Thursday, July 09, 2009

Hang on to your hard hats!

LOS ANGELES – Scientists have detected a spike in underground rumblings on a section of California's San Andreas Fault that produced a magnitude-7.8 earthquake in 1857.

What these mysterious vibrations say about future earthquakes is far from certain. But some think the deep tremors suggest underground stress may be building up faster than expected and may indicate an increased risk of a major temblor.

Researchers at the University of California, Berkeley, monitored seismic activity on the fault's central section between July 2001 and February 2009 and recorded more than 2,000 tremors. The tremors lasted mere minutes to nearly half an hour.

Unlike earthquakes, tremors occur deeper below the surface and the shaking lasts longer.

During the study period, two strong earthquakes hit — a magnitude-6.5 in 2003 and a magnitude-6.0 a year later. Scientists noticed the frequency of the tremors doubled after the 2003 quake and jumped six-fold after 2004.

Tremor episodes persist today. Though the frequency of tremors have declined since 2004, scientists are still concerned because they are still at a level that is twice as high as before the 2003 quake.

The team also recorded unusually strong rumblings days before the 2004 temblor.

Results of the research appear in Friday's issue of the journal Science. The work was funded by the U.S. Geological Survey and National Science Foundation.

"The fact that the tremors haven't gone down means the time to the next earthquake may come sooner," said Berkeley seismologist and lead researcher Robert Nadeau.

Bottled water, canned food, emergency numbers, camping equipment....

8 comments:

Mike Goldman said...

What about those virgins that were supposed to get laid on the fault? Er, lay on the fault. Whatever.

Ali said...

But prop 8 was passed! You should be safe.

Sorghum Crow said...

Uh-oh. Ahnuld is not going to like this.

ellroon said...

So we need to get our Gropenator to toss non-gay virgins onto the San Andreas fault (don't think we have any active volcanoes at the moment...) .. somehow I don't feel any safer...

/hunkers down with hard hat...

Ali said...

/hunkers down with hard hat...

you'll be OK. It hit China instead.

Of course, that might set off a chain reaction. :)

ellroon said...

And then all the volcanoes in the Pacific Ring of Fire will go off and take out Canada, too. Fair is fair.

Ali said...

and take out Canada, too. Fair is fair.

Well, I live somewhat within the area, but there are no settlements on Mt. Meager or Garibaldi to be taken out. Nice try. :)

ellroon said...

Rats!

But you're right about China.