Monday March 21, 2011 (Landforms Created by Glacial Erosion; Glacial Deposits)

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Welcome to Chemistry

MondayMarch 21, 2011(Landforms Created by Glacial Erosion; Glacial Deposits)The Launch PadMonday, 3/21/11Why are most glaciers in the world today receding?

The Launch PadMonday, 3/21/11More ice is melting every summer than can be replaced by snowfall the next winter. This could be caused by a gradual increase in world temperatures (global warming.)

Announcements??Assignments For This Six-WeeksDate IssuedDate DueVideo Quiz - Lakes, Rivers, and Other Water Sources2/272/27WS - Running Water and Groundwater (Part 1)2/253/4PowerPoint Project Rivers (P5 only)2/283/3WS - Running Water and Groundwater (Part 2)3/23/9Video Quiz - Groundwater3/33/3Cornell Notes - Ice3/83/9WS - Ice3/9??Continue WorksheetIceLandforms Created by Glacial ErosionCertain types of special landforms can be created by glacial erosion. These include: glacial troughs As a glacier widens, deepens, and straightens a valley, it transforms a v-shaped valley into a u-shaped glacial trough.hanging valleys After a glacier has receded, the valleys of tributary glaciers are left standing above the main glacial trough and are termed hanging valleys.Landforms Created by Glacial Erosioncirques a bowl-shaped depression at the head of a glacier that was a depression where snow could accumulate, thus starting the formation of the glacier.artes sharp-edged ridges that are formed when cirques grow and the divide separating them becomes very narrow.Landforms Created by Glacial Erosionhorns several cirques surrounding a single mountain create the spires of rock called horns.fiords - glacial troughs that became submerged as the ice left the valley and sea levels rose following the Ice AgeErosional Landforms Created by Alpine GlaciersFigure 6.10 C

The Matterhorn in the Swiss Alps Figure 6.12

Figure 6.10 (top right)

Figure 6.10 (middle right)

Figure 6.10 (bottom right)

Figure 6.11A

Figure 6.11B

Glacial DepositsGlaciers pick up and transport a huge load of debris as they slowly advance across the land.Ultimately, these materials are deposited when the ice melts.In regions where glacial sediment is deposited, it can play a significant role in forming the physical landscape.Long before the theory of an extensive Ice Age was proposed, much of the soil and rock debris covering portions of Europe was recognized as coming from elsewhere.At the time, these foreign materials were believed to have been drifted into their present positions by floating ice during an ancient flood.Therefore, the term drift was applied to this sediment.Today, glacial drift is a term for sediments of glacial origin, no matter how, where, or in what form they were deposited.

Glacial DepositsTypes of Glacial Drift Till refers to material that is deposited directly by ice.

Glacial DepositsTypes of Glacial Drift Stratified drift is a sorted sediment deposited by meltwater.

Glacial DepositsTypes of Glacial Drift Boulders found in till or lying free on the surface are called glacial erratics if they are different from the bedrock below.Erratics must have been derived from a source outside the area where they are found.