GlaciersBy: Naomi Cary & Elizabeth

Baldwin

What are glaciers?Glaciers are enormous masses of moving ice.

Glaciers are heavy and are capable of moving across the Earth’s surface. They erode, move, and deposit large quantities of materials. Glaciers form in areas that are very cold and have snow year round. These usually form in polar regions.

Alpine GlaciersAlpine glaciers form in mountainous areas.

There is one common type of alpine glaciers; valley glaciers.

Valley glaciers are formed by stream erosion. These glaciers flow downhill slowly, and

widening the valleys into U-shaped valleys.

Continental GlaciersContinental glaciers are huge continuous

masses of ice.The largest type of a continental glacier is a

continental ice sheet.These ice sheets can cover millions of square

kilometers with ice.

IcebergsIcebergs are large pieces of ice that break off

of ice shelves and drift into the oceans.Icebergs form by a process called calving.Icebergs are hazards for ships because they

cannot see how far the icebergs extends.

CrevassesCrevasses occur when glaciers flow forward.Crevasses are large cracks that form where

the glacier picks up speed or flows over a high point.

These cracks happen because the ice cannot stretch quickly.

These can be very dangerous for people who are traveling across glaciers because a bridge layer of snow can hide these cracks from view.

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LandformsAlpine glaciers carve out rugged features in

the mountain rocks through which they flow.Continental glaciers smooth the landscape by

scraping and removing features that existed before the ice appeared.

Landscapes formed by Alpine glaciers.

Retreating Glacier

Glacial DriftGlacial drift is all the material carried and

deposited by glaciers. There are two main types, stratified drift and

till deposits. This is based on whether the material is

sorted or unsorted.

Stratified driftStratified drift happens when rock material

that has been sorted and deposited in layers by water flowing from the melted ice.

Many streams are created from the melting water of a glacier.

The streams carry a lot of sorted material, which is later deposited in front of the glacier.

Till DepositsTill is unsorted rock material that is

deposited directly by the ice when it melts. The till is made up of different sizes of rock

material. The most common till deposits are moraines.Moraines generally form ridges along the

edges of glaciers.They are produced when glaciers carry

material to the front of the ice and along the sides.

SummaryGlaciers are large masses of ice that move

across the world. There are two types of glaciers; Alpine and Continental.

Alpine glaciers create; horns, cirques, arêtes, u-shaped valleys, and hanging valleys. Continental glaciers create; ice shelves, icebergs, and crevasses.

Glaciers carry material and deposits. There are two types of glacial drift; stratified drift and till deposits.