Surviving the initial event

[NorthernRaider]

Quakes length of time are one point, but not the most important, it is the depth of the P & S waves from the surface and the frequency / severity of them that cause the most problems, EG The 9 pointer off Fukshima lasted over 9 minutes in places and was just under the surface causing huge displacement. The Indian ocean quake was a similat long lasting event. But a quake in the Turkey / Stans area a few years ago only lasted about 40 seconds and still levelled entire cities.

Cross the pond to the US / Mexico and some quakes tremble and grumble away for hours before letting rip but they are so deep the effect on the surface is negligable.

If much of the fault line that runs from Alaska to Baja let go the way it has in the distant past the effects are going to be instantanious like the Alasks quake of 64 when some place rose 40 ft in second and others fell, with localised tsunamis in some places sloshing over 300 feet up the side of a valley.

Quakes are relative and your point valid and welcome