Surficial Geology of the Swan Lake Map Sheet (NTS 63C), Manitoba
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Island 102° R 29 W R 28 W R 27 W R 26 W R 25 W R 24 W R 23 W R 22 W R 21 W R 20 W R 19 W R 18 W 100° 300 000 325 000 350 000 375 000 400 000 Channel 425 000 Island 53° 53° 0 SURFICIAL GEOLOGY COMPILATION MAP SERIES 0 0 5 Red 7 Cameron 8 The Surficial Geology Compilation Map Series (SGCMS) addresses an increasing demand for 5 D Dawson Bay e ! consistent surficial geology information for applications such as groundwater protection, Tp 46 er R Tp 46 ive 10 r YZ Bay LAKE industrial mineral management, protected lands, basic research, mineral exploration, Red Deer engineering, and environmental assessment. The SGCMS will provide province-wide coverage Dawson at scales of 1:500 000, 1:250 000 and a final compilation at 1:1 000 000. The unit polygons were digitized from paper maps originally published by the Geological Lake Survey of Canada and Manitoba Geological Survey (MGS). In several areas, digital polygons derived from soils mapping were used to fill gaps in the geological mapping. The 1:250 000 scale maps provide a bibliography for the original geological mapping. Red Deer Lake ! WINNIPEGOSIS Edge-matching of adjoining 1:250 000 scale map sheets is based on data from the Shuttle Tp 45 1 Tp 45 Radar Topography Mission Digital Elevation Model (SRTM DEM ) as interpreted by the MGS. Other polygon inconsistencies were modified in a similar manner. Geology (colour) is draped over a shaded topographic relief map (grey tones) derived from the SRTM DEM. Grand Bay 1 Island United States Geological Survey 2002: Shuttle radar topography mission, digital elevation model, Manitoba; United Westgate National Mills States Geological Survey, URL <ftp://edcsgs9.cr.usgs.gov/pub/data/srtm/>, portions of files N48W88W.hgt.zip ! Barrows Powell ! ! ! through N60W102.hgt.zip, 1.5 Mb (variable), 90 m cell, zipped hgt format [Mar 2003]. YZ77 0 t 0 n 0 i Tp 44 o 0 LEGEND P 5 8 Tp 44 t 5 al Baden S Quaternary ! 0 0 0 0 ORGANIC DEPOSITS: peat, muck; <1–5 m thick; very low 5 Pelican 8 5 O er relief wetland deposits; accumulated in fen, bog, swamp, and iv Shoal River R ! marsh settings ! Bay Pelican Rapids LAKE SHORELINE SEDIMENTS: sand and gravel; 1–2 m thick; ck Lm ro beaches; formed by waves at the margins of modern lakes ep te Tp 43 Tp 43 S COLLUVIUM: landslide debris, eroded slopes, sheet flood Mafeking ! C deposits associated with steep slopes EOLIAN: sand and minor silt; dunes, blowouts and undulating E plains; generally overlies deltaic sediments, coarse lacustrine WINNIPEGOSIS sediments, or glaciofluvial deposits r e Tp 42 iv Tp 42 YZ10 R North ALLUVIAL SEDIMENTS: sand and gravel, sand, silt, clay, Steeprock Kircro A organic detritus; 1–20 m thick; channel and overbank Bellsite Lake ! L sediments; reworked by existing rivers and deposited primarily ll as bars e 0 B 0 0 5 2 8 MARGINAL GLACIOLACUSTRINE SEDIMENTS: sand and South 5 Armit Steeprock Ls gravel; 1–20 m thick; beach ridges, spits, bars, littoral sand and Lake 0 gravel; formed by waves at the margin of glacial Lake Agassiz 0 0 5 Lake Bell Tp 41 2 Tp 41 8 5 OFFSHORE GLACIOLACUSTRINE SEDIMENTS: clay, silt, minor Swan Lc Lake Indian Birch sand; 1–20 m thick; very low relief massive and laminated deposits; ! deposited from suspension in offshore, deep water of glacial Lake Agassiz; commonly scoured and homogenized by icebergs 10 YZ Pelican DISTAL GLACIOFLUVIAL SEDIMENTS: fine sand, minor gravel, Gs thin silt and clay interbeds; 1–75 m thick; subaqueous outwash fans; Birch deposited in glacial Lake Agassiz by meltwater turbidity currents; Tp 40 Tp 40 commonly reshaped by wave erosion and reworked by wind Lake Lake PROXIMAL GLACIOFLUVIAL SEDIMENTS: sand and gravel; G 1–20 m thick; complex deposits, belts with single or multiple esker ridges and kames, as well as thin, low-relief deposits; deposited in contact with glacial ice by meltwater Birch River Island ! r TILL: diamicton; 1–75 m thick; low-relief, commonly streamlined deposits; subglacial e iv deposits; largely derived from shale above the Manitoba Escarpment, carbonate rocks R Tp 39 Tp 39 0 in the central lowlands, and crystalline rocks in areas of Precambrian terrane; 0 0 0 thicker sequences consist of multiple units of varying texture; commonly scoured by icebergs; Whitefish 0 8 5 covered discontinuously by thin veneers (<1 m) of glaciolacustrine and glaciofluvial sediments 0 Lake Lenswood 0 0 ! 0 r 0 e 8 v i 5 R Calcareous clay diamicton, predominantly derived from Mesozoic Tm shale Tp 38 Tp 38 Calcareous silt diamicton, predominantly derived from Paleozoic Tc dolomite and limestone an lic YZ10 e r P LAKE e iv Non-calcareous sand diamicton, predominantly derived from Bowsman R ! Tp Pre-cambrian crystalline rock Pre-Quaternary Tp 37 Tp 37 dy oo Duck Bay W ! ROCK: > 75% bedrock outcrop; Cretaceous shales above the R Manitoba Escarpment, Paleozoic carbonate-dominated rocks in areas west and south of Lake Winnipeg, exposed typically as glacially striated, low-relief surfaces; in Precambrian terrane, generally k e r e e unweathered intrusive, metasedimentary, and metavolcanic rocks r v C i 0 R 0 having a glacially scoured irregular surface with high local relief 0 5 7 7 ch 5 ee Swan River Uncoloured legend blocks indicate units that do not appear on this map. b ! WINNIPEGOSIS Tp 36 Tp 36 ite 0 h 10 Renwer 10 To aid the reader a shadow effect has been added to exaggerate the topographic relief. 0 ! 0 W YZ YZ g 5 n rin 7 a oa Minitonas 7 R ! w 5 S Briggs Spur ! Published by: Manitoba Industry, Economic Development and Mines Manitoba Geological Survey, 2004 Compiled by: G.L.D. Matile and G.R. Keller YZ83 Cowan Modified from: ! Tp 35 Tp 35 Clarke, M.D. 1989. Surficial geology, Swan Lake, Manitoba-Saskatchewan; Geological Survey of Canada, "A" Series Map, Map 1697A, Scale 1:250 000. YZ20 Pine Creek Kenville ! 52° ! 52° Camperville ! Red 300 000 325 000 YZ83 350 000 375 000 400 000 425 000 102° 100° R 29 W R 28 W R 27 W R 26 W R 25 W R 24 W R 23 W R 22 W R 21 W R 20 W R 19 W Scale 1:250 000 0 10 20 30 Kilometres ! A brief description of the Quaternary landscape of southern Manitoba Major landforms: southern Manitoba Major landforms: NTS 63C 100° 98° 96° 102° 100° Eastward-facing bedrock escarpments culminating in cuestas which form the Manitoba Escarpment provide a foundation for the G 53° 53° 53° 53° eo NTS 63C The Pas Moraine r M ge present-day landscape of southern Manitoba. To the east, the landscape is dominated by Precambrian rocks and bedrock structure, o Is SURFICIAL GEOLOGY COMPILATION MAP SERIES ra l i an such as faulting, is commonly visible. ne d Dead-ice SG-63C Above the Manitoba Escarpment, the landscape is dominated by hummocky moraine or dead-ice topography, streamlined topography topography and glacial spillways. Many areas are covered by thick sequences of glacial till representing numerous glacial episodes Streamlined landforms Precambrian dating back more than 100,000 years. The most recent glacial advances were from the northwest. Glacial till tends to be clay rich. shield 52° The Interlake is dominated by streamlined landforms and in lower areas, glaciolacustrine depositional basins. Quaternary sediments 52° Surficial geology of the Swan Lake map sheet tend to be relatively thin and the preservation of older sediments is uncommon, limited to bedrock protected areas such as Dead-ice B e escarpments. Bedrock outcrops are common. Glacial advance was generally from the northwest, parallel to the streamlined topography d (NTS 63C), Manitoba r o c landforms. Glacial till is typically silt rich. Glacial retreat occurred in a series of steps marked by moraines: the Darlingford Moraine k f a u Dead-ice 100° 96° 92° 88° (~11,000 years old); the Sandilands Moraine, which represents the interlobate position of the Rainy lobe from the northeast and the lt s topography Red River lobe from the northwest; the Birds Hill–Belair Moraine; the Teulon Moraine; and The Pas Moraine (~9000 years old). 60° U p 51° Index Map George Island Moraine, contemporaneous with and to the east of The Pas Moraine, is another ice margin of the retreating Rainy 51° pe 64N 64O 64P 54M r Precambrian Streamlined Ca G Saskatchewan A m l ac shield lobe. s p ia Landforms s b l f e e i lu n l l te n 54L 54K Dead-ice i 64K 64J 64I 58° i w s b a topography a r In the Precambrian shield, rock outcrops dominate the landscape. Quaternary sediments are commonly thick, but discontinuous, o v o i l 58° n e im e - M e c i rarely completely infilling the bedrock lows. Older sediments, including saprolites, are often preserved in the bedrock lows where n r t u i 54F s i o 64F 64G 64H 54E t a p a f 54G r l i s o c l e a they are protected from glacial erosion. Glacial advance was generally from the northeast. Glacial till is typically sand rich. l c N w r a M B b o 54A r a r n – o t p l y o l n h l i a e 54B Teu t a 54D 54C H e s 64C 64B 64A 56° As the glaciers retreated, glacial lakes Souris and Hind formed and drained, and glacial Lake Agassiz expanded northward, s g t d la 50° 50° Portage la Prairie ir c 56° B ia 53O progressively covering the entire area below the Manitoba Escarpment.