Chapter 19 Deserts and Wind
What is a playa commonly occupied by?
an ephemeral lake
What is an ephemeral stream?
an intermittent stream that carries water only in response to specific episodes of rainfall
What does saltating mean?
Sand grains are lifted by the wind, leap a short distance, and then fall back to the ground.
How is loess related to glaciers?
When glaciers retreat, their meltwater contains loess, which can be picked up by winds and distributed elsewhere.
Which of the following accurately describes the Basin and Range region of the western United States?
a region with alternating mountains and basins that have been produced by normal faulting
A(n) __________ is a cone-shaped deposit of sediment that is deposited when a stream exits the mouth of a canyon.
alluvial fan
What type of rocks would you expect to find in a playa lake depositional environment?
evaporites and claystone
Which one of the following is an evaporite mineral?
gypsum
An isolated, heavily eroded hill or mountain that rises abruptly from a plain is a(n) __________.
inselberg
How do pieces of rock move under the influence of wind?
rolling, sliding, bouncing, suspension
What property of a piece of material will most directly determine how it is carried by wind?
size
What factor limits the depths of blowouts?
the local water table
What is the most important erosional agent in deserts?
water
What is the natural angle of repose for sand?
34 degrees
What is interior drainage?
Interior drainage is when an arid region exhibits a discontinuous pattern of intermittent streams that do not flow out of the desert to the ocean.