Ice Sheets and Glacial Rebound

A thick accumulation of ice across a continent causes the crust to sink into the mantle. When the ice melts and disappears, the crust rises again. Large areas of land that were pushed down by the weight of glaciers during the last ice age are still rising slowly today. this phenomenon is known as post glacial rebound or glacial isostatic rebound. The eastern part of Canada around Hudson Bay is a good example of a region undergoing rebound. Rebound, a type of crustal uplift, occurs when land rises because the weight that was once on it is removed.

This week, we will be finishing our activities on glaciers by completing a laboratory activity on glacial rebound. The next topic will be Continental Drift and Plate Tectonics. We aim to start this topic on or about Wednesday, March 11th.

Homework # 5: Due Tuesday, March 10, 2009

Textbook: read chapter 15.4, pages 330-333. Do questions 1-4

Homework # 6: Due Monday, March 16, 2009

Textbook: read Chapter 8, pages 172-175. Do questions 1-5.

Reminder: the end of the marking period is Friday the 13th. Prepare for a quiz on Friday.

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