Hey John and everyone else...I've been asking the question for years about what drives the giant post-5 million year anticlines in the southern California Outer Borderland...extending from Santa Rosa Island SSE to San Nicolas Island and Cortes Bank and beyond...there is rapid strain accumulation under/near Los Angeles from GPS....but unclear what structures are responsible for that. In the high Himalaya the GPS shows 25 mm/yr strain accumulation...but the active faults at the surface that take up all that motion are >100 km south (JGR paper with French authors). Davis and Namson 1994 in a NEHRP technical report interpret all the big offshore folds to be above giant low-angle fault system rooted beneath San Andreas. There is very little seismicity in outer Borderland...so not creeping out there. Why not have this mega thrust system existm creeping near LA, locked farther out....folding occurs during giant earthquakes. Despite my comments at workshop(s), this possibility is not considered in hazard evaulations for SOCAL. Instead, there are kinematically unrealistic patches or ramps here and there, where the work has been done....
Chris