Yes it does, mainly as boulders incorporated into clay debris. It is a sedimentary portion of the old Jalisco Peaks formation that was offshore at the time. The boulder debris is from a large (Amazon size) river that fed into the area. All of this was quite a bit south from the present location, having been dragged north on the west side of the San Andreas Fault at the rate of 4" to 6" per year.
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Yes, some is, some is bedrock, Dood. Here is an interesting link as to why some areas were more badly damaged during the Loma Prieta quake, and other areas almost adjacent, were not:
https://www.exploratorium.edu/faultline/damage/building.html
https://www.exploratorium.edu/faultline/activezone/slides/marina-slide.html
Also detailed in this page, is an interesting concept of resonance. If the building’s natural resonance or sway is in line with the seismic wave resonance, less damage will occur to the building. A lot of very interesting physics going on with seismic activity and subsequent damage.
One of my functions at SDSU was reviewing M.S. Thesis’ in geophysics.
That would have been very cool. My very favorite science classes were physics and geology. I should have been a geologist and not a nurse 
My most favorite field trip ever, was the one I went on in college, in one of my geology classes to Portuguese Bend. Just love the combination of geology and physics, it is endlessly fascinating to me.
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Looks like the southern U.S. is in for a pounding tonight and tomorrow. Meanwhile the chaotic set of low pressure zones in the NW might end up sending more moisture down our way.
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If that low sets up near where its pictured (SE corner of CO) then the CO front range could end up with quite a bit of snow…
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Californians find all sorts of excuses to move to Oregon.
I think it goes both ways, Portland and San Diego seems to have an exchange program
Oroville has dropped from the news, but those 70 ft deep freshly carved canyons in the mountain side (below the emergency spillway) are very worrisome. The regular spillway is now 90% destroyed, with a crater deeper than 100 ft where most of the lower spillway stood. and there is more rain on the way for Northern CA.
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It seems to me that the Army Corps of Engineers has never really understood the cost of ownership.
On basements, I was told the reason you do not see them in the south is they are not needed. They need them up north due to the soil freezing several feet. They have to have the pipes deep in the ground to keep them from freezing. In Texas water pipelines are usually only 18 inches in the ground. That is all that is needed to keep them from freezing. It is much cheaper to build flat or 2 story than it would be to excavate several feet of soil.
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That’s the building code in the California counties I’ve lived in.
Yes my water pipes are 10’ down.
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A lot of flooding in the San Francisco Bay area and north San Joaquin Valley late yesterday and today, many roads closed, and some neighborhoods under water.
http://time.com/4677567/california-weather-flooding-rescue-san-jose/
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Ya know, that portion of San Jose was built on an intermediate flood plane. My cousin lives a bit upstream and to the east on higher ground.