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College of Physical and Mathematical Sciences
Department of Geological Sciences

Tool Marks and Fault Core Zone

Tool Marks

Tool-and-pen.jpeg

(Photo by Bill Harris)

The tool marks at the Seven Peaks Scarp show good evidence of movement along the Wasatch Fault. Notice the slightly different direction of the various scratches. This indicates a somewhat oblique movement of the hanging wall of the fault during an earthquake event.

Fault Core Zone

Core-and-damage.jpeg

(Photo by Bill Harris)

The core zone of the fault is the tightly cemented material on the wall of the fault.  As the rocks move along the fault they are crushed, shattered, and sheared.  This pulverized material is recemented together as water moves through along the fault carrying dissolved calcite.  The recemented material is very impermeable to the movement of water through the fault.

The damage zone is composed of larger, broken fragments, is also very impermeable.  Permeability tests of this site showed both the core and damage zone as being a barrier for any water movement through the fault.

Wasatch Fault Menu

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