Water Erosion

Explain how water erosion by groundwater can form a cave.

Groundwater can cause erosion through chemical weathering. First, water that sinks into the ground mixes with carbon dioxide to form carbonic acid, a weak acid. Carbonic acid can break down limestone. Some of the limestone changes chemically and is carried away in a solution of water. This gradually hollows out pockets in the rock. Over time, these pockets develop into large holes underground—caves or caverns.

A landscape in which a layer of limestone close to the surface erodes into deep valleys, caverns, and sinkholes is called a. loess. b. till. c. headland. d. karst topography.

D. Karst Topohraphy

A moraine is a cone-shaped deposit of calcite that builds up on the floor of a cave. TRUE OR FALSE

FALSE

landscape in which limestone is eroded to form deep valleys and caverns is called what?

Karst Topography

What five factors determine the amount of runoff in an area?

The five main factors that determine the amount of runoff in an area are the amount of rain, vegetation, type of soil, shape of the land, and how people use the land.

The major agent of erosion that shapes the land surface of Earth is what?

Water

What is an oxbow lake?

When you have meanders and they wear away at a narrow point and a lake forms

What is a tributary?

a small stream or river that runs into a larger stream or river.

water flowing over land, carrying particles of sediment is called what?

runoff

sediment deposited where a river flows into an ocean or lake is called what?

A delta

What is a delta?

A landform made of sediment that is deposited where a river flows into an ocean or lake.

What is a meander?

A looplike bend in the course of a river.

Deltas are built up by a. deposition. b. leaching. c. abrasion. d. erosion.

A. Deposition

The deposition of sediment where there is a steep drop-off into shallow, flat land can create a(n) __________.

Alluvial fan

A river flowing across a wide flood plain begins to form looplike bends called a. rills. b. meanders. c. outside curves. d. deltas.

B. Meanders

A wide sloping deposit of sediment formed where a stream leaves a mountain range is called a(n) a. divide. b. drainage basin. c. alluvial fan. d. slump.

C. Alluvial fan

Compare and contrast the features of a river near its source and far down along its course.

Near its source, a river is fast moving and flows on a steep mountain slope. It rapidly erodes a V-shaped, steep-sided valley. Its course may include waterfalls and rapids. Farther along its course, a river flows over gently sloping land. Here it flows more slowly, spreading out and eroding the land to form a wide, flat valley. As the river begins to wind from side to side, meanders form.

What is the main agent of erosion that has shaped much of Earth's surface?

Running water

An alluvial fan may form where a stream flows out of a narrow mountain valley, slows down, and deposits sediment. TRUE OR FALSE

TRUE