Explain why a glacier has a U-shaped cross section, whereas mountain stream valleys are usually V-shaped

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Erosion of valleys in mountains is caused by downward erosion by flowing water in a narrow channel. As the resulting valley walls become very steep, they fail during mass movements, which deliver debris to the stream to be carried away. Therefore, stream valleys have a V-shaped cross section with sloping hillsides descending to the stream channel. When a glacier flows through a pre-existing valley, it erodes not only at the bottom but also along the sides of the valley. The shear stress exerted against the sides and bottom of the valley erodes rock in a fashion analogous to an ice-scream scoop moving through ice cream, which leaves a broad-floored, steep-sided, U-shaped cross section.

Environmental & Atmospheric Sciences

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An oceanic trench is a deep narrow rift parallel to the crest of a mid-oceanic ridge.

Answer the following statement true (T) or false (F)

Environmental & Atmospheric Sciences

In the deep ocean, tsunami waves will travel at speeds approaching ____ km/hr

a. ?1 b. ?25 c. ?100 d. ?900 e. ?5,000

Environmental & Atmospheric Sciences

The multiple nuclei theory recognized that

A) cities grow. B) residential areas are racially segregated. C) cities develop around several nodes. D) urban sprawl has developed in cities.

Environmental & Atmospheric Sciences