Well, we're officially way off-topic here... but if the mods don't object, I'll try and clear this up. I now see the problem I was having envisioning rapid mountain uplift. In post 80 you said "there most certainly are forces capable of raising mountains..."
And I didn't have a problem with that statement, I just couldn't believe that a whole range could be uplifted that quickly. Why? Well, mainly because I stupidly forgot about
where and how faults are distributed throughout a given mountain range. (e.g., a typical fault-block range.)
Another reason I kept stumbling over the thought of rapid uplift is because I had my mind fixed on the mistaken notion that mountains were uplifted primarily by way of isostatic adjustment--which, of course, is considerably slower and less dramatic. Anyway, I finally found a paper that describes vertical displacement within a block of the San Gabriel Mountains during the '71 quake.
Preliminary measurements of fault displacements across several traces indicate that the cumulative oblique reverse slip across the 1 km (0.6 mi.) wide zone exceeds 1 m (3 ft.). Left-lateral displacement appears to be smaller than vertical offset throughout most of the fault zone. This indicates that a western block of the San Gabriel Mountains moved south to south-westward and upward relative to the San Fernando Valley block (diagram, page 64).
You can read the entire paper (which is quite interesting, BTW) here:
http://www.johnmartin.com/earthquakes/eqpapers/00000018.htm
Thanks for setting me straight,
--Macavity
P.S. Trixie, thanks for the link.
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