USGS - science for a changing world

Pacific Coastal & Marine Science Center

Coastal and Marine Earthquake Studies


The Cascadia Megathrust and Tectonic Stress in the Pacific Northwest

Stress and Faulting (in an ideal world)

If one of the principal stresses is vertical, then the principal stresses can be related to one of three basic fault types:

Reverse, Normal, Strike-Slip Faults

If one of the principal stresses is not vertical, then the style of faulting will be a hybrid of strike-slip faulting and either reverse (thrust) or normal faulting.