词条 | Lake Chouteau |
释义 |
| name = Lake Chouteau | image = Glacial lakes in Montana.jpg | caption = Map of Montana showing Lake Chouteau. | location = Teton, Montana | coords = {{coord|47.812155|-112.183268|region:US_type:landmark|display=inline,title}} | lake_type = Glacial lake (former) | inflow = Laurentide Ice Sheet | outflow = Lake Great Falls | catchment = | basin_countries = United States | length = about {{convert|20|miles|km}} | width = about {{convert|5|miles|km}} | area = varied | depth = | max-depth = | volume = | residence_time = | shore = | elevation = {{convert|3500|m|ft|abbr=on}} | reference = [1] }} Lake Chouteau was a glacial lake formed during the late Pleistocene along the Teton River. After the Laurentide ice sheet retreated, water melting off the glacier accumulated between the Rocky Mountains and the ice sheet. The lake drained along the front of the ice sheet, eastward towards the Judith River and the Missouri River. The maximum advance of the Laurentide ice sheet blocked the drainages of north- and east-flowing rivers, forming glacial lakes along the margin of the ice. On the western Montana plains the Shelby lobe blocked the [Milk River (Alberta–Montana)|[Milk River]], creating glacial Lake Twin River. Tributaries of the Marias River were also blocked by the Shelby lobe, leading to the formation of glacial lakes Cutbank and Choteau. The Loma sublobe blocked the Missouri north of the Highwood Mountains, forming glacial Lake Great Falls. A lake also formed in the Musselshell River basin.[2] IdentificationScattered limestone boulders and cobbles sitting on bedrock with in the Teton River basin, east of the river outlet from the piedmont glacial lobe and west of Choteau is evidence of several pre-Pinedale piedmont glaciations. The clasts made up of boulders and cobbles from the limestone-rich, mountain-source and is a nonglacial [[Alluvium |alluvium]] of Tertiary age that formerly covered the bedrock surfaces.[3] Paleosols identified as part of the Bull Lake till units or outwash units are weakly developed. They represent two stades of a single glaciation. They are dated from the early Bull Lake lateral moraines in the Glacier National Park at approximately 160 thousand years before present (YBP), the late Bull Lake lateral moraines are is approximately 140 thousand YBP.[3] See also
References1. ^Physiography and Glacial Geology of Eastern Montana and Adjacent Areas; William C. Alden; United States Government Printing Office: Washington, D.C.; 1932 {{Pleistocene Lakes and Seas}}2. ^Geologic Framework and Glaciation of the Central Area, 1-1-2006; Christopher L. Hill; Boise State University, Boise, Idaho; 2006 3. ^1 Map Showing Spatial and Temporal Relations of Mountain and Continental Glaciations on the Northern Plains, Primarily in Northern Montana and Northwestern North Dakota; David S. Fullerton, Roger B. Colton, Charles A. Bush, and Arthur W. Straub; Pamphlet to accompany Scientific Investigations Map 2843; U.S. Department of the Interior, U.S. Geological Survey; Washington, D.C., 2004 6 : Former lakes|Geology of Montana|Glacial lakes of the United States|Natural history of Montana|Proglacial lakes|Teton County, Montana |
随便看 |
|
开放百科全书收录14589846条英语、德语、日语等多语种百科知识,基本涵盖了大多数领域的百科知识,是一部内容自由、开放的电子版国际百科全书。