The Fascinating Phenomenon of Glacial Advances

What is the term for the forward movement of the outer margin of a glacial body?

A. Ablation

B. Accumulation

C. Glacial flow

D. Glacial advance

Answer:

The forward movement of the outer margin of a glacial body is called a glacial advance.

Glacial advances are a fascinating natural phenomenon that occur when glaciers grow and expand, pushing their outer margins forward. This movement is typically caused by the accumulation of snow and ice in the upper parts of the glacier.

During a glacial advance, the glacier can move at varying speeds, influenced by factors such as the slope of the terrain and the amount of ice and snow available. The movement is not uniform across the width of the glacier, with the central portion generally moving faster than the sides, leading to the formation of crevasses and other surface features.

These advances have significant impacts on the landscape, as the moving glacier erodes rock and soil, shaping valleys and terrain. The glacier can also transport large amounts of sediment, including rocks and boulders, which are deposited when the glacier retreats.

Glacial advances are a beautiful display of the dynamic forces of nature, shaping our planet's surface over time.