Question

Which of the following options is/are correct for movement of warm-base glaciers?

• A. Movement is dominated by basal sliding
• B. Internal deformation involving slippage within and between ice crystals leads to glacial movement
• C. Internal deformation is governed by shear stress following Power Law
• D. Vertical profile of glacier flow velocity is maximum at the base and decreases upwards

Hint:

Warm-based glaciers experience basal sliding and internal deformation, leading to movement. The velocity of flow decreases with height above the base due to friction and resistance from the glacier bed.

Answer 1

The Correct Option is A, B, C

Understanding Glacier Movement
Warm-based glaciers, which have temperatures near the melting point at their base, exhibit different types of movement compared to cold-based glaciers.

Option (A): This is correct because basal sliding dominates the movement of warm-based glaciers, where the ice slides over the bedrock due to water at the base.

Option (B): This is correct because internal deformation occurs when ice crystals slip past each other, leading to movement within the glacier.

Option (C): This is correct because the internal deformation of glaciers is governed by shear stress, which follows the Power Law, where the ice deforms more easily under greater stress.

Option (D): This is correct because the velocity of glacial flow is typically greatest at the base and decreases upwards due to friction with the underlying surface.