Exam 14: Deserts and Wind

Loess is:

The largest loess deposits in the world are found in __________.

Because sand grains are relatively heavy, wind rarely lifts sand more than 1 meter above the ground and carries it only short distances.

A dry desert lake bed is a __________.

Much of the rich loess of the central plains of the United States is the result of the Pleistocene Ice Age.

Large __________ deposits accumulated in North America during the Pleistocene Ice Age from wind transporting and depositing big amounts of silt.

The leeward face of a dune is called the __________ __________.

When dunes are buried by younger sediment and lithified, __________ __________ form.

The Atacama Desert along the west coast of South America is so dry that, on the average, portions of Peru and Chile receive no rainfall for a decade or more.

A streambed that is dry most of the year is called a __________.

Erosion of soil by wind is __________.

When moisture-laden air flows over a mountain range, it cools and loses its ability to hold moisture.

Human mismanagement can cause the conversion of semiarid land to arid land in a process called __________.

Water vapor that has condensed over a mountain range is more likely to fall as rain and snow:

A/an __________ is a broad, gently sloping depositional surface formed by merging alluvial fans.

The effects of abrasion by windblown sand and silt:

Outside of the polar regions, the Earth's land surface is __________ desert.

Because Death Valley has no external drainage, the __________ eroded from surrounding mountains creates bajadas, pediments, and alluvial fans.

Large desert rivers, like the Nile River, receive most of their water from:

In fossil dunes: