Chapter 10: Glacier, Deserts, Wind

Continental ice sheets

The largest glaciers that currently cover areas such as Antarctica and Greenland.

What is not true of glaciers?

Glaciers do not exist only at high altitudes; they can also exist in lower altitudes under certain conditions.

Today, glaciers cover approximately what percent of the earth's surface?

About 10 percent.

What applies to a valley glacier that is advancing?

Accumulation exceeds wastage.

What is a crack in a glacier called?

A crevasse.

At the base of a glacier, the ice moves by what process when water is present?

Basal slip.

What is the maximum depth you are likely to fall into a crevasse?

Up to 50 meters.

What happens if the glacial budget is balanced?

The terminus of the glacier is stationary.

What part of a glacier generally involves abrasion and plucking?

The bottom or base.

What are erosional features produced by valley/alpine glaciers?

Cirques.

What is likely to host a waterfall or steep rapids today?

A hanging valley.

What is not a major factor controlling glacial erosion?

The type of rock beneath the glacier.

What does the term stratified drift mean?

Any sediments deposited by meltwater.

What is a rock carried a long distance from its origin by glacial ice called?

An erratic.

What represents a former meltwater channel or tunnel in glacial ice?

An esker.

What forms when a block of ice is buried in drift and subsequently melts?

A kettle.

What is NOT true about glacial tills?

They are deposited by glacial meltwater.

What period of geologic history coincides with the last ice age?

The Pleistocene Epoch.

What is considered the most likely cause for Earth having glacial and interglacial periods?

Variations in the earth's orbit.

What do Milankovitch cycles explain?

The cycles of cold and warm climates during the Ice Ages based on variations in the earth's orbit.