A 7.0 Earthquake Shakes Pacific Northwest. Does it seem to you that newsworthy earthquakes seem to hit disparate places on the globe in clusters? Within the month, we’ve seen the Gujarat quake, the El Salvador quake, and now this. Is this a geophysical clustering or a sampling effect of what the media pay attention to? In related news, researchers studying the magnitude-7.7 Indian quake now say that faults beneath California’s populous areas “could
produce larger earthquakes than
previously thought… The type of fault that produced the deadly Jan. 26 quake – a
blind thrust fault – is also found in California, including at least
one running directly beneath the skyscrapers of downtown Los
Angeles.” Blind thrust faults are difficult to map because they do not break the surface. Earlier estimates capped the potential force of a blind thrust quake in California at not much more than the 1989 San Francisco earthquake or the 1994 Northridge quake, but the researchers are revising their estimates considerably upward after looking at Gujarat.