Surface Processes

Which event is an example of chemical weathering?

• rocks falling off the face of a steep cliff

• feldspar in granite being crushed into clay-sized particles

• water freezing in cracks in a roadside outcrop

• acid rain reacting with limestone bedrock

The amount of chemical weathering will increase if

• air temperature decreases and precipitation decreases

• air temperature increases and precipitation decreases

• air temperature decreases and precipitation increases

• air temperature increases and precipitation increases

The cross section below shows sedimentary bedrock layers A, B, C, and D exposed at Earth’s surface. Which layer appears to be the least resistant to weathering?

• A

• B

• C

• D

The accompanying diagram shows granite bedrock with cracks. Water has seeped into the cracks and frozen. The arrows represent the directions in which the cracks have widened due to weathering. Which statement best describes the physical weathering shown by the diagram?

• Enlargement of the cracks occurs because water expands when it freezes.

• This type of weathering occurs only in bedrock composed of granite.

• The cracks become wider because of chemical reactions between water and the rock.

• This type of weathering is common in regions of primarily warm and humid climates.

Humus, which is formed by the decay of plant and animal matter, is important for the formation of most

• soils

• minerals

• delicious dip for pita chips

• surface bedrock

Which factor has the most influence on the development of soil?

• climate

• longitude

• amount of eroded sediment

• slope of the landscape

A landscape region that has broad, U-shaped valleys with polished and grooved bedrock was most likely formed by

• running water

• glaciers

• wind

• wave action

Which climactic conditions normally produce the greatest chemical weathering?

• cool and dry

• cool and wet

• warm and dry

• warm and wet

Which agent of erosion is most likely responsible for the deposition of sandbars along ocean shorelines?

• glaciers

• mass movement

• wave action

• wind action

The largest sediment particles that can be transported by a stream traveling at a velocity of 200 centimeters per second are

• silt

• cobbles

• pebbles

• sand