This is the basic geology that contributes to earthquakes in Utah.
These are the major ways the earth's crustal plates move in relation to each other.
Utah's earthquakes are a result of Continental Collision movement. This generates tremendous force, resulting in the UPTHRUST of the mountains so visible along the Wasatch Front.
California primarily experiences TRANSFORM movement along its San Andreas Fault.
Seattle experiences SUBDUCTION earthquakes along its Cascadia Fault Zone.
DIVERGENT earthquakes occur in the depths of the ocean.
Harpers Corner, located in Dinosaur National Monument and on the southwest flank of the Uinta Mountains, is an impressive example of UPTHRUST or UPLIFT.
Here, movement in the crustal plate pushed up from the bottom, and squeezed from the sides, warping and lifting the earth's crust to create awe-inspiring vistas.
This illustrates the complex geology that forms the Wasatch Fault Zone.
A SIGNIFICANT BOTTOM LINE
These colored lines represent the locations of known faults along the Wasatch Front. The darker the line (the redder it is), the higher the probability of a major earthquake occurring in the next 50 years (2014-2063).
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