Monday, October 31, 2016

Simple Fault Mechanics - Strike-Slip



In California, this is the 'be-all-and-end-all' of faulting.  This is what started fault mechanics in 1906, and gave rise to the sacred 'elastic rebound theory'.  I read the whole 1906 report (bible) that founded the busgus (USGS).  In the diagram, the view is from the top.  This is so religious that they always refer to a surface fault 'causing' an earthquake, and every time they map a new one, they increase the seismic hazard.  Fools.

We have these East of the Rocky Mountains, Eastern North America (ENA), but they never break the surface, and are always complex.  They generally combine a thrust component, and are the common faulting situation for single shots such as Virginia.  This is the type of faulting that will destroy Toronto.

They are particularly deadly because they always have directivity to the NE and also because of the thrust component.  The New Madrid sequence had one of these, and two thrusts because it was complex mechanism, just like OK.  Toronto will only have one.

End of series.

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