Dr-LucyJones

The Japanese have shown that you can safely operate hi speed rail with earthquakes if you have earthquake early warning systems. No trains derailed in the 2011 M9 because no trains were moving when the strong shaking got to them.

"Richter Scale" used a very particular type of seismogram. "Magnitude" can be one of many different ways to determine the innate size of the earthquake. The most reliable now is "Moment magnitude" that processes the complete seismogram for the best picture of the total energy.

Neither of these is what you feel in an earthquake. That is described by "Intensity", usually the Modified Mercalli Intensity scale. . Because the shaking varies from place to place in a given earthquake, the intensity does to

Yes, earthquake triggering is very realistic. A Hayward fault earthquake after a San Andreas quake would just be considered an aftershock - like the Big Bear aftershock to the Landers earthquake.

We also see triggered earthquakes at greater distances where we don't use the word "aftershock" but they are still related. In the day after the great 1906 earthquake that devastated San Francisco, we saw a M6.0 in Imperial County and a M5 in Santa Monica Bay

"California falling into the ocean" - the ocean is not a hole. It is land with a lower elevation "We have good building codes so we must have good buildings". Building codes aren't retroactive so your building is as good as the building code in place when it was built. Also, our building codes are life-safety only - make sure you can crawl out alive

If the whole southern section goes in one earthquake, that would 8.2 to 8.3