imaging of nearshore Santa Monica fault available
Posted by heartland chris on December 09, 2006 at 21:51:54:

My paper on the Santa Monica-Dume fault came out in November, and a week or so ago I found out that a bunch of deep acoustic imaging (seismic reflection data) of Santa Monica Bay had become available; I had been waiting for these. We had no data for the 10 km west of where the fault heads offshore at Potrero canyon, and sparse and not very good data for another 10 km...so we just interpolated (joined) what we mapped offshore to onshore. Now, I could take a shot at mapping that part of the fault directly. It might only take a week, with all digital data and fancy software. But, I most likely will not do this for some time....the blind faults underneath Palos Verdes/San Pedro Shelf/Shelf Projection are more unknown and it is these that I need to work on.
It may well be important to map that part of the fault directly, because the geometry there may bear on how likely it is that the whole onshore-offshore fault could break as a M7 right down Santa Monica Blvd (e.g., Dolan et al., 2000), or if it might be stopped at a bend or stepover just offshore, and break in 2 smaller quakes instead. This bears on strong ground motion and tall buildings.

When I worked for an oil company in the early 80s I just mapped away, 8 hours day, 50 weeks a year. Now, even though I don't teach, everything is more complicated and it can take months to free up a week to do something like that..
the snows melting here in the heartland...I'll get my last quick ski around the park tomorrow morning.
Chris