Quakes much more a concern than a tsunami, experts say Schools & Kids, posted by Editor, Mountain View Voice Online, on Mar 11, 2011 at 2:35 pm
While concern over the possibility of a major earthquake the Bay Area is warranted, an expert from the United States Geological Survey said locals need not fret much about the prospect of a tsunami hitting the Mountain View.
Read the full story here Web Link posted Friday, March 11, 2011, 1:35 PM
Posted by Amazed (but not in a good way), a resident of the Blossom Valley neighborhood, on Mar 14, 2011 at 8:42 am
"Coastal cities are the most at risk from a tsunami, Brocher said. He also said that the Bay Area faults, such as the Hayward and San Andreas, aren't likely to cause a tsunami."
For anyone that actually needed this pointed out to them...unbelievable.
Posted by Mike Rodgers, a resident of the St. Francis Acres neighborhood, on Mar 14, 2011 at 1:27 pm
Actually, Brocher is right with respect to Mountain View. Our greatest risks here are related to the larger local faults, e.g. Hayward fault which is over due for a 7 range quake is an extreme risk for a Kobe or Port Au Prince like quake that would make a direct hit on the east Bay, even with our great resistant building codes, even resilient structures can suffer moderate to heavy damage in a direct hit 7.0 scenario (which might create up to Mercali VIII or IX level ground shaking), ditto for areas immediately above and adjascent to San Andreas (and its 7.9-8.0 potential).
However, we shouldn't lose sight of the fact that slightly to the north of the Bay Area is the Cascadia subduction zone extending from Mendocino to British Columbia which is capable of producing 9 level moment magnitude quakes (& hasn't had a large event since 1700).
One thing to consider is the possibility of much larger tsunamis that could affect the CA coastal communities from a Cascadia event at perhaps 10X the heights and extent inland as was seen this weekend from the Sendai megathrust event (wwhere we had well under 1 meter tsunami here this weekend and yet saw several harbors trashed and ~$100M in damage). Areas well away from the Sendai epicenter in Japan saw large tsunamis, great loss of property and life from up to 4-6 meter tsunamis that struck the north and even west coasts of Honshu and many areas of Hokkaido.