Week Three: Evidence of Plate Tectonic

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Week Three: Evidence of
Plate Tectonic
• Welcome to Big Cottonwood Canyon!
• According to Utah Geological Survey: “ The Best know fault line in
Utah is the Wasatch Fault, which crosses or passes near the
mouths of the Wasatch Front Canyons.”
The Big Cottonwood Canyons shows great example of tectonic plates
with the use of Thrust Fault-results from compression forces that
shorten and thicken the crust. Movement is horizontal, where older
rock are pushed over younger rocks. Mr.Raymond trust fault trends
through Big Cottonwood Canyon.
Evidence of Thrust Fault in
Utah(Picture and source is Utah
Geological Survey). Location:
Mountain Home Range, Utah.
The second evidence of plate tectonic is
tilted rock layers. • “Tilted rock layers- you can see as you
drive up and down Big Cottonwood
canyon many different examples of
this. You see rock layers that are
straight up and down, where farther up
the canyon they are a little more
slanted, obviously showing that there
has been movement and growth and not
that they are sitting there not moving.”
(Source-Utah Geological Survey)
Tilted Layers of rock, started at
the entrance of the canyon.
Location: 40.6410° N, 111.6890° W
Location: Big Cottonwood Canyon, Utah
40.6410° N, 111.6890° W
Slates and quartzites are exposed in lower Big
Cottonwood canyon at the geologic road sign
"Storm Mountain Quartzites", about 3 miles
from the mouth of the canyon. The black slates
and "rusted"quartzites are part of the Big
Cottonwood Formation, and are about 900
million years old (Source: Hintze, 1988).
The is a spot in Big Cottonwood canyon, 1.5 miles
up on the south side where there is a good showing
of the layers of rock being tilted.
One more example
of layer tilting.
Location: 40.6410°
N, 111.6890° W
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