Earth's Materials

Which of the following can change the surface of Earth by turning v-shaped valleys into u-shaped valleys and carrying large boulders long distances?

• glaciers

• rivers

• sand dunes

• wind storms

Stalagmites are structures found on the floors of caves and are made of mineral deposits. Stalagmites provide evidence for how moving water can change Earth materials because stalagmites –

• grow upward, while stalactites grow downward from the ceiling.

• are sometimes found in or near pools of water underground.

• may be small and delicate or very tall and massive

• form where water containing dissolved minerals constantly drips.

Which observations about the Rocky Mountains and the Appalachian Mountains would support the claim that exposure to weathering and erosion over time can change land forms?

• The Appalachian Mountains are found in the eastern United States and the Rocky Mountains are found near the west coast.

• The shorter and more rounded Appalachian Mountains are more than four times older than the taller and more jagged Rocky Mountains.

• The length of the Appalachian chain is approximately 2,400 kilometers, and the Rocky Mountain chain is about twice as long.

• The Appalachian Mountains are composed mostly of sedimentary rocks while the Rocky Mountains also contain other rock types.

What is the agent of erosion and transportation responsible for

the creation of deltas?

• ice

• wind

• water

• gravity

The rate of erosion would increase if the:

• Average Rainfall increased

• Wind speed decreased

• Slope of the land decrease

• Vegetation cover increased