood at a particular level; large prominent ridges indicate a long period of still stand. In the highest zone 2 are several individual lines 7, and below the lowest zone 6, tonal variations in cleared fields 8 indicate very low ridges which may have originated as offshore bars.

Within the park all the land is covered by coniferous/deciduous woodland, the darker toned patches 9 indicating stands of coniferous trees. Outside the park some land has been cleared for agriculture. In the fields the strandlines show up as light-toned areas 10 where dark-coloured soil particles have been removed by rain splash and wind erosion. The Ochre River 11 drains from the central part of RMNP to Dauphin Lake (off the photo to the northeast). It meanders and has deposited shale eroded from the highlands on the insides of bends resulting in light-toned areas 12. A straight drainage channel 13 has been excavated parallel to the general trend of the strandlines.

The boundary between townships 22 and 23 runs across the area. It is the sixth correction line in the DLS system, corrections being about three quarters of a mile (1.2 km) 14. Section lines 15 and quarter-section lines 16 can be seen. Several farms can be identified 17, but there are no nucleated settlements in the area.

Figure 3.70: Lake Agassiz Strandlines Along the Northeastern Edge of Riding Mountain National Park

Figure 3.70: Lake Agassiz Strandlines Along the Northeastern Edge of Riding Mountain National Park

Figure 3.70

Vertical air photograph: A15229-23

Flight height: 20,000 feet a.s.l.; lens focal length: 152.26 mm

Date: June 4, 1956

Scale: 1:37,300 (approx.)

Location: Townships 22 and 23; Ranges 17 and 18 WI

Map sheets: 1:250,000 62J Neepawa

1:50,000 62J/13 Laurier

1:125,000 MCR 207 Riding Mountain National Park


3.71: Lake Agassiz Strandlines Southwest of Ashville

This area is part of the lowland between Riding Mountain to the south and Duck Mountain to the north. Lake Agassiz strandlines, which run along the Riding Mountain and Duck Mountain escarpments, bend westward into the lowland. On this photo a small segment of the Campbell Beach followed by PTH 10 can be seen in the northeast 1. Another group of strandlines can be seen in the centre and south of the photo 2; in the south they swirl around an area of higher land 3 which must have been an island when they were formed. The group has a sharply defined northeastern edge 4 and to the west and south, individual strandlines are identified on the basis of land use differences 5 or variation in tone in the agricultural fields 6. Drainage in the area is generally from west to east: Wilson Creek 7 drains eastward to Dauphin Lake (off the photo to the east) and is joined from the south by an intermittent stream, Mineral Creek 8. In the northwest are two other intermittent streams (9 and 10).

Most of the area has been cleared for agriculture, but some dark-toned patches of trees remain, even on what appears to be flat, good agricultural land 11 as well as in the area of the strandlines 12 and along stream channels 13. Section lines of the DLS system are clear; they determine the direction followed by roads in the area. PTH 5 14 crosses the area following section lines except where it crosses Wilson Creek 15. PTH 10 16 branches off to the north, passing through the hamlet of Ashville 17 after which it follows the Campbell Beach. The east/west trending CN line 18 also passes through Ashville. Further south a broad light-toned line 19 indicates the route followed by an above surface power line; a little further north a very thin light-toned line 20 represents the route followed by an underground pipeline.

Figure 3.71: Lake Agassiz Strandlines Southwest of Ashville

Figure 3.71: Lake Agassiz Strandlines Southwest of Ashville

Figure 3.71

Vertical air photograph: A24689-108

Flight height: 26,700 feet a.s.l.; lens focal length: 152.456 mm

Date: July 3, 1977

Scale: 1:48,700 (approx.)

Location: Township 24 and 25; Ranges 20, 21, and 22 WI

Map sheets: 1:250,000 62N Duck Mountain

1:50,000 62N/1 Dauphin


3.72: Lake Agassiz Strandlines East of Duck Mountain

This photo is of an area just north of that in figure 3.71. Here the strandlines at the base of Duck Mountain (off the photo to the west) trend north/south. PTH 10 1 follows the Campbell Beach. Just to the east is another strandline followed by secondary roads 2, and further east still are a series of indefinite strandlines 3 that are both lower and newer. They can be identified on the basis of land use variations 4 and tonal variations in fields 5. In the northwest quadrant are higher, older strandlines, one of which coincides exactly with cleared woodland 6, whereas others are indicated by tonal variations in fields 7. Strandlines are often good sources of sand and gravel for road construction and other uses; two gravel pits 8 can be seen west of the Campbell Beach. Drainage is generally from west to east off Duck Mountain but in one case, Drifting River 9, its direction is profoundly influenced by strandlines. Also Broken Pipe Lake 10, which receives streams from the west 11, is backed up behind the Campbell Beach and has no obvious outlet.

The checkerboard pattern of the DLS system is clear, but there is an interesting variation in this area. Three different systems of survey were developed for use in western Canada, of these the first and third were employed in western Manitoba.[i] The first system was used south of Duck Mountain and the third covers northern areas, the boundary between the two being at the seventh correction line (i.e., the northern edge of township 26). So township 27 is the first township in the third system; it is distinctive in that it is only four sections deep—all of which are on the photo—compared with the normal six. The differences between the first and third systems are relatively minor: 1) road allowances are 66 feet in the third system compared with 99 feet in the first; 2) east/west road allowances occur along the northern edge of each section in the first system, but occur only every other section in the third system. The first difference is not visible on the photo but careful inspection shows east/west gravel roads a mile apart in some areas in township 26 12 but two miles apart in some areas in township 27 13. A small correction occurs between townships 26 and 27 resulting in a jog in PR 274 14. PR 267, an east/west road 15, follows the divide between townships 27 and 28. Finally a light-toned line in the northeast indicates the route of a power line 16.

Figure 3.72: Lake Agassiz Strandlines East of Duck Mountain

Figure 3.72: Lake Agassiz Strandlines East of Duck Mountain

Figure 3.72

Vertical air photo: A21750-34

Flight height: 25,200 feet a.s.l.; lens focal length: 88.89 mm

Date: July 27, 1970

Scale: 1:83,400 (approx.)

Location: Township 26, 27 and 28; Ranges 21 and 22 WI

Map sheets: 1:250,000 62N Duck Mountain

1:50,000 62N/1 Dauphin

62 N/8 Sifton

Notes

[i] Tyman, J. L. By Section Township and Range (Second Printing). Brandon: Brandon University, 1995, 13.



3.73: Lake Strandlines South of The Pas

Lake strandlines are widely distributed throughout central and southern Manitoba. They run along the edges of higher land that used to be the lake shoreline, the best examples being along the Manitoba Escarpment which was the western shore of Lake Agassiz. In the area shown, the “highland” was The Pas moraine which runs south from The Pas, veers east to form the land between Lake Winnipegosis to the south and Cedar Lake to the north, and continues east to form Long Point in Lake Winnipeg. On this photo higher land is to the north, and a series of east/west trending strandlines is picked out by vegetation differences 1. Those to the north are higher and older than those to the south. PTH 10 2 from Swan River (off the photo to the south) to The Pas (off the photo to the north) cuts across the strandlines. Roughly parallel to the road is a cut line 3 probably followed by a power line. This area lies within the mixed woods (coniferous/deciduous) natural vegetation region.[i] Coniferous trees (probably white spruce—Picea glauca) can be identified on the basis of their triangular shadows along PTH 10 4 and the power cut-line 5.

Figure 3.73: Lake Strandlines South of The Pas

Figure 3.73: Lake Strandlines South of The Pas

Figure 3.73

Vertical air photograph: MB95001-207

Flight height: 6,800-7,800 feet a.s.l.; lens focal length: 152.815 mm

Scale: 1:12,000 (approx.)

Date: May 13, 1995

Location: Township 51; Range 26WI

Map sheets: 1:250,000 62F The Pas

1:50,000 63F/6 No title

Notes

[i] Scott, op. cit., 1996, figure 4.2, 45.



3.74: Lake Strandlines and Spit on The Pas Moraine, South of Westray

This photograph covers an area just north of that shown in figure 3.73. The main part of The Pas moraine is located to the northeast 1. A series of Lake Agassiz strandlines appear as minor elevations 2 with slightly different vegetation than their surrounds. The waters of the lake that was in the southwest shaped a hooked spit 3 in the centre of the photo. Extending southward from the lakeward end of the spit 4 is an area of string bog 5 in which water is dark grey 6 and strings of vegetation running across the gentle slope appear in lighter tones 7. A roughly circular lake 8—partly unfilled—is located southeast of the string bog. PTH 10 9, light-toned, cuts across the northeast corner; two dark-toned vehicles 10 can be seen on the road. A cut line 11 leads south-southwest from the road; it is light-toned where it cuts across the strandlines and the spit 12 but dark-toned where it cuts across the less well-drained marshy land to the south 13. A trail 14 leads west along the spit. This area lies within the mixed woods (coniferous/deciduous) vegetation zone[i]. Coniferous trees can be identified on the basis of their triangular shadow shape best seen in a clearing in the northwest 15.

Figure 3.74: Lake Strandlines and Spit on The Pas Moraine, South of Westray

Figure 3.74: Lake Strandlines and Spit on The Pas Moraine, South of Westray

Figure 3.74

Vertical air photograph: MB95001-211

Flight height: 6,800-7,800 feet a.s.l.; lens focal length: 152.815 mm

Scale: 1:12,000 (approx.)

Date: May 13, 1995

Location: Township 51; Range 27WI

Map sheets: 1:250,000 63F The Pas

1:50,000 63F/6 Not title

Notes

[i] Scott, op. cit., 1996, figure 4.2, 45.



3.75: The Assiniboine Glacial Spillway South of Shellmouth

At the end of the Wisconsinan glaciation, melting ice produced enormous quantities of water that accumulated in massive lakes in many parts of the prairie provinces. Once a lake reached an overflow level, it spilled into lakes at lower levels, possibly in as short a time as a few months or years. The erosive power of the overflow water was great, resulting in the creation of steep-sided, flat-floored valleys—spillways—usually cut into easily eroded glacial sediments but occasionally reaching down to the underlying bedrock. Spillways of various sizes are ubiquitous throughout Alberta, Saskatchewan, and Manitoba. This photograph shows a spillway, now occupied by the Assiniboine River, which carried water from glacial Lake Assiniboine in Saskatchewan to glacial Lake Agassiz.[i] At this location just south of Shellmouth, the flat spillway floor 1 is between 0.7 and 1.0 mile (1.1 to 1.6 km) across. The steep valley walls, over 200 feet (61 m) high, can be seen to the west 2 and east 3. The dark-toned west wall is more obvious because it is completely wooded, a result of the relatively wet microclimate on the east and northeast facing slopes. The eastern wall—west facing—is drier and therefore covered by scrub. Tributary valleys, short on the west side 4 but much longer, in the form of the valley of Thunder Creek 5, in the east, dissect both sides. Thunder Creek enters the Assiniboine River 6 near the southern edge of the photo. Its valley has the characteristic v-shape of recently eroded valleys, contrasting sharply with the flat-floored spillway. The freely meandering Assiniboine occupies the spillway floor. In three places the channel impinges on and runs along the valley sides 7. Recent cutoffs can be seen at several locations 8, and at one location a whole river segment has been abandoned 9.

West of the spillway is characteristic ground moraine topography with a definite north-northeast/south-southwest orientation with long narrow sloughs in depressions 10. In the east is a drier plateau with little surface drainage except two lakes 11 and with the characteristic ripple markings of outwash 12.

The imprint of the DLS system can be seen, but in this area with two major valleys, the topography influences road directions more than is usual in southern Manitoba 13. The same is true of the CN line 14, which crosses Thunder Creek at right angles 15, then swings south on the eastern plateau 16 before running obliquely down the spillway side 17. Two prominent cuttings can be seen along the railway’s route 18.

Figure 3.75: The Assiniboine Glacial Spillway South of Shellmouth

Figure 3.75: The Assiniboine Glacial Spillway South of Shellmouth

 

Figure 3.75

Vertical air photograph: A15537-20

Flight height: 20,000 feet a.s.l.; camera focal length: 6 inches

Date: October 9, 1956

Scale: 1:35,200 (approx.)

Location: Townships 21 and 22; Ranges 29 and 30 WI

Map sheets: 1:250,000 62K Riding Mountain

1:50,000 62K/14 Inglis

62K/13 Langenburg

 

Notes

 

[i] For details see Klassen, R. W. “Wisconsin events and the Assiniboine and Q’Appelle valleys of Manitoba and Saskatchewan.” Canadian Journal of Earth Sciences, vol. 9, 1972, 544-560.

 



3.76: The Assiniboine Spillway South of Miniota

This photograph was taken from a greater height than that in figure 3.75. Hence a longer stretch—about 10 miles (16 km)—of the spillway is seen crossing the area from northwest to southeast 1. In this area the spillway is 1 to 1.25 miles (1.6 to 2.0 km) across, slightly wider where Golden Creek 2 enters from the northeast. The Assiniboine River 3 meanders freely across the spillway floor, but in one reach it hugs the south side of the valley for over two miles (3.2 km) 4. Here a dike has been built along the north bank 5 to protect the land to the north from flooding. This land is used for agriculture, and it is noticeable that three abandoned channels have dried out 6. In other places recently abandoned channels are partly water-filled 7. The valley walls are almost 250 feet (76 m) high and as in figure 3.75 the southern and western side is heavily wooded 8, whereas the south and west facing slopes have only patchy woodland 9. Two small creek valleys break the continuity of the southern side 10, while four valleys including that of Golden Creek 2 as well as Drydens Ravine 11 dissect the opposite side. The spillway is sliced across ground moraine that can be seen to the southwest and northeast. In the southwest there is a northwest/southeast lineation 12 that is missing from the northeast where the topography is very irregular with numerous intermittent lakes 13.

Most of the land on the spillway floor is used for agriculture with just a few wooded areas left 14. On either side of the spillway most land has been cleared for agriculture with some land in the process of being cleared 15. The imprint of the DLS system is obvious. Roads follow section lines except where they cross the spillway 16 and creek valleys 17. PTH 83 18 is the only major north/south route way whereas several transport lines cross the area in a general east/west direction. PTH 24 19 is very prominent and both CN 20 and CP 21 railway lines cross the area, crossing each other near the small settlement of Quadra 22. Another east/west line—light-toned on the photo—is a gas pipeline, visible because of the disturbance of the black soils during construction 23. The village of Miniota 24 is located at the junction of PTH 24 and PTH 83.

Figure 3.76: The Assiniboine Spillway South of Miniota

Figure 3.76: The Assiniboine Spillway South of Miniota

Figure 3.76

Vertical air photograph: A21748-108

Flight height: 24,700 feet a.s.l.; camera focal length: 85.611 mm

Date: July 27, 1970

Scale: 1:82,300 (approx.)

Location: Townships 12, 13, and 14; Ranges 25, 26, and 27 WI

Map sheets: 1:250,000 62K Riding Mountain

1:50,000 62K/2 Hamiota

62K/3 Miniota


3.77: The Souris Spillway South of Coulter

The photograph shows the Souris spillway just north of the Canada/U.S.A. border in southwestern Manitoba. It carried water from glacial Lake Souris to the south to glacial Lake Hind to the north.[i] As with previous examples, it has a flat floor and steep sides, but in this case they are only 50 feet (15.2 m) high. Both sides are picked out by patches of scrubby trees (1 and 2) in slightly wetter areas of this dry part of Manitoba. The Souris River 3, which has obviously been straightened, flows from south to north. A light-toned embankment 4 can be seen along the east side of the river. Several small intermittent streams 5 flow towards the main river. Land on either side of the spillway is extremely flat.

In this driest part of Manitoba, water is scarce resulting in the damming of two creeks to create reservoirs 6 and construction of two dugouts 7. Some section lines of the DLS system can be seen 8 and in the southeast is a gravel road—light-toned—constructed along one of them 9.

Figure 3.77: The Souris Spillway South of Coulter

Figure 3.77: The Souris Spillway South of Coulter

Figure 3.77

Vertical air photograph: A16181-17

Flight height: 10,500 feet a.s.l.; lens focal length: 152.63 mm

Date: July 20, 1958

Scale: 1:18,100 (approx.)

Location: Township 1; Ranges 26 and 27 WI

Map sheets: 1:250,000 62F Virden

1:50,000 62F/ 2 Waskada

Notes

[i] For details see Kehew, A. E. and Clayton, L. “Wisconsinan floods and development of the Souris-Pembina spillway system in Saskatchewan, North Dakota and Manitoba” in Glacial Lake Agassiz eds. J. T. Teller and L. Clayton. St. Johns: Geological Association of Canada, Special Paper 26, 1983, 187-209.



3.78: Souris Spillways South of Melita

In this area, just north of that shown in figure 3.77, the Souris spillway splits into a series of channels. The present-day Souris 1 occupies one of them; another to the east 2 known locally as Blind River Valley, is occupied by a small intermittent stream—Blind River 3. The higher land between the main channel and Blind River Valley 4 is known as “The Peninsula.” A similar piece of land 5 between Blind River Valley and another spillway channel 6 is “Granite Hill.” Clearly at one time water occupied all the spillway channels—probably simultaneously—but it eventually concentrated into what is now the Souris Valley, the floor of which is at a slightly lower level than the others. The main Souris spillway is steep-sided (7 and 8) and flat-floored with the river meandering freely across the floor. Several cutoffs 9 can be seen and another is imminent. Recent satellite images show that the river has now cut through this narrow meander neck 10. One cutoff 11 is peculiar in that it “faces the wrong way”—it was abandoned when the Souris flowed on the west side of the spillway rather than on the east side as it does today. The Souris is joined from the southwest by the Antler River 12 which has a more nearly v-shaped valley.

Most of the area has been cleared for agriculture with little natural vegetation remaining except patches of deciduous woodland in some meander loops on the spillway floor 13, in the Antler River Valley 14, and in bluffs on the spillway sides 15. It is noticeable that arable agriculture tends to avoid Blind River Valley; it is probably used for pasture, hence the dugouts 16 located in it. In this windy dry area of southwestern Manitoba, dugouts—small black rectangles on the photo—for water supply are ubiquitous 17, and in two locations 18, field shelterbelts planted to reduce wind erosion, can be seen. Farms, almost always with shelterbelts are distributed throughout the area 19.

Aspects of the DLS system are printed on to the landscape. The border between township 2 and 3 20 runs through the area. It is a correction line and in this western location (ranges 26 and 27) is about 1.25 miles (2 km) 21. The correction accounts for the bend in PTH 83 22. Note that the jog is only 0.25 mile 23 rather than the whole 1.25 miles. PTH 83 is joined by PTH 3 24 from the west. In the north PTH 83 veers northeast to parallel the pre-existing CP line 25.

Figure 3.78: Souris Spillways South of Melita

Figure 3.78: Souris Spillways South of Melita

Figure 3.78

Vertical air photo: A24966-09

Flight height: 16,783 feet a.s.l.; lens focal length: 85.32 mm

Date: June 28, 1978

Scale: 1:54,200 (approx.)

Location: Townships 2 and 3; Ranges 26 and 27 WI

Map sheets: 1:250,000 62F Virden

1:50,000 62F/3 Gainsborough

62F/2 Waskada


3.79: Part of the Souris-Pembina Spillway East of Souris

The Souris-Pembina spillway, which carried water from glacial Lake Hind to glacial Lake Agassiz, can be seen crossing the photo from northwest to southeast 1. It has the characteristic steep sides (2 and 3) of glacial spillways, but the floor is not as flat as usual because the Souris River 4 has migrated laterally while incising itself into the spillway floor; scars indicating previous river positions can be seen 5. At several locations the river has eroded into the underlying shales of this area 6, seen in the river cliffs on the outside of river bends; some of the eroded shale has been deposited in a point bar 7. Several small creeks 8 drain to the Souris from both the north and south. North of the spillway the topography is typical of end moraine—hummocky with sloughs in depressions 9. Much of this land is too stoney and irregular for agriculture so patches of deciduous woodland—dark-toned—remain 10. To the south the land is flat, more typical of outwash deposits.

The lines of the DLS system are seen but are obscured along the spillway course. Some gravel roads follow section lines, but both PTH 10 11 and PR 348 12 diverge from them where they cross the spillway. The boundary between townships 6 and 7 runs across the area with a correction of about 0.75 miles (1.2 km) 13 in this location. A railway line—or at least its former route 14—can be seen running obliquely across the spillway and crossing the Souris at the abandoned settlement of Bunclody 15.

Figure 3.79: Part of the Souris-Pembina Spillway East of Souris

Figure 3.79: Part of the Souris-Pembina Spillway East of Souris

Figure 3.79

Vertical air photo: A24518-21

Flight height: 26,200 feet a.s.l.; camera focal length: 153.27 mm

Date: August 6, 1976

Scale: 1:49,900 (approx.)

Location: Townships 6 and 7; Ranges 19 and 20 WI

Map sheets: 1:250,000 62F Virden

1:50,000 62F/9 Souris

62G/5 Dunrea

 


3.80: Langs Valley North of Dunrea

 

The photograph shows Langs Valley 1, a large spillway occupied by a small misfit stream 2. Langs Valley[i], delimited by the dashed lines on the photo, is part of the Souris-Pembina spillway that carried water from glacial Lake Hind to glacial Lake Agassiz. After the glacial lakes disappeared, the spillway was occupied by the Souris River that flowed eastward to join the Red River south of the Canada/U.S.A. border. However, the Souris was captured just west of the photo and redirected northward through the Tiger Hills to join the Assiniboine near Treesbank. Now a large spillway is occupied by a tiny misfit stream 2 that flows west; i.e., opposite to the original flow, to join the Souris near the elbow of capture. It has eroded a steep-sided valley into the spillway floor. The spillway’s southern wall 3 is steep and well wooded. It is dissected by two steep-sided creek valleys 4 where some slopes are too steep to support woodland. The northern valley wall 5 is not as steep and has a well-marked terrace 6 into which two small gravel pits 7 have been excavated.

This is a large-scale, low-level photo on which section lines 8 are clearly defined. Roads follow section lines with some accommodation for the topography 9. Five forms 10 can be seen in this area of 6 ¼ square miles (16.2 sq km).

Figure 3.80: Langs Valley North of Dunrea

Figure 3.80: Langs Valley North of Dunrea

Figure 3.80

Vertical air photograph: A16182-84

Flight height: 10,500 feet a.s.l.; lens focal length: 152.63 mm

Date: July 22, 1958

Scale: 1:17,600 (approx.)

Location: Township 5; Range 18 WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/5 Dunrea

Notes

[i] “Named after the Reverend James Lang who ran a popular campground in the valley in 1880” G. Holm ed. Geographical Names of Manitoba, Winnipeg: Manitoba Conservation, 2000, 143.



3.81: The Souris-Pembina Spillway South of Darlingford

The spillway can be seen trending northwest/southeast and deeply entrenched (300 feet, 91.4 m) into the surrounding landscape. It differs from spillways shown previously in that although it is steep-sided, it has a narrow floor into which the Pembina River 1 is incised. In the northwest the spillway has migrated northwards, leaving behind a wide terrace 2. Land here has been cleared for agriculture, whereas both the north side 3 and south side 4 of the spillway are covered by dark-toned deciduous woodland. The Pembina River meanders but is not freely meandering from side to side of a flat spillway floor. It is joined from the north by the Little Pembina River 5 which is also in a steep-sided, wooded valley; several minor creeks 6 join from the south. Land both north and south of the spillway is typical hummocky ground moraine topography.

This photograph shows the Canada/U.S.A. border 7 with North Dakota south of the line. Similar, but different, land division systems exist in the two countries. Many different baselines are used in the U.S.A., whereas only one—the 49th parallel—is used in Canada. The baseline used for this part of North Dakota results in only partial sections in the northern tier south of the Canadian border 8. The principal meridians used in the U.S.A. are also different from those in Canada resulting in sections in Canada being offset from those in the U.S.A. 9. This accounts for the bend on a north/south road (PTH 31 in Canada) as it crosses the border 10. In Canada roads follow section lines except where they cross the Pembina Valley (11 and 12).

Figure 3.81: The Souris-Pembina Spillway South of Darlingford

Figure 3.81: The Souris-Pembina Spillway South of Darlingford

Figure 3.81

Vertical air photograph: A21821-61

Flight height: 24,000 feet a.s.l.; lens focal length 85.55 mm

Date: August 10, 1970

Scale: 1:79,200 (approx.)

Location (in Canada): Townships 1 and 2; Ranges 7 and 8 WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/1 Morden


3.82: The Polonia Trench Northeast of Minnedosa

The area shown is on the southeastern flank of the Riding Mountain upland. The history of deglaciation of the Riding Mountain area is complicated with a series of glacial lakes forming and then emptying generally to the south and in the process creating spillways now occupied by misfit streams. Shown here is the Polonia trench 1 (bounded by dashed lines). The trench, up to 200 feet (60 m) deep, trends north-northeast/south-southwest, parallel to the Riding Mountain escarpment just off the photo to the east. The tiny Neepawa Creek 2 now occupies it. The eastern spillway wall is steep and mainly wooded 3, whereas the west wall is less steep, more dissected by tributary valleys 4, and less wooded. The spillway floor, although not absolutely flat, is flat enough to be cleared for agriculture. This has resulted in severe soil erosion, especially east of Neepawa Creek. Sediment eroded from above has been deposited in a series of small alluvial fans 5. Outside the spillway is hummocky ground moraine topography which produces marginal agricultural land so that sizeable areas are left wooded 6.

A strategically placed microwave tower 7 is located at the top of the east wall of the spillway. By careful inspection of the original photograph using a magnifying lens, both the tower (radially displaced out from the centre point of the photo) and its shadow, falling to the north-northwest, can be seen on the original photo. The shadow direction indicates that the photo was taken after noon. PR 265 8 runs through the area and the hamlet of Polonia 9. The Ukrainian Catholic Church 10 in Polonia serves a large area along the southern edge of Riding Mountain. A shrine located at the church attracts hundreds of people during an annual pilgrimage in the summer.

Figure 3.82: The Polonia Trench Northeast of Minnedosa

Figure 3.82: The Polonia Trench Northeast of Minnedosa

 

Figure 3.82

Vertical air photograph: A25800-39

Flight height: 9,900 feet a.s.l.; lens focal length: 152.034 mm

Date: July 5, 1981

Scale: 1:17,600

Location: Township 16; Range 16 WI

Map sheets: 1:250,000 62J Neepawa

1:125,000 62J/SW Neepawa

1:50,000 62J/5 Clanwilliam

 


3.83: The Dand Spillway South of Hartney

Not all spillways result from water emptying from one glacial lake to another. In some cases they were created when glacial meltwater was deflected by ice. An example is the Dand spillway—named for a hamlet just off the southwest corner of the photo. Meltwater flowed in the depression now occupied by Chain Lakes 1, a small intermittent stream 2 and two sloughs 3. The spillway, about 50 feet (15 m) below the surrounding land cuts through hummocky ground moraine. Light-toned crests 4 that result from rain splash and wind erosion on exposed soils indicate minor elevations. A minor esker-like ridge runs across the southeast corner of the photo 5.

Most of the land in the area is devoted to agriculture. Lighter-toned fields 6 have been cropped whereas darker-toned fields 7 have been left fallow. In some of the cropped fields the farmer has been cultivating the land in preparation for next year’s crop 8. Dugouts 9 are ubiquitous in this dry area of southwestern Manitoba. Gravel roads follow sections of the DLS system 10 whereas quarter sections are indicated by land use changes 11. PTH 23 12 traverses the area in the north, and at the date the photo was taken, so did the CN railway line 13 with a siding and an elevator at Underhill 14. 

Figure 3.83: The Dand Spillway South of Hartney

Figure 3.83: The Dand Spillway South of Hartney

Figure 3.83

Vertical air photograph: A20471-116

Flight height: 21,900 feet a.s.l.; lens focal length: 152.73 mm

Date: May 22, 1968

Scale: 1:41,700 (approx.)

Location: Townships 5 and 6; Range 22 WI

Map sheets: 1:250,000 62F Virden

1:50,000 62F/7 Hartney

62F/8 Elgin


3.84: Landforms of Southwestern Manitoba and Southeastern Saskatchewan

This image was obtained from Landsat I using the Multispectral Scanner (MSS) sensor, recording band 7 (0.7-0.8 mm—infrared). The sensor at a nominal altitude of 900 km (559 miles) covers a large part of southwest Manitoba and southeast Saskatchewan. At the time, December 19, 1973, most of the surface was snow covered and appears white on the image, but tree and scrub covered areas appear dark. In the north is Riding Mountain National Park 1 with a sharp boundary reflecting the difference between natural vegetation in the park and land cleared for agriculture outside it. In the south is a parkland area (woodland and grass) surrounding Oak Lake 2 and in the southeast the wooded area of Moose Mountain 3 in Saskatchewan.

At this date, close to the winter solstice, the sun is low in the sky even at noon and this image was obtained well before noon. One result is that topographic features throw prominent shadows, so that in this image spillways and meltwater channels show up prominently. This is particularly true where they trend west/east, the best example being the Qu’Appelle Valley 4. Running into the Qu’Appelle in Saskatchewan are Kaposvar Creek 5 and Cutarm Creek 6. Also trending west/east in Saskatchewan is Pipestone Creek 7. The Assiniboine spillway runs through the centre and east of the image. Prominent segments occur in the north where the Shell River enters 8, further south near Miniota 9, east of Virden 10, and near the junction with the Little Saskatchewan River 11. Entering the Assiniboine from the north are Silver Creek 12, Birdtail Creek 13, and the Little Saskatchewan River 14. The valley of the last named is prominent in its upper 15 and lower 16 reaches but almost disappears in the centre 17 although it is just as deep as to north and south. In the southeast is the Souris spillway 18—not prominent because of the sun angle—but the very small Dand spillway 19 is surprisingly obvious.

Figure 3.84: Landforms of Southwestern Manitoba and Southeastern Saskatchewan

Figure 3.84: Landforms of Southwestern Manitoba and Southeastern Saskatchewan

Figure 3.84

Landsat I Image: December 19, 1973

This image was made by recording Band 7—0.7 to 0.8 mm—(infrared)

Scale: 1:1,000,000 (approx.)


3.85: Landforms of Southwestern Manitoba

This image was obtained by one of the early land sensing satellites—Landsat I—from an altitude of about 900 km (559 miles) above the earth’s surface. Consequently a large part of southwestern Manitoba is displayed, although at a small scale of 1:1,000,000. The image was obtained on April 23, 1974 when most of the snow that had fallen during the preceding winter had melted, although some still remains on the higher land of Riding Mountain in the north 1. Some lakes within Riding Mountain National Park are still frozen and have a thin snow cover, resulting in an off-white colour; e.g. Clear Lake 2, Bottle Lake 3, Lake Audy 4, and Whitewater Lake 5. This also applies to Lake Manitoba 6, Pelican Lake 7, Rock Lake 8, and Swan Lake 9. On some other lakes the ice has at least partially melted resulting in a bluish colour, for example, Proven Lake 10, Seagull Lake 11, Oak Lake 12, and Whitewater Lake 13. Meltwater from the winter snow has accumulated in low-lying areas and produces a dark blue colour; for example along the Assiniboine spillway 14, the Souris spillway 15, and the Souris Pembina spillway between the white lakes 16. Extensive flooding is also occurring in the Jackfish Lake, Seagull Lake, and Chandler Lake area 17 as well as along the Whitemud River downstream from Westhope 18.

Of the many deltas deposited into glacial Lake Agassiz, the Assiniboine is the biggest and best documented.[i] It has its apex at Brandon 19 and fans out to the east—its boundaries are indicated by the dashed lines. On this image it is represented in buff/orange tones that represent the combined effect of radiation from vegetation—mainly parkland—with grass and tree patches—and the surficial deposits—mainly sand. Patches of coniferous trees are orange 20, resulting from the fact that they are reflecting infrared radiation that is recorded by the sensing system used. A darker patch in the northeast 21 represents an area where a late ice advance deposited till on top of the deltaic sands. The leading edge of the delta is marked by a strandline that continues to the northwest 22. A higher strandline that represents an early period of stillstand of Lake Agassiz can be seen to the west 23. To the east are numerous lower level, newer strandlines 24 left as the lake retreated to the east.

The Assiniboine has incised itself into the delta below Brandon responding to a reduced base level as Lake Agassiz retreated. Immediately below Brandon the valley floor is narrow with no room for flooding, but further east the meandering river has created a flood plain which was flooded on April 23, 1974 25. The river’s course is now near the southern edge of the delta, possibly because of greater isostatic uplift to the north where ice was thicker. Two former distributary courses can be seen; Douglas Marsh 26, Sewell Lake 27, and Epinette Creek 28 now occupy one to the north. Glenboro Marsh and the headwaters of Cypress River 29 occupy the other, to the south—dark blue because of flooding. An area with a similar colour to the Assiniboine Delta can be seen in the southwest around Oak Lake 30. Here too the colour results from a combination of vegetation and surficial deposits, silts and sands deposited into glacial Lake Hind, but without the deltaic form. Flooding—dark blue—is extensive in the low land around Oak Lake 31.

Several prominent valleys, in addition to those already mentioned, can be identified: the valleys of Birdtail Creek 32 and the Little Saskatchewan 33 spillways emanating from the Riding Mountain upland; the Polonia trench 34; the Whitemud Valley, south 35 and east 36 of Neepawa; the valley of Squirrel Creek 37, flowing from the Assiniboine delta; and the Souris Valley west 38 and north 39 of the elbow of capture 40.

Riding Mountain in the north is the most obvious upstanding landmass, but also visible in light colour are the Brandon Hills 41, part of an end moraine; the Arrow Hills, an esker 42; and the Bald Head Hills 43—also light coloured—sand dunes on the Assiniboine delta. The hummocky lake-strewn area of the Tiger Hills 44, also part of an end moraine, can be seen south of the Assiniboine delta, and less obvious near the southern edge of the image is Turtle Mountain 45, another area of end moraine indicated by a slight difference in colour from the flat land to the north.

On this image physical features are more obvious than the results of human activity except that over the whole area wherever agriculture is practised the checkerboard pattern of the DLS system is obvious.

Figure 3.85: Landforms of Southwestern Manitoba

Figure 3.85: Landforms of Southwestern Manitoba

Figure 3.85

Landsat I Image April 23, 1974

This is a colour composite of Bands 4 wavelength 0.5-0.6 mm, (green) band 5; 0.6-0.7 mm (red); and band 8 0.8-1.1 mm (infrared)

Scale: 1:1,000,000 (approx.)

Notes

[i] For details see Teller, J. T. and Clayton, L. eds. Glacial Lake Agassiz, St. Johns: Geographical Association of Canada, Special Paper 26, 1983.



3.86: The Edge of the Assiniboine Delta Near Lavenham

The lakeward edge of the Assiniboine delta, seen trending northwest southeast across the photo 1, is steep, almost fault like. Here it stands 75 feet (23 m) above the flat land—the lake floor—to the northeast. Many small streams, which probably originate at a contact between clay below and sands above, flow northeast across the delta surface 2. They dissect the delta in a dendritic pattern 3 but almost all disappear soon after crossing the delta front 4, leaving the plain without surface drainage. Dendritic drainage patterns are characteristic of stream systems etched into rocks of uniform resistance to erosion such as sand, which is the case here.

Some land on the delta surface has been cleared for agriculture 5, but most of the creek valleys are still wooded—dark-toned—as is the delta face. The trees are deciduous and a few are light-toned 6 due to the aspen leaves changing colour, indicating a fall photo. In the southwest are sand dunes 7, mostly stabilized by grasses and trees but with a few patches of bare sand 8. Similarly some land on the northeastern plain is devoted to agriculture, but a surprising amount of woodland remains. In one field stubble is being burned 9, a common practice in the fall at the date the photo was taken. Smoke can be seen drifting northwards indicating a southerly wind at the time. A dark patch 10 near the northern edge of the photo probably results from burning. As is usual in southern Manitoba, sections and quarter sections of the DLS system can be seen. Roads follow section lines with some variations due to the topography 11. The CN line 12 runs across the southern edge of the photo past the small settlement of Lavenham 13.

Figure 3.86: The Edge of the Assiniboine Delta Near Lavenham

Figure 3.86: The Edge of the Assiniboine Delta Near Lavenham

Figure 3.86

Vertical air photo: A15577-66

Flight height: 20,000 feet a.s.l.; lens focal length: 153.09 mm

Date: October 11, 1956

Scale: 1:37,300 (approx.)

Location: Townships 9 and 10; Ranges 9 and 10 WI

Map sheets: 1:250,000 62G Brandon 

1:50,000 62G/15 MacGregor


3.87: The Lake Agassiz Plain South of Roland

The plain left behind once Lake Agassiz retreated from southern Manitoba is one of the most extensive flat areas in the world. This high-level, small-scale photo covering about 133 square miles (344 sq km) gives a good impression of the plain that is almost completely flat except for an inperceptible decline to the east, towards the Red River. The slope results in a series of minor eastward flowing intermittent streams from north to south: Graham Creek 1, an unnamed creek 2, North Shannon Creek 3, Shannon Creek 4, Thornhill Coulee 5, and Deadhorse Creek 6. Several creeks have been straightened to increase the speed of flow; for example, Graham Creek 7, the unnamed tributary of North Shannon Creek 8, and Shannon Creek 9.

Until the beginning of the Twentieth Century this area was marshy and useless for agriculture until an intricate system of drainage ditches was constructed. The straightened steams are at the top of a hierarchy of drainage channels; at lower levels are hundreds of kilometres of minor channels not seen on this photo either because they are too small or because they run parallel to section lines. Although there is a limited amplitude of relief, minor depressions are wetter—and therefore darker—producing a mottled effect 10. Also two minor strandlines trending north-northwest/south-southeast can be seen 11, one of which is exploited for sand 12.

Once the soils were drained, they were excellent for arable agriculture. Consequently, apart from a few wooded, deciduous areas along creeks 13, the whole area is devoted to crop growing. Usually there are one, two, or three farms per section 14, their location being determined by the DLS system. The land is used intensively often with many fields in one section 15, in contrast with one to four per section in southwestern Manitoba. Wind is a problem in the flat area; consequently, nearly all farms have shelterbelts to north and west 16, and field shelterbelts have been planted in two locations 17. Road location is determined by the DLS system although PTH 23 18 detours around Roland 19. In this settlement roads are rather surprisingly oriented with respect to the DLS system rather than the CN railway line which passes through it 20. An abandoned line 21 enters Roland from the southeast and continues north.

Figure 3.87: The Lake Agassiz Plain South of Roland

Figure 3.87: The Lake Agassiz Plain South of Roland

Figure 3.87

Vertical air photo: A21852-12

Flight height: 24,100 feet a.s.l.; lens focal length 85.55 mm

Date: August 12, 1970

Scale: 1:81,200 (approx.)

Location: Townships 3, 4, and 5; Ranges 4 and 5 WI

Map sheets: 1:250,000 62G Brandon 

62H Winnipeg

1:50,000 62G/8 Miami

62H/5 Roland


3.88: The Red River Plain South of Sperling

This photograph is an extreme version of what is shown on figure 3.87. The only drainage channel that approaches a natural state is a small stretch of the Little Morris River in the extreme east 1, but even it is bounded by embankments on both sides. All other drainage channels are artificial and drain in straight lines down a very gentle incline from west to east. Several follow section lines, which in turn are followed by gravel roads so that the channels are not discernible on the photo. Nevertheless, topographic maps show from north to south: Forrester Drain 2 that flows into the Morris River, just off the photo to the east; an unnamed drain, which can be seen on the photo where it bends northwards near the eastern edge 3, Burnett Drain 4, which flows into the Little Morris River (off the photo); Brown Drain 5, which also flows to the Little Morris River; another unnamed drain 6, which can be seen on the photo as it is channeled between embankments (it too flows into the Little Morris River); Tobacco Creek 7, which is probably the most obvious channel on the photo as it flows between prominent embankments and into the Little Morris River in the east (small bridges cross Tobacco Creek at several section lines 8); and finally in the south Bell Drain 9 and Anderson Drain 10.[i]

This area was marshy until artificial drainage was used to reclaim it for agriculture early in the Twentieth Century. The soils developed on lake-deposited silt are uniform in texture and very fertile; consequently, virtually every acre is devoted to arable agriculture. Farming is intensive with many fields in one section 11, in contrast to the extensive agriculture with only a few fields per section in southwestern Manitoba. Farms are located mainly along section lines 12 with one or two per section. Although the land is exceedingly flat, even here minor depressions are picked out by water producing a mottled texture 13. In the southeast are some very indefinite strandlines 14.

PTH 3 15 out from Winnipeg bypasses Sperling 16 and continues west towards Carman (off the photo). The CN line 17 follows the same direction but runs through Sperling. The boundary between townships 5 and 6 18 runs across this area. This is also a municipal boundary, between the RM of Dufferin to the north and the RM of Roland to the south, and an unnamed drain follows it.

Figure 3.88: The Red River Plain South of Sperling

Figure 3.88: The Red River Plain South of Sperling

Figure 3.88

Vertical air photograph: A21668-3

Flight height: 23,400 feet a.s.l.; lens focal length 88.611 mm

Date: July 21, 1970

Scale: 1:81,200

Location: Township 5 and 6; Ranges 1, 2, and 3 WI

Map sheets: 1:250,000 62H Winnipeg

1:50,000 62H/5 Roland

Notes

[i] For details about drainage of this area see Carlyle, W. J., “Agricultural Drainage in Manitoba: the Search for Administrative Boundaries” in River Basin Management: Canadian Experiences, eds. B. Mitchell and J. S. Gardner. Waterloo: University of Waterloo, Department of Geography Publication Series, No. 20, 1983. 277-295.



3.89: Tobacco Creek Near the Western Edge of the Red River Plain

The photo shows Tobacco Creek 1 wandering eastwards across the Red River Plain. Although the creek has been straightened both west and east of the photo, it follows a natural channel here. Deciduous woodland—dark toned—grows along its course. Other channels, not wooded and only occupied in wet conditions, can be seen in two other locations 2.

Although the relief here is minimal, it is enough for rain splash and wind erosion to remove dark-coloured soil constituents from higher areas, leaving light-toned zones 3. Two minor strandlines can be seen in the east 4. Two farms are located on the most prominent strandline.

Apart from the Tobacco Creek course, virtually all the land is intensively farmed with many fields in one quarter section 5. Two farms are located close to Tobacco Creek 6—probably for water supply—and others can be seen close to section lines 7; most of these have planted shelterbelts 8. Four also have dugouts 9. Gravel roads follow section lines with a minor bend to avoid Tobacco Creek 10. The CP lines run north/south across the area at a slight angle to the DLS system 11.

Figure 3.89: Tobacco Creek Near the Western Edge of the Red River Plain

Figure 3.89: Tobacco Creek Near the Western Edge of the Red River Plain

Figure 3.89

Vertical air photograph: A16183-14

Flight height: 10,500 feet a.s.l.; lens focal length 152.63 mm

Date: July 22, 1958

Scale: 1:18,900 (approx.)

Location: Township 5; Range 4 WI

Map sheets: 1:250,000 62 H Winnipeg

1:50,000 62H/5 Roland


3.90: Relict Ice Scour Features Near St. Laurent

In this flat area numerous intersecting lineations, trending in several directions, can be seen. Many are straight 1, but a few have a definite curve 2. Without the benefit of stereovision it is hard to tell whether they are negative or positive features. However, the fact that they are mainly dark-toned 3 due to high soil moisture content suggests that they are furrows. Also, in many cases the availability of water results in tree growth—dark-toned 4. These are minor relief features only a meter (3 ft) or so in depth, and it is suggested that they were scraped into the bottom of Lake Agassiz by the submerged parts of icebergs which must have been driven by winds from several different directions.

PTH 6 5 crosses the southwest corner with another road joining it from the east 6. The CN railway line 7 is north of, and parallel to, PTH 6. A minor track can be seen in the north 8. Several linear features defy explanation: some southwest/northeast trending lines demarcate areas of different tone 9; also a square feature may be a partially cut field of hay 10.

Figure 3.90: Relict Ice Scour Features Near St. Laurent

Figure 3.90: Relict Ice Scour Features Near St. Laurent

 

Figure 3.90

Vertical air photograph: A17529-208

Flight height: 8,800 feet a.s.l.; lens focal length: 153.04 mm

Scale 1:16,000 (approx.)

Date: July 27, 1961

Location: Township 17; Range 4WI

Map sheets: 1:250,000 62I Selkirk

1:50,000 62I/5 St. Laurent

 


3.91: Palaeochannels of the Assiniboine River East of Portage la Prairie

At Portage la Prairie the Assiniboine River emerges from a confined valley onto the flat floor of glacial Lake Agassiz. As a result of the lack of confinement and the decrease in gradient, an alluvial fan with a radius of 30-45 kilometres has been deposited. It was constructed by numerous palaeochannels of the Assiniboine River as the lake level declined beginning about 9500 years ago. The palaeochannels “are similar in size and geometry to the modern Assiniboine, a perennial, meandering suspended load river.”[i]

This photograph shows the Assiniboine River 1 and five of the palaeochannels, from north to south: High Bluff 2, Mill Creek 3, La Salle 4, West Branch La Salle 5, and Elm River 6. The meandering Assiniboine has left behind two cutoffs 7 that appear natural and two others 8 that appear artificial; the Norquay Provincial Recreational Area is located within the southernmost of the two 9. Meander scrolls left by the meandering palaeochannels can be seen in several locations 10. The evolution of the fan involved the Assiniboine repeatedly changing its position as a result of breaking levees during floods, possibly as a result of ice jams.[ii] The markings 11 were probably created by water rushing through a gap in a levee.

Most of the land in this area is intensively farmed and irrigation is practised using water extracted from buried palaeochannels.[iii] Land division varies from that seen on previous photos in that near the Assiniboine, division is according to the long lot system with narrow fields running back from the river 12. Further south the DLS system is used with sections and quarter sections being divided into small fields in this rich agricultural region 13. Common crops in this area are potatoes and vegetables grown under irrigation.

The most prominent routeway is the twinned Trans-Canada Highway 14. South of it PR 331 15 runs through Oakville 16 that also has the CN line near its southern edge 17. North of the Assiniboine, PTH 26 18 runs through Poplar Point 19, and the CP line 20 runs just north of that. A large Hutterite colony is visible in the west 21.

Figure 3.91: Palaeochannels of the Assiniboine River East of Portage la Prairie

Figure 3.91: Palaeochannels of the Assiniboine River East of Portage la Prairie

Figure 3.91

Vertical air photograph: A21852-19

Flight height: 24,100 feet a.s.l.; lens focal length: 85.55 mm

Date: August 12, 1970

Scale: 1:82,300 (approx.)

Location: Townships 11 and 12; Ranges 2, 3, 4, and 5 W1

Map sheets: 1:250,000 62G Brandon

62H Winnipeg

62I Selkirk

62J Neepawa

1:50,000 62G/16 Portage la Prairie

62H/13 Elie

62I/4 Warren

62J/1 MacDonald

Notes

[i] Rannie, W. F. “The Portage la Prairie ‘Floodplain Fan’.” in Alluvial Fans: A Field Approach, eds. A.H. Rachocki and M. Church, Chichester, England: John Wiley and Sons, 1990, 179.

[ii] For a detailed description of the origin see Rannie, W. F., Thorleifson, L. H. and Teller, J. T. “Holocene evolution of the Assiniboine River palaeochannels and Portage la Prairie alluvial fan.” Canadian Journal of Earth Sciences, vol. 26, 1989, 1834-1841.

[iii] Sawatsky, T. “Irrigation in the Central Manitoba Irrigation Association Region” in Irrigation in Manitoba: Past, Present and Future ed. J. Welsted. Brandon: Canadian Water Resources Association, 1998, 14-19.



3.92: The Assiniboine River, the La Salle River, and the Elm River Palaeochannels East of Portage la Prairie

This larger scale photograph shows more detail of the Assiniboine River and of two palaeochannels than figure 3.91. The Assiniboine River 1 meanders across the centre of the area leaving behind three natural cutoffs 2. There are three other cutoffs 3 which appear artificial. In this area the Assiniboine flows between levees on both north 4 and south 5 sides. These are partly natural but have been heightened to protect agricultural land from flooding. A dike has been built south of the river 6 for the same purpose. Meander scrolls left by the shifting river can be seen north 7 and south 8 of the present channel. The Elm River palaeochannel 9 is visible in the south. It too has left prominent meander scrolls 10, and judging from their configuration at 11, it looks as if the waters of the Elm River palaeochannel once emptied into the headwaters of the La Salle palaeochannel at 12. It is noticeable that although the upper parts of the palaeochannels meander, the lower parts of both Elm River 13 and La Salle River 14 do not. Rannie[i] found that lateral migration occurred where the channels formed in relatively course-grained materials, but further east where the channels are bounded by lacustrine clay “lateral activity is inhibited or absent”.

Near the Assiniboine River, most noticeably to the north, the land is divided into long fields running back from the river 15, using the long lot system, whereas in the south the DLS system of squares is in evidence. The boundary between townships 10 and 11 runs across the area with a quarter mile (0.4 km) correction at the junction 16.

Agriculture in the area is intensive, frequently aided by irrigation with water from either the Assiniboine or from buried palaeochannels. This is most noticeable north of the Assiniboine River 17 where many small fields can be seen, probably supporting vegetables and fruits. The Portage area is the main strawberry growing region of Manitoba,[ii] and it seems likely that strawberries are grown in some of the fields close to the river. Similar intensive growing areas are located in Hoop and Holler Bend 18 and along the Elm River 19.

The twinned Trans-Canada Highway 20 can be seen in the north; it veers off to the south to bypass Portage la Prairie which is just off the photo to the west. PTH 26 21 is north of the Trans-Canada Highway and the CP railway line 22. Between the highway and railway are faint indications of the High Bluff palaeochannel 23. The CN line 24 trends west-northwest/east-southeast crossing the Assiniboine River in the process 25. In the west a road out from Portage la Prairie 26 approaches the Assiniboine River. There is no bridge, but the trend continues south of the river 27. In the extreme southwest are the ends of runways 28 at the Southport airbase (CFB Portage la Prairie). Two Hutterite colonies can be seen, the Elm River Colony 29 and another in the extreme southeast 30.

Figure 3.92: The Assiniboine River, the La Salle River, and the Elm River Palaeochannels East of Portage la Prairie

Figure 3.92: The Assiniboine River, the La Salle River, and the Elm River Palaeochannels East of Portage la Prairie

Figure 3.92

Vertical air photograph: MB89021-6-176

Flight height: 30,800 feet a.s.l.; lens focal length: 152.26 mm

Date: August 7, 1989

Scale: 1:57,600 (approx.)

Location: Townships 10, 11, 12; Ranges 5 and 6 WI

Map sheets: 1:250,000 62G Brandon 

1:50,000 62G/16 Portage la Prairie

Notes

[i] Rannie, op. cit., 1990, 183.

[ii] Portage la Prairie claims to be the strawberry capital of Canada and has a strawberry festival each year.



3.93: Raised Strandlines, West Shore of Hudson Bay, South of Cape Churchill

The image shows part of the west shore of Hudson Bay 1 with Thompson Point 2 near the south edge. Uplift since the end of the Ice Age has resulted in a series of strandlines indicating former shore positions. On this image they range up to about 100 feet (30.5 m) above sea level and appear as light-toned linear, north/south trending features 3. Those in the west 4 are higher and older than those further east 5. The light tone indicates sand and gravel at the surface. Near the present shoreline, the strandlines are less distinct 6 and are probably covered by tundra vegetation as this area lies within the shrub-tundra vegetation zone[i].

Inland the land is covered by shrub tundra 7 and there are several large lakes—dark blue in colour and therefore probably deep and without suspended sediment. The largest are Napper Lake 8, Hannah Lake 9, and Mary Lake 10. Light-blue lakes, probably shallower and with suspended sediment, can be seen behind 11 and between 12 the strandlines. The course of the White Whale River 13, which drains through a dark blue lake 14 and eventually to Hudson Bay can be observed in the north.

Figure 3.93: Raised Strandlines, West Shore of Hudson Bay, South of Cape Churchill

Figure 3.93: Raised Strandlines, West Shore of Hudson Bay, South of Cape Churchill

Figure 3.93

Google Earth 2005: Image 2006 Terra Metrics

Scale: 1:193,000 (approx.)

Location of Thompson Point: 58º 18'N, 92º 59'W

Map sheets: 1:250,000 54K Churchill

Notes

[i] Scott, op. cit. 1996, figure 4.2, 45.



3.94: Raised Strandlines on the Hudson Bay Coast South of Cape Churchill

The weight of ice that covered Manitoba during the Pleistocene “caused depression of the earth’s crust which rebounded towards its former position once the ice melted. Depression and subsequent rebound was greatest where the ice was thickest. In Manitoba the Hudson Bay lowlands were depressed relative to sea level, resulting in transgression of the sea (called the Tyrrell Sea) as far inland as 200 km from the present shore of Hudson Bay. Strandlines formed along the shore and have since been elevated to heights as much as 183 m on the Manitoba-Northwest Territories [Nunavut] border.”[i]

In this photograph of an area about 15 miles (24 km) south of Cape Churchill, a series of strandlines can be seen running roughly parallel to the coast of Hudson Bay 1. The most prominent strandlines are the highest 2, suggesting that the sea stood at this level for an extended period. Below them are less continuous strandlines 3 formed as the sea retreated in stages. Many lakes exist in the lower land between strandlines. These vary in tone from very dark grey 4 to almost white 5, depending on the lake surface/sun angle/camera angle relationship (the specular reflection effect). The White Whale River reaches the sea in this area 6. Part of its course can be traced back from the coast 7, but further inland it is difficult to follow. Inland from the strandlines is flatland covered by shrub-tundra, although around Klohn Lake 8 in the southwest the dark tone suggests more shrubs 9. This area in which drainage is to the north also includes numerous lakes in various tones 10.

Figure 3.94: Raised Strandlines on the Hudson Bay Coast South of Cape Churchill

Figure 3.94: Raised Strandlines on the Hudson Bay Coast South of Cape Churchill

Figure 3.94

Vertical air photograph: A17406-66

Flight height: 30,000 feet a.s.l.; lens focal length: 88.28 mm

Date: July 31, 1961

Scale: 1: 101,000 (approx.)

Location of the mouth of White Whale River: 58 34'N, 93° 08'W

Map sheets: 1:250,000 54K Cape Churchill

Notes

[i] Corkery, M. T. “Geology and Landforms of Manitoba” in Welsted, Everitt, & Stadel eds. op. cit., 18.



3.95: Raised Strandlines North of the Lower Churchill River

At this location, about 45 miles (72 km) from its mouth, the Churchill River 1 is still almost 200 feet (61 m) above sea level. The river flows in a remarkably straight steep-sided channel about 0.4 kilometres (1,312 feet) wide with rapids along its course 2.[i] North of the Churchill is a prominent arcuate strandline 3 that is almost 400 feet (122 m) above present sea level. The north end of the strandline 4 is light-toned, suggesting sand or gravel at the surface, whereas in the south there are several distinct ridges, darker in tone 5, possibly covered by vegetation. To the west—further inland and at a higher elevation—are several other minor strandlines 6. The Churchill receives a left bank tributary, Chasm Creek 7, near the southern edge of the photo. Further north, Robson Creek 8 flows to the east, its direction in one stretch being determined by the major strandline 9. Another river further north is also deflected by the strandline, in this case to the north 10. Several straight river segments 11 and angular bends 12 suggest some structural control of the drainage.

This area is located within the open lichen woodland vegetation area of Manitoba; the lichens account for the light-toned areas 13 whereas the darker areas especially in the southwest 14 are tree covered. Many dark-toned lakes 15 dot the surface, but in the southeast specular reflection produces light tones 16.

Figure 3.95: Raised Strandlines North of the Lower Churchill River

Figure 3.95: Raised Strandlines North of the Lower Churchill River

Figure 3.95

Vertical air photograph: A17406-8

Flight height: 30,000 feet a.s.l.; lens focal length: 88.28 mm

Date: July 31, 1961

Scale: 1:100,000 (approx.)

Location of centre point: 58° 05'N, 94° 58'W

Map sheets: 1:250,000 54 L Churchill

1:50,000 54L/2 Red Head Rapids

Notes

[i] This photograph was taken before the diversion of a large proportion of the flow of the Churchill River into the Nelson River to increase the flow of the latter for HEP generation. The Churchill now probably occupies only a proportion of the channel shown in the photo.



3.96: The Bald Head Hills South of Carberry

 

The main requirement for sand dunes to form is a plentiful supply of sand which can be transported and subsequently deposited by the wind. In southern Manitoba this requirement is met principally where sediments were deposited into glacial lakes, particularly lakes Agassiz and Hind, which retreated or dried out leaving deposits open to wind action. Dunes are also found on some glacial outwash deposits and along the shores of some major lakes.

 

The largest area of dunes in Manitoba is located on sands which are part of the Assiniboine Delta deposited into the west side of Lake Agassiz: “The main area of contiguous uninterrupted dunes (both stabilized and active) is estimated at 960 km2.” It is fourth largest such region in Canada.[i] Sand deposits are up to 70 metres thick. “As the lake drained, the sediments were exposed and reworked by wind into landforms ranging from low mounds and hills to true dunes. The most common type is the parabolic dune, often quite elongated. These may be grouped into large complexes, appearing as a series of “waves” or “chains.”[ii]

The photograph shows a group of active dunes known as the Bald Head Hills. Bare sand is almost white on the photograph. The dune waves have a gentle upwind side (to the northwest) and a steep lee face (to the southeast). Tracing the dunes from the southeast, at least seven faces 1 can be seen with steep slopes at the angle of repose of the component sands (about 35°). On the gentle windward slopes, ripple marks can be identified especially on the first three dunes, counting from the southeast 2; and at the back of each slope, vegetation (grasses and trees) is growing in the lowland between dunes 3. The dunes are moving slowly to the southeast in response to the prevailing northwest winds, in some cases burying trees in the process.

Another dune complex can be seen further north 4. Here there is less bare sand, although some is seen near the southeastern edge 5. The area is mainly grass-covered, but all this area was active in 1928. Also recent photographs and personal observation reveal there is much less bare sand in the southern dune complex than there was at the time of the photo.[iii] In addition to the two dune complexes, there are two dune ridges 6 both of which are now stabilized by grass and trees.

This area lies in a region where three major North American vegetation formations overlap: the Grassland (or “prairie”), the Boreal (northern coniferous) Forest, and the Temperate (eastern) Deciduous Forest. On the photograph grassland can be seen in the southwest. It has a light grey tone and smooth texture 7. It surrounds patches of deciduous trees; mainly aspen (Populus tremuloides) that have almost the same tone, but a mottled texture 8. West of both dune complexes are stands of dark-toned coniferous trees mainly white spruce (Picea glauca) 9. Isolated coniferous trees, identified on the basis of their dark tone and triangular shadow shape, can be seen on the plain behind the dune complexes 10. It is noticeable that on the dune ridges, trees—mainly coniferous—cover the north facing slopes 11, whereas the south-facing slopes are bare or grass covered 12, a reflection of a drier microclimate on the south-facing slopes.

The white line in the east 13 is a path that was probably originally a fireguard but is now used for visitor access. The Bald Head Hills are now part of the Spruce Woods Provincial Park. They attract numerous visitors to the “Manitoba Desert”.[iv]

Figure 3.96: The Bald Head Hills South of Carberry

Figure 3.96: The Bald Head Hills South of Carberry

Figure 3.96

Vertical air photograph: A16405-16

Flight height: 10,500 feet a.s.l.; lens focal length: 152.63 mm

Date: October 19, 1958

Scale: 1:18,600 (approx.)

Location: Township 8; Range 14 WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/11 Glenboro

Notes

[i] Rogosin, op. cit., 1996, 56.

[ii] Rogosin, op. cit., 1996, 56.

[iii] “Of the original 6,500 square kilometers of deltaic sand, only 4 square kilometers remain open” Guide to Spruce Woods Provincial Park. Winnipeg: Manitoba Natural Resources, 1998.

[iv] The area of open sands is also referred to as The Spirit Sands or the Manitoba Desert.



3.97: Epinette Creek and Sand Dunes East of Shilo

In the western half of this panchromatic photo are two dune complexes 1 2; the northern one is completely stabilized, but the southern one is less so. The latter shows areas of very light-toned bare sand 3, but it is mostly grass-covered (light grey) 4 with an area of dark-toned coniferous trees, probably white spruce (Picea glauca), to the west 5. The northern complex is mainly grass-covered 6 with patches of deciduous trees, probably aspen (Populus tremuloides) 7, and isolated white spruce (Picea glauca) 8 identified by their dark tone and triangular shadow shape. Dune ridges bound the dune complexes 9, 10, 11. The central of the three shows an interesting variation in vegetation cover: the south side, with a dry microclimate, is bare or grass covered 12; the north, wetter side, is grass or tree-covered 13. A similar arrangement is seen on the northern ridge 11. Other indefinite stabilized dune ridges occur in the northwest 14.

East of the dunes Epinette Creek 15 occupies a dark-toned area 16—the path of a former distributary of the Assiniboine River across its delta. The creek flows southeastward to join the Assiniboine River off the photo. The trees in this area are mainly tamarack (Larix laricina) that can exist in wet conditions, but east of the creek 17 are stands of light-toned trees, probably deciduous trees that have changed colour on this fall photo.

In the northeast is a small patch of agricultural land 18. The CN line crosses the area in the north 19, and a light-toned path 20 can be seen in the east. This is probably used only by military vehicles as the area lies within the Shilo range and training area. A circular depressed area 21 east of the northern dune complex defies easy explanation. Less clearly defined circular features occur further south 22.

Figure 3.97: Epinette Creek and Sand Dunes East of Shilo

Figure 3.97: Epinette Creek and Sand Dunes East of Shilo

 

Figure 3.97

Vertical air photograph: A23692-116

Flight height: 13,700 feet a.s.l.; lens focal length: 153.22 mm

Date: May 12, 1974

Scale: 1:25,000 (approx.)

Location: Townships 9 and 10; Range 15 WI

Map sheets: 1:250,000 62G Brandon 

1:50,000 62 G/14 Carberry

 


3.98: Epinette Creek and Sand Dunes East of Shilo: Colour Infrared Photo

This photograph illustrates the usefulness of infrared photographs in identifying vegetation. On infrared photographs,[i] vegetation that is photosynthesizing reflects large amounts of infrared radiation and is imaged as red. On this fall photo, only coniferous trees are growing. These are therefore easily identified on the basis of their red/orange colour and triangular shadow shape.

On the southern dune complex, there are patches of almost white 1 on bare sand; grasses are dark green 2, and coniferous trees—white spruce (Picea glauca)—are orange/red 3. On the northern complex white spruce can be seen in the southeast 4; most of the rest is covered by grasses 5 and dark green patches of deciduous trees 6. The deciduous trees throw short shadows making it possible to differentiate them from grasses. Coniferous trees also occur along the dune ridges (7 and 8).

The vegetation on either side of Epinette Creek is dull green (9 and 10). The colour and the mottled texture suggest a tree cover, probably tamarack (Larix laricina) that enjoys wet conditions. There are also patches of other coniferous trees 11, in this case damp-tolerant black spruce (Picea mariana). East of Epinette Creek, a light-toned area with mottled texture and rounded shadow shapes 12 is probably an aspen (Populus tremuloides) covered area.

Figure 3.98: Epinette Creek and Sand Dunes East of Shilo: Colour Infrared Photo

Figure 3.98: Epinette Creek and Sand Dunes East of Shilo: Colour Infrared Photo

 

Figure 3.98

Vertical air photo (colour infrared): A37130 IR 5870

Flight height: 11,000 feet a.s.l.; lens focal length: 153.12 mm

Date: October 29, 1974

Scale: 1:21,600 (approx.)

Location: Townships 9 and 10; Range 15 WI

Map sheets: 1:250,000 62G Brandon 

1:50,000 62 G/14 Carberry

 

Notes

[i] The surface of this old photo is starting to deteriorate which might result in some vertical lines appearing on the screen.


 


3.99: Stabilized Dunes on the Assiniboine Delta Northwest of Holland

 

With the exception of two small areas in the northwest and southeast, virtually the whole area is covered by sand dunes developed on the Assiniboine Delta. In the northeast is a meander of the Assiniboine 1, with scars left at previous positions of the river 2. In the southeast is the Cypress River 3 deeply incised into the delta. Three steep-sided tributary valleys 4, 5, 6, join it. The only land cleared for agriculture is south of the Cypress River 7.

Virtually all the dunes are stabilized, with the exception of a patch of bare sand in the west 8. This dune complex has a steep, wooded northeastern slope 9. Several dune ridges can be seen 10 with a general west-northwest/east-southeast trend in response to the prevailing wind. The stabilized dunes are covered by: 1) grasses that are light toned with smooth texture 11; 2) deciduous trees, probably aspen (Populus tremuloides) 12 that are darker toned and have a mottled texture; and 3) patches of, and individual, coniferous trees, probably white spruce (Picea glauca) 13 that are dark-toned with a triangular shadow.

The Assiniboine Valley side and the Cypress Valley and tributary valleys are wooded. This is probably riverine gallery forest “dominated by cottonwood, Manitoba maple, green ash and willows.”[i] South of the Assiniboine are light-toned patches of trees 14, probably deciduous trees that had changed colour by the time this fall photo was taken. A dark-toned area north of the Cypress River 15 is marshy and probably covered by willow (Salix spp.) trees.

Figure 3.99: Stabilized Dunes on the Assiniboine Delta Northwest of Holland

Figure 3.99: Stabilized Dunes on the Assiniboine Delta Northwest of Holland

Figure 3.99

Vertical air photograph: A15577-15

Flight height: 20,000 feet a.s.l.; lens focal length: 153.09 mm

Date: October 11, 1956

Scale: 1:39,750 (approx.)

Location: Townships 7 and 8; Range 12 WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/10 Treherne

62G/11 Glenboro

Notes

[i] Scott, op. cit., 1996, 46.



3.100: Stabilized Parabolic Dunes on the Assiniboine Delta South of Lavenham

This area is close to the lakeward edge of the Assiniboine delta and was probably uncovered by water at an early stage. Five well-developed parabolic dunes can be seen 1. Parabolic dunes have arms that point upwind—to the northwest in this case—and steep, rounded leeside slopes to the southeast. Grasses on the windward slopes 2 and trees on the leeward slopes 3 have long since stabilized the dunes.

Away from the steeper slopes the vegetation is mainly deciduous woodland 4—identified by rounded shadow shapes—with low bushes between 5. Some land has been cleared for agriculture; the sandy nature of the soils is indicated by the mottled tones in the fields 6. The Assiniboine River 7 flows to the east across the southeast corner with riverine gallery forest along its banks 8. Meander scrolls can be seen in the agricultural land south of the river 9.

A gravel road 10 crosses the south, and paths can be seen in the woodland, several congregating at one point 11 suggesting that something is either assembled at or distributed from this point. The cut line 12 marks a section boundary.

Figure 3.100: Stabilized Parabolic Dunes on the Assiniboine Delta South of Lavenham

Figure 3.100: Stabilized Parabolic Dunes on the Assiniboine Delta South of Lavenham

Figure 3.100

Vertical air photograph: A16574-61

Flight height: 9,000 feet a.s.l.; lens focal length: 152.34 mm

Date: June 19, 1959

Scale 1:15,400 (approx.)

Location: Township 9; Range 10 WI

Map sheets: 1:250,000 62G Brandon 

1:50,000 62G/10 Treherne


3.101: Part of the Lauder Sand Hills Northwest of Lauder

Sand deposited into Lake Hind in southwestern Manitoba was exposed to wind action when the lake retreated. Sand dunes have been formed in this area north of the Souris River 1 that flows to the east across the southern edge. The dunes are mainly northwest/southeast trending ridges in response to the prevailing winds. Most are stabilized, but bare sand can be seen at several locations 2. The vegetation cover consists of grasses—light-toned with smooth texture 3—and deciduous woodland, which is darker-toned with mottled texture 4. A marked vegetation difference exists on either side of the dune ridges. The south side with a dry microclimate is either bare or grass covered 5, whereas the wetter north-facing side is wooded 6. A few patches of land have been cleared for agriculture, the sandy nature of the soil being indicated by light tones 7. The Souris River meanders across the southern edge. Steep river cliffs, sometimes cut into dunes 8, occur on the outside of bends, and light-toned point bars appear on the inside 9. Meander scrolls are also visible on the insides of meander loops 10. Two old cutoffs 11, and one more recent 12 can be seen.

Land south of the river has been cleared for agriculture; the results of harvesting can be seen in one field 13 with rectangular straw stacks 14 and a pile of loose straw 15. Farm buildings are visible at 16.

Figure 3.101: Part of the Lauder Sand Hills Northwest of Lauder

Figure 3.101: Part of the Lauder Sand Hills Northwest of Lauder

Figure 3.101

Vertical air photograph: A16410-112

Flight height: 10,500 feet a.s.l.; lens focal length: 152.63 mm

Date: October 28, 1958

Scale: 1:17,500 (approx.)

Location: Townships 5 and 6; Ranges 24 and 25 WI

Map sheets: 1:250,000 62F Virden

1:50,000 62F/7 Hartney


3.102: The Hudson Bay Coast Southeast of Cape Merry at the Mouth of the Churchill River

In the south is the rocky shore of Hudson Bay with fracture and joint zones in the Precambrian bedrock 1. Sand and gravel have been deposited to form beaches in shallow bays (2 and 3). In the case of the western beach, runnels that carry water back to the sea at low tides are obvious 4. Offshore, wave crests can be seen in deeper water 5. As waves approach shallow water they begin to break, indicated by white areas along wave crests 6. Swash (up beach movement of water) and backwash (down beach movement) can be seen at a number of locations 7. It is noticeable that breaking waves are absent where deep water comes up against a headland 8. A light-toned line well out to sea 9 probably represents the advancing tide.

The outskirts of Churchill 10 and an associated road 11 can be seen in the southwest and southeast respectively.

Figure 3.102: The Hudson Bay Coast Southeast of Cape Merry at the Mouth of the Churchill River

Figure 3.102: The Hudson Bay Coast Southeast of Cape Merry at the Mouth of the Churchill River

Figure 3.102

Vertical air photograph: A16776-48

Flight height: 5000 feet a.s.l.; lens focal length: 152.38 mm

Date: September 4, 1959

Scale: 1:10,000 (approx.)

Location of headland at 8:58° 46'N, 94° 08'W

Map sheets: 1:250,000 54L Churchill

1:50,000 54L/16 Churchill


3.103: Coastal Features on the West Shore of Lake Winnipeg

Several of the landforms usually associated with seacoasts are located along the shores of the large lakes of Manitoba. Shown here is part of the west shore of Lake Winnipeg south of Gimli. Just off the photo to the northeast is Willow Point, a cuspate foreland, the southwestern edge of which can be seen in the form of sand bars 1. Behind these are a lagoon 2 fringed by dark-toned marshes 3. To the south the shore is backed by sand dunes 4 with a series of sand bars (some above and some below water) 5 parallel to the shore. Two small streams, Willow Creek in the north 6 and a small, unnamed creek 7 in the south, flow into the lake.

Inland, PTH 9 8 and the CN railway 9 line run roughly parallel to the coast. The small community of Husavik is seen in the south 10.

Figure 3.103: Coastal Features on the West Shore of Lake Winnipeg

Figure 3.103: Coastal Features on the West Shore of Lake Winnipeg

Figure 3.103

Vertical air photo: A17333-79

Flight height: 8,550 feet a.s.l.; lens focal length: 153.04 mm

Scale: 1:16,300 (approx.)

Date: August 5, 1961

Location: Townships 18 and 19; Range 4 E

Map sheets: 1:250,000 62I Selkirk

1:50,000 62 I/10 Victoria Beach


3.104: Willow Point, West Shore of Lake Winnipeg

Willow Point 1 is a cuspate foreland projecting into Lake Winnipeg 2. A spit 3 growing southward has tied an island 4 to the mainland. Faint parallel lines on the southwest side of the island 5 may indicate former higher levels of Lake Winnipeg. A sand bar 6 hooked at its distal end 7 projects southwest from the island. A sandy beach—light-toned—8 runs the whole length of the spit with some dune development inland 9. Patterns of waves approaching the spit 10 indicate that there are beach cusps when water in the lake is lower. Further out in the lake wave fronts trend generally east/west 11: waves approach the northwest/southeast trending shore of the spit at an angle, which explains the southeastward drift of sand. Behind the spit, the “island”, and the sand bar are marshy areas 12, some with a distinctive circular shape 13.

A road runs the whole length of the spit 14 and the length of the sand bar 15.

Figure 3.104: Willow Point, West Shore of Lake Winnipeg

Figure 3.104: Willow Point, West Shore of Lake Winnipeg

Figure 3.104

Vertical air photograph: A17333-83

Flight height: 8,550 feet a.s.l.; lens focal length: 153.04 mm

Scale: 1:15,000 (approx.)

Date: August 5, 1961

Location: Townships 18 and 19; Range 4E

Map sheets: 1:250,000 62I Selkirk

1:50,000 62I/10 Victoria Beach


3.105: Spits at Gull Bay, South of Long Point, West Side of Lake Winnipeg

The image shows two spits growing across Gull Bay 1, logically named North Bar 2 and South Bar 3. There is also a spit-like feature 4 growing southward from the south end of South Bar entrapping a lagoon 5 behind it. The general drift of sediment seems to be from north to south that would explain North Bar and the spit south of South Bar. Sediment is probably derived by erosion of Long Point—an end moraine—the western end of which is visible on the image 6. South Bar is created by a secondary anticlockwise swirl within Gull Bay resulting in northward growth of the spit. Two small streams, North Twin Creek 7 and South Twin Creek 8, are deflected southward by sediment deposited across their mouths 9. Sedimentation behind North Bar results in a different colour 10; in the future marsh will grow in this area. Inland, strandlines indicating higher lake levels can be seen 11. These are followed by a road 12 connecting the shore with PTH 6 13 that leads north to Grand Rapids and south to Fairford. Paralleling the southern part of the highway are wide, cleared areas 14 that are the route followed by power lines south to Winnipeg from the hydro power station at Grand Rapids.

Figure 3.105: Spits at Gull Bay, South of Long Point, West Side of Lake Winnipeg

Figure 3.105: Spits at Gull Bay, South of Long Point, West Side of Lake Winnipeg

Figure 3.105

Image from Google Earth 2005: Image 2006 Terra Metrics

Scale: 1:126,000 (approx.)

Location: Townships 44, 45, 46; Ranges 10 and 11WI

Map sheets: 1:250,000 63B Waterhen Lake


3.106: Raised Spit, West Shore of Lake Winnipeg, North of Gimli

The land shown here is on the west shore of Lake Winnipeg 1, extending from Silver Harbour 2 in the north to Camp Morton 3 in the south. Inland is the Interlake Region in which the land is divided according to the DLS system with roads running along both north/south 4 and east/west 5 section lines. The pattern is broken, however, by a road trending generally northwest/southeast 6 that follows a linear landform 7. This is interpreted as a spit deposited when Lake Winnipeg was at a higher level. The south end is wider 8 and light-toned suggesting that it is exploited for sand and gravel. Faint lines with the same orientation as the spit are seen in wooded land further east 9. These are strandlines, at a lower level and therefore newer than the spit, deposited as the lake fell.

This is an important recreational area for Winnipeg with extensive cottage developments along the lake shore at: Silver Harbour 2, Spruce Bay Heights 10, Spruce Sands 11, Glen Bay 12, and Camp Morton 3. Rather surprisingly two main roads— PTH 8 13 and 9 14—only one section apart, run north/south; PTH 8 continues north to Hecla.

Figure 3.106: Raised Spit, West Shore of Lake Winnipeg, North of Gimli

Figure 3.106: Raised Spit, West Shore of Lake Winnipeg, North of Gimli

Figure 3.106

Image obtained from Google Earth: Image 2006 Terra Metrics

Scale: 1:100,000 (approx.)

Location: Townships 20 and 21; Range 4E

Map sheets: 1:250,000 62I Selkirk

1:50,000 62I/


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