Glaciofluvial deposits in the context of "Esker"

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⭐ Core Definition: Glaciofluvial deposits

Fluvioglacial landforms or glaciofluvial landforms are those that result from the associated erosion and deposition of sediments caused by glacial meltwater. Glaciers contain suspended sediment loads, much of which is initially picked up from the underlying landmass. Landforms are shaped by glacial erosion through processes such as glacial quarrying, abrasion, and meltwater. Glacial meltwater contributes to the erosion of bedrock through both mechanical and chemical processes.Fluvio-glacial processes can occur on the surface and within the glacier. The deposits that happen within the glacier are revealed after the entire glacier melts or partially retreats. Fluvio-glacial landforms and erosional surfaces include: outwash plains, kames, kame terraces, kettle holes, eskers, varves, and proglacial lakes.

Meltwater streams and formed by glaciers, especially in warmer seasons. Supra-glacial streams, those above the glacial surface, and subglacial streams, those beneath the glacial surface. At the interface of the glacier and the underlying land surface, the immense weight of the glacier causes ice to melt and produces subglacial meltwater streams. These streams under immense pressure and at high velocities along with the overlying weight of the glacier itself are able to carve into landscapes and pluck sediment from the ground. This sediment is transported as the glacier advances. In warmer seasons, the glacier diminishes and retreats. This process leaves behind dropped sediment in the form of depositional landforms. The two processes of advancement and retreat have the power to transform a landscape and leave behind a series of landforms that give great insight into past glacial presence and behavior. Landforms that result from these processes include moraines, kames, kettles, eskers, drumlins, plains, and proglacial lakes.

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Glaciofluvial deposits in the context of Blue Ribbon Mine

Gold was discovered in the Yentna-Cache Creek Mining District in the U.S. state of Alaska (also known separately as the Yentna District or Cache Creek District) of the upper Susitna River Valley in 1898, soon followed by claim staking. Placer mining was reported in the Cache Creek drainage of the Dutch Hills by 1906. Quaternary glaciofluvial deposits, alluvial deposits, and Cenozoic conglomeratic white quartz-breccia units have been mined in the Dutch Hills. About 200,000 oz (12,000 lb; 5,700 kg) of gold has been produced from these placer deposits.

By 1927, a road from Talkeetna was constructed into the mining area, known today as The Petersville Road. The mining camp of Petersville, Alaska served as the area Post Office for several years in the late 1920s and early 1930s. Two areas have been set aside for recreational gold mining, the North and South units of the Petersville State Recreation Mining Areas. Many smaller one-man and family placer mining operations continue today.

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Glaciofluvial deposits in the context of Outwash plain

An outwash plain, also called a sandur (plural: sandurs), sandr or sandar, is a plain formed of glaciofluvial deposits due to meltwater outwash at the terminus of a glacier. As it flows, the glacier grinds the underlying rock surface and carries the debris along. The meltwater at the snout of the glacier deposits its load of sediment over the outwash plain, with larger boulders being deposited near the terminal moraine, and smaller particles travelling further before being deposited. Sandurs are common in Iceland where geothermal activity accelerates the melting of ice flows and the deposition of sediment by meltwater.

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