Glaciers Summer Flashcards
(24 cards)
What is a glacier?
A glacier is a large mass of ice that moves slowly over land, formed by compacted snow.
What are the two main types of glaciers?
Valley glaciers (in mountains) and Ice sheets (e.g. Antarctica).
What is freeze-thaw weathering?
When water enters cracks, freezes, expands, and breaks the rock apart.
Name 2 glacial erosion processes.
Plucking and abrasion
What is plucking?
Ice freezes onto rocks and pulls them away as the glacier moves.
What is abrasion?
Rocks stuck in the glacier grind against the ground, wearing it away.
What is a corrie?
A bowl-shaped hollow where snow compacts into glacier ice.
What is an arête?
A narrow ridge formed between two corries.
What is a pyramidal peak?
A sharp peak formed where several corries meet.
What is a U-shaped valley?
A valley with steep sides and a flat floor carved by a glacier.
What is a moraine?
Deposited material left by a glacier, like rocks and debris.
Name types of moraines & where they are located.
Lateral- sides, Medial-middle, Terminal-bottom.
What is a drumlin?
A smooth, oval-shaped hill made of glacial till.
What is glacial deposition?
When glaciers drop material as they melt.
What happens when glaciers melt?
Sea levels rise, habitats are lost, and freshwater is reduced.
What is glacial retreat?
When a glacier shrinks due to melting faster than accumulation.
What are contour lines?
They are lines on a map that join points of the same height
What is Transport?
The material that gets carried away by the glacier
What is Glacial Till made up of?
Roc k, Stones, Sand & Clay
How is a Glacier made?
Layers of snow build up which then overtime the layers below get compacted to ice
What is a Hanging Valley?
A hanging valley is a smaller valley that is located above the main valley floor.It is called “hanging” because it looks like it’s hanging off the side of a larger valley. This happens because the main glacier erodes the land more deeply than smaller glaciers in side valleys.
What is a U-shaped valley and how is it made?
A U-shaped valley is a wide valley with steep sides made by a glacier. A river in the middle of the valley carves up a V -shaped valley but when the glacier bulldozes its way down it deepens and becomes a U-shaped valley.
What do you call a crack in a Glacier?
A Crevises
What are scrape marks called?
Striations
