Question

In order to carve out valleys, glaciers have to be strong enough to drag rocks and boulders down the mountainside, but what else has to happen for glaciers to create glacial valleys?

a. To create valleys, glaciers have to move at a rapid rate of several miles a day.
b. To create valleys, glaciers have to completely melt and freeze over thousands of years. This total melting causes solid rocks to crack and decompose.
c. To create valleys, glaciers have to be constantly retreating.
d. Glaciers have to be soft enough to move, and it is this movement that drags the rocks and boulders responsible for carving Earth’s surface.
e. To create valleys, glaciers have to be constantly advancing.

Answer 1

e. To create valleys, glaciers have to be constantly advancing.

Step-by-step explanation:

Although glaciers look like massive, solid blocks of ice, they actually move in a very slow manner, which is difficult to detect by the naked eye. The pressure that the glacier receives from the weight of the ice causes it to deform. As these changes occur, the melt water at the bottom of the glacier allows it to slide. It is this movement that allows for the formation of glaciers, as glaciers have to be constantly advancing in order to form valleys.