Exam 14: The Work of Wind and Deserts

How does saltation by wind differ from that in streams?

A common mode of mass wasting in deserts is:

Wind deposits composed of sand-sized particles that are deposited near their source are called ____________________.

What produces the worldwide pattern of east-west-oriented wind belts?

What are the three main sources from which loess is derived?

Alluvial fans are composed of sediment that is ____________________-sorted and ____________________ stratified.

Besides deserts, where does wind play a role as a significant geologic agent?

Why do most desert streams never reach the sea?

Equatorial regions receive the most heat, while polar regions receive the lowest. Therefore, what air pressures would you expect to be characteristic of these regions?

Briefly explain why sand is moved by wind before clay and silt during wind erosion.

Dunes that form long-parallel ridges of sand aligned generally parallel to the direction of the prevailing winds where sand supply is somewhat limited are ____________________ dunes.

Briefly describe the four main dune types and how they differ from each other?

The deflection of a moving mass from a straight line is known as the ____________________.

Briefly explain how a rain-shadow desert forms.

Think about what you learned about sedimentary rocks. Why would ancient cross-bedded sandstone beds, as seen in Zion National Park, Utah, be useful to geologists?

The Coriolis effect causes winds to be deflected to the ____________________ of their direction of motion in the Northern Hemisphere and to the ____________________ of their direction of motion in the Southern Hemisphere.

Air flows from ____________________ pressure regions to ____________________ pressure regions.

What is air pressure, and how does it vary with temperature?

Although loess may originate in deserts, it is not deposited in them.

Although loess forms in only a few environments, it covers approximately ____________________% of Earth's land surface.