Liquifaction

Given strong shaking over a given minimum short time certain soils will turn to a liquid. This is called liquefaction. The looser and the smaller the particles the more effect. Sand would be worse. Bed rock will not liquefy. Hard dry clay is probable that it will, but is still to some degree questionable in my mind. Once the soil is in a liquid form it will slosh like any other liquid. I am sure at some places on this planet we could have quite high waves of sloshing soil that cover and engulf objects. This is one of the whys behind not building underground or putting wells and other objects underground without some best guess at the effects of liquefaction for the area.

My best guess at this time is if the soil is good enough to grow in, it will most probably liquefy and depending on how long the shaking last could get quite stirred up. The landscape around you would change. Also any shelter built on this would need to float slide and ride the waves and right it's self due to a properly designed low center of gravity. The good news is the heavy duty shaking and hurricane winds is estimated to last less than one hour. One more thing to know - just as a boat will sink until it displaces it's own weight in water - so will it be with all things lighter than the liquid soil. So with this you can predict after the shaking stops, how much will be above ground for your survival quarters.

Offered by Mike.

Just as a further example of liquefaction, look at the Alaskan 64 earthquake and Anchorage. Anchorage is built on silt basically. During the earthquake and when things were shaking, some of the buildings there settled into the ground due to liquefaction and a term called "thicksotropic". Think of a bottle of catsup that has been sitting in the fridge. It has a small layer over the top, causing great concern for many a diner on "I can't get this stupid catsup out of the bottle!". You could lay a penny on top of catsup and it will stay there on top. But, if you shake that bottle (simulated earthquake) the penny sinks and is thrown around and buried because that top layer of the catsup is broken. That is liquefaction. And, since we are here, just shake your catsup bottle next time before you pour it, then it will come out.

Offered by Clipper.