Geology
of California Summer 2000
Robert
Lopez
1)
What
is a desert? What are the three areas
of California characterized as deserts? Name the natural provinces where the
three principle deserts occur in California.
2)
What
causes the deserts in California?
Describe the orographic effect (see fig. 6-2 page 103), and know
which mountain ranges cause the rain shadows for the southern Basin and
Range, Mojave, and Colorado Deserts.
3)
What
happens to ascending air? What happens
to descending air?
4)
What
is desert varnish, and how are petroglyphs related to desert varnish?
5)
What
is desert pavement? Name two possible ways that it is formed.
6)
What
are Intaglios?
7)
What
are Archea?
8)
What
are playas? How are playas formed?
9)
What
three conditions must be met in order to form sand dunes?
10)
What
is alluvium? What is a fan? What is an alluvial fan (see Fig. 6-12 page
111)?
11)
What
are bajadas and how are they formed?
12)
What
are flash floods? What conditions must
occur in order to form flash floods?
13)
Why
were lakes abundant in the Mojave and Basin and Range during the Pleistocene
epoch (even Death Valley was filled by water)?
14)
What
kind of erosional landform is evidence of these Pleistocene lakes (hint, one is
similar to a bathtub ring)?
15)
What
is tufa (not to be confused with tuff)?
What is it composed of and how does it form (see page 116)?
16)
Name
at least two of the sodium borate minerals mined from the California Desert
(page 119).
17)
What
are some of the uses for borate minerals (page 119)?
18)
Name
at least five of California’s Pleistocene Lakes located in the California
Desert (Fig. 6-18, p.115).
19)
What
was the name of the lake that occupied Death Valley? What was the length and depth of this lake?
20)
When
was the last time Owen’s Lake had water in it?
21)
What
is the last surviving Pleistocene Lake in California’s desert – omega lake?