The Solid Earth - Chapter 4: Glacial Movement Flashcards
The name for the movement of glacial ice
flow
Name the two basic types of ways that ice flows
internal movement within the ice
whole ice mass slipping
The lowest portions of most glaciers are thought to move by this sliding process
whole ice mass slipping along the ground
True or false: just as in streams, frictional drag with the bedrock floor results in the lower portions of the glacier moving more quickly
False; SLOWLY
The uppermost portion of a glacier that consists of brittle ice
zone of fracture
When the glacier moves over irregular terrain, the zone of the fracture is subjected to tension with cracks called ___ resulting
crevasses
Where is the flow of the glacier the greatest?
The center
Why do the sides of the glacier move slower than the center?
Friction with valley walls
What is the raw material from which glacial ice originates?
snow
Glaciers are constantly gaining and losing __
ice
Where does snow accumulation and ice formation occur
Zone of accumulation
The area beyond the zone of accumulation where snow and ice from before melt
zone of wastage
This process creates icebergs in places where glaciers reach the sea as large pieces of ice break off the front
calving
The movement of the glacier (remaining, progressing, retreating) depends on the budget of the glacier or the balance between accumulation and ____
ablation
Is ablation or accumulation greater if the glacier is retreating
Ablation