Pleistocene Glacial Lake Sequences in the Foothills, Southwestern Alberta, Canada

1974 ◽  
Vol 11 (9) ◽  
pp. 1220-1235 ◽  
Author(s):  
N. F. Alley ◽  
S. A. Harris
Keyword(s):  
Ice Sheet ◽  
Laurentide Ice Sheet ◽  
Glacial Lake ◽  
Glacial Lakes ◽  
The Third ◽  
Proglacial Lakes ◽  
Bodies Of Water ◽  
Relationship Of

Three separate advances of Laurentide ice during the preWisconsin and Early Wisconsin led to the formation of proglacial lakes in the Foothills of southwestern Alberta. Lakes formed in both the advance and recessional stages, the most extensive occurring during the latter. Evidence of lakes formed by the first advance is fragmentary, but for the later advances, the occurrence of extensive glaciolacustrine deposits and related features attests to the presence of former large bodies of water. Two lakes (Glacial Lakes Oldman and Westrup) resulted from the second advance of Laurentide ice into the Foothills. Damming of Cordilleran meltwaters by the third (Early Wisconsin) Laurentide ice sheet to affect the area, led to the formation of Glacial Lake Caldwell and the development of complex flights of valley train terraces along the Oldman and Crowsnest River valleys.The relationship of the proglacial lakes to the ice fronts substantiates the stratigraphic evidence that the Cordilleran and Laurentide ice-maxima during each advance were not synchronous and that the valley glaciers had receded considerably before the Continental ice sheet advanced into the Foothills of southwestern Alberta.

Late Wisconsinan and Holocene history of southwestern Saskatchewan

1994 ◽  
Vol 31 (12) ◽  
pp. 1822-1837 ◽  
Author(s):  
Rudy W. Klassen
Keyword(s):  
Ice Sheet ◽  
Laurentide Ice Sheet ◽  
Glacial Lakes ◽  
Grassland Vegetation ◽  
Southern Limit ◽  
Northern Margin ◽  
The North ◽  
Proglacial Lakes ◽  
History Of ◽  
Late Wisconsinan

The Late Wisconsinan Laurentide Ice Sheet reached the limit of glaciation along the north-facing slope of the unglaciated part of the Cypress Hills nunatak, but elsewhere around the Cypress Hills and Wood Mountain uplands of southwestern Saskatchewan it did not reach the limit of glaciation. An interval of deglaciation was followed by a readvance of the ice sheet, about 15 ka, to a position near the Late Wisconsinan limit, and was marked by strong flow of Keewatin ice from the north and weaker flow of Hudson ice from the northeast. Final deglaciation resulted in the formation of glacial lakes around the Cypress Hills nunatak. A network of ice-marginal and subglacial trenches, presently occupied by the Frenchman Valley and its tributaries, was formed when these lakes drained along, over, and under ice towards the western part of the Wood Mountain Upland to the east. The main trench joined an ancestral part of Frenchman Valley along the ice-free southern slopes of Wood Mountain Upland. Meltwater from the ice bordering the northern margin of the upland drained southward, excavating trenches across the highest parts of the upland and deepening ancestral valleys across the southern slopes. A succession of proglacial lakes fronted parts of the ice margin as it retreated downslope to the north. The area was deglaciated about 13.5 ka. The southern limit of a north to south forest–grassland transition was established by 13 ka along the regional drainage divide across the study area. Prairie grassland vegetation covered the southern slopes of the uplands and forests of deciduous and coniferous trees covered the highest parts of uplands and drift-mantled parts of the continental glacier to the north. The belt of forest–grassland transition had shifted well to the north of the study area by 9 ka, and a climate that was warmer and drier than at present continued to about 5 ka, when conditions became somewhat cooler.

A summary of 19th and early 20th Century researchers of glacial Lake Agassiz, North America: from Noah's Flood to Upham's bathtub and beyond

2014 ◽  
Vol 33 (2) ◽  
pp. 214-226
Author(s):  
Beth Johnson
Keyword(s):  
Laurentide Ice Sheet ◽  
Glacial Lake ◽  
Early 20Th Century ◽  
Ancient Lakes ◽  
Ancient Lake ◽  
Lake Agassiz ◽  
Proglacial Lakes ◽  
Glacial Lake Agassiz ◽  
Lake History ◽  
The U.S

During the last North American deglaciation, meltwater collected along the margins of the Laurentide Ice Sheet in proglacial lakes, the largest of these being glacial Lake Agassiz, which existed for over five thousand years starting ~13,950 cal. years B.P. Lake Agassiz was first described in 1823 by mineralogist William H. Keating of the Long Expedition at a time when diluvianism was often used to explain ancient lakes. Subsequent researchers also recognized the existence of an ancient lake, but the first connections of this lake to a possible glacial source came in 1873. Starting in 1879, Warren Upham spent the next fifteen years researching and publishing on Lake Agassiz, eventually publishing his seminal work, the U.S. Geological Survey's Monograph 25 The Glacial Lake Agassiz. Some of Upham's interpretations were later challenged by William A. Johnston, who favored a more complex lake history.

Sedimentology, stratigraphy, and geomorphology of glacial Lake Calgary at Cochrane, Alberta, Canada

1999 ◽  
Vol 36 (5) ◽  
pp. 791-803 ◽  
Author(s):  
Timothy G Fisher
Keyword(s):  
Field Data ◽  
Ice Sheet ◽  
Laurentide Ice Sheet ◽  
Glacial Lake ◽  
Fluvial Sediment

Stratigraphic and sedimentologic field data in the Cochrane, Alberta, area demonstrate that glaciolacustrine sediment comprising the Calgary Formation underlies glaciofluvial and fluvial sediment of the Bighill Creek Formation, previously dated at 11.4 ka BP. A continuous, conformable contact between sediments of glacial Lake Calgary and underlying till indicates that the lake was coeval with initial deglaciation of the area. The lake formed during retreat of the Cordilleran ice up the Bow Valley that was once previously coalescent with the Laurentide Ice Sheet. Rhythmic, graded, and convoluted glaciolacustrine sediments record continuous and high rates of sedimentation in this reach of glacial Lake Calgary, further implying that the lake formed early in deglacial time.

Late Deglaciation of the Central Labrador Coast and Its Implications for the Age of Glacial Lakes Naskaupi and McLean and for Prehistory

1990 ◽  
Vol 34 (3) ◽  
pp. 296-305 ◽  
Author(s):  
Peter U. Clark ◽  
William W. Fitzhugh
Keyword(s):  
Sea Level ◽  
Ice Sheet ◽  
Late Glacial ◽  
Time Frame ◽  
Laurentide Ice Sheet ◽  
Glacial Lakes ◽  
Central Coast ◽  
Relative Sea Level ◽  
Level Curves

AbstractThe age of the marine limit and associated deglaciation has been estimated from relative sea-level curves for the Hopedale and Nain areas of the central Labrador coast as approximately 7600 ± 200 and 8500 ± 200 yr ago, respectively. These ages indicate that the ice margin remained on the coast for up to 3000 yr longer than previously estimated. Because the central coast is due east of glacial lakes Naskaupi and McLean, the earliest the lakes could have formed was <8500 ± 200 yr ago, with their largest phases being fully established only after 7600 ± 200 yr ago. This suggests that the age of the lakes, and associated deglaciation of the central Labrador-Ungava region, is younger by at least 1500 yr than previously estimated. A late-glacial marine-based ice mass in Ungava Bay that dammed the lakes collapsed ca. 7000 yr ago. Within this time frame, therefore, the glacial lakes only existed for <500 yr. The persistence of the Laurentide Ice Sheet margin on the central Labrador coast until 7600 yr ago probably restricted the northward movement of early prehistoric people into northern Labrador.

scholarly journals The observed postglacial recovery of Québec and Nouveau-Québec Since 12,000 BP

2011 ◽  
Vol 31 (3-4) ◽  
pp. 389-400 ◽  
Author(s):  
J. T. Andrews ◽  
K. Tyler
Keyword(s):  
Ice Sheet ◽  
Laurentide Ice Sheet ◽  
Hudson Bay ◽  
Control Points ◽  
James Bay ◽  
Sea Levels ◽  
Ice Edge ◽  
Proglacial Lake ◽  
Relationship Of ◽  
The Relationship

Radiocarbon dated relative sea levels, the tilts of proglacial lake shorelines and raised marine shorelines, the directions of the tilt of these features, and postglacial delevelling are used to construct six isobase maps showing relative sea level movements over the last 12,000, 10,000, 8000, 4000, and 2000 years, No map has more than 30 control points and usually there are only 12 "good" points controlling the isobase patterns. Each map shows the relationship of the isobases to the current ice sheet extent. Along the southern margin of the Laurentide Ice Sheet, the maximum postglacial emergence has been quite uniform with the 240 to 200 m isobase always close to the ice margin. Along the northeastern margin of the ice sheet, the postglacial emergence at the retreating ice edge was closer to 100 m. Equidistant diagrams are drawn along planes southeast from southern Hudson Bay and eastward from Southampton Island. If these diagrams are compared on a Shoreline Relation Diagram, the two profiles appear similar and compare moderately well with a theoretical SR Diagram published in 1969. The isobases show a major uplift center located around the area of James Bay and southern Hudson Bay where a maximum emergence of nearly 300 m occured in the last 7500 years. High marine limits southwest of Ungava Bay need to be dated because if they date close to 8000 BP as we suggest, then more emergence is suggested for the region southwest of Ungava Bay than we currently allow for.

scholarly journals The pattern and style of deglaciation at the Late Wisconsinan Laurentide and Cordilleran ice sheet limits in northeastern British Columbia

2017 ◽  
Vol 54 (1) ◽  
pp. 52-75 ◽  
Author(s):  
David H. Huntley ◽  
Adrian S. Hickin ◽  
Olav B. Lian
Keyword(s):  
British Columbia ◽  
Ice Sheets ◽  
Ice Sheet ◽  
Yukon Territory ◽  
Glacial Lake ◽  
Glacial Lakes ◽  
Lake Formation ◽  
Late Wisconsinan ◽  
Cordilleran Ice Sheet ◽  
Lake Deposits

This paper reports on the landform assemblages at the northern confluence of the Late Wisconsinan Laurentide and Cordilleran ice sheets with montane and piedmont glaciers in the northern Rockies and southern Mackenzie Mountains. Recent observations in northeastern British Columbia refine our knowledge of the pattern and style of ice sheet retreat, glacial lake formation, and meltwater drainage. At the onset of deglaciation, confluent Laurentide and Cordilleran terminal ice margins lay between 59°N, 124°30′W and 60°N, 125°15′W. From this terminal limit, ice sheets retreated into north-central British Columbia and Yukon Territory, with remnant Cordilleran ice and montane glaciers confined to mountain valleys and the Liard Plateau. Distinctive end moraines are not associated with the retreat of Cordilleran ice in these areas. Laurentide ice retreated northeastward from uplands and the plateaus; then separated into lobes occupying the Fort Nelson and Petitot river valleys. Ice-retreat landforms include recessional end moraines (sometimes overridden and drumlinized), hill–hole pairs, crevasse-fill deposits, De Geer-like ribbed till ridges, hummocky moraines, kames, meltwater features, and glacial lake deposits that fall within the elevation range of glacial Lake Liard and glacial Lake Fort Nelson (ca. 840–380 m). Meltwater and sediment transport into glacial lakes Fort Nelson, Liard, Nahanni, and Mackenzie was sustained by remnant ice in the Liard River and Fort Nelson River drainage basins until the end of glaciation. Optical dating of sand from stabilized parabolic dunes on the Liard Plateau indicates that proglacial conditions, lake formation, and drainage began before 13.0 ± 0.5 ka (calendar years). The Petitot, Fort Nelson, and Liard rivers all occupy spillways incised into glacial deposits and bedrock by meltwater overflow from glacial lakes Peace and Hay.

An inventory of Antarctic sub-glacial lakes

1996 ◽  
Vol 8 (3) ◽  
pp. 281-286 ◽  
Author(s):  
M.J. Siegert ◽  
J.A. Dowdeswell ◽  
M.R. Gorman ◽  
N.F. McIntyre
Keyword(s):  
Ice Sheet ◽  
East Antarctica ◽  
Glacial Lake ◽  
Ice Thickness ◽  
Minimum Length ◽  
Glacial Lakes ◽  
University Of Cambridge ◽  
Radio Echo Sounding ◽  
Polar Research Institute ◽  
Lake Type

An extensive analogue database of 60 MHz radio-echo sounding records of Antarctica (covering 50% of the ice sheet) is held at the Scott Polar Research Institute, University of Cambridge. This database was analysed in order to determine the presence and location of Antarctic sub-glacial lakes. In total, 77 sub-glacial lake-type records were identified, 13 more than detected in previous studies. An inventory of these sub-glacial lakes includes geographical coordinates, minimum length and overlying ice thickness for each lake. Information concerning the location of these lakes indicates that the majority (~70%) are found in the proximity of ice divides at Dome C and Ridge B within East Antarctica.

Sign in / Sign up

Export Citation Format

Share Document