On Apr 15, 2:20*pm, bpnjensen wrote:
On Apr 15, 6:25*am, dave wrote:

On 04/14/2011 03:04 PM, bpnjensen wrote:

Being in a seismically active area is not quite the same as being on a
fault line. *Fault rupture is, at any given time, a more serious issue
to local buildings than the ensuing ground shaking - it will break
your structure in two; but if you are not on a fault line, then
shaking is your key problem if you are not in danger of a landslide,
tsunami or liquefaction. *A building can be built to withstand almost
any foreseeable level of shake.

Surface cracking is localized. It is not the actual fault opening up.
EQs occur a mile or more below the surface.

Correct, but you may want to come up to the Bay Area and see what has
happened at Point Reyes, Los Trancos and elsewhere. *It may be surface
cracking, but the ground does open up, and the two sides exhibit
significant displacement in three dimensions. *Whether it is the
actual fault is immaterial - it will disassemble structures. *I'm sure
you guys have examples in SoCal, and there are some seriously
spectacular scarps in Nevada and down near Carrizo Plain, if I'm not
mistaken.

Absolutely and positively : True . Entire villages/settlements are
known to have disappeared during such seismic activity . No structure
is safe under these extreme conditions .