When we lived in So. Cal we were nearly equidistant between the San Andreas and San Jacinto faults, 4 miles from the San Jacinto, 5 from the San Andreas. Talk about your earthquake probability. One day we had a quake centered directly underneath our house. It was, thankfully, only about a 2.3 or 2.4, I can't remember which, but it was memorable! There was a deafening CRACK, simultaneous hard jolt, (only one, not a continuous shaking), an overpowering smell of sulfur, and the water in the pool turned into a tsunami, walls of water sloshing out first at one end, then the other. Interesting. People a block away didn't even feel it.