Main CERI
Our group is examining the beautiful crossbeds at Red
Rock Canyon. This Jurassic formation is called the Aztec Sandstone,
and was formed around 200 million years ago.
These crossbeds are evidence of the eolian(desert) environment that
existed here in prehistoric time. The
red hues are a result of iron oxides that cement the grains of sand
together.
The most prominent geologic feature of Red
Rock Canyon
is the Keystone Thrust Fault. The fault is difficult to see, but the basic
principle is easy to understand.
The Spring
Mountains are in the left
background, and they are composed of a gray limestone unit that is visible in
this photo. About 65 million years ago
two of the Earth’s crustal plates collided, and in the process thrust the older
paleozoic limestone over the younger Aztec Sandstone.
By Chris Garner
