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Introduction to Desert Geology
Geology
All three families of rock
are evident in the Mojave Desert —
igneous,
sedimentary, and metamorphic. The earliest rock, related to the metamorphic
gneiss and schist at the bottom of the Grand Canyon, has little exposure in
the Mojave, but can be seen at Saddle Island in
Lake Mead National Recreation
Area (NRA) and parts of
Death Valley National Park
(NP). Changed from preexisting
rock by immense temperature
and/or pressure (without melting), this
metamorphic
rock is ancient — from the
Precambrian Era, formed about 1.6 to 1.8
billion years ago.
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Introduction
Geology
Once Upon A Time
Magma On The Move
Shake, Rattle, And Roll
Whittling The Earth
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