Liquification scares me.
Isn't San Francisco's Nob Hill solid rock?
I'm just up the peninsula from Sili Valley. Glad my apartment complex and office building have been around a while, but I haven't gone through a 'big one' yet, just a few rollers.
"Solid rock" in the Bay Area means the bedrock that you use to support a building if you want to minimize earthquake damage. What you call "shattered rock" doesn't move much in an earthquake and is essentially "solid" for earthquake purposes unless it is right on a fault. Marin County, where I lived, sustained very little damage during the 1989 Loma Prieta quake because almost all of the buildings have their foundations tied into what you are calling "shattered" rock.
The buildings and structures in the Bay Area that suffered 99.9% of the Loam Prieta damage were poorly constructed on Bay mud or fill and were either not tied into what you call "shattered rock" and/or not built with sufficient lateral support. Prime examples are the old Marina houses, the Bay bridge, and the Cypress Freeway.
...many areas in the south bay near the waters edge have hundreds of feet of topsoil above their rock layers, so anchoring is only done on the newer larger buildings.
If by "newer" you mean built or retrofitted in the last 30-40 years you would may be correct.
Just one of the many reasons I no longer work in the Silicon Valley.
Chicken. (Just kidding.)
After the '89 Loma Prieta quake (M7.1) I was riding my bike on the bike path along the Redwood Shores - Foster City waterfront and lo and behold, I found one instance of sand volcanos in the high intertidal zone, just off of one of the levees. They dodged a bullet that time around along the bayshore. Imagine what is possible.