A post! This time with content.

So everyone has heard about the multiple moderate to large earthquakes happening in and around california. A 5.6, a 7.2 and a 5.3 have all occured within the last week, the 5.6 and 5.3 have both been quite close to me while the 7.2 (luckily) was located waaay up north and about 140 km west of Crescent City. This has brought up the question "is the Big One coming?" WELL, to get an answer for that, I e-mailed my old geology professor from USC to see what he thought about the current situation.

My e-mail to him (edited down for size):

Professor Dolan,

My question is: Do you see the two recent earthquakes outside the Los
Angeles area as possible precursors to "the big one." I remember from
class you said that historical records show a large earthquake in this area is overdue and that large earthquakes are preceded by chains of smaller
earthquakes that gradually build up. So if we see a 6.0 soon in the
future and possibly a 7.0 do you think it is very likely an 8.0 or
larger will hit?

His response:

Hi Daniel,

Cool question. Unfortunately, neither I (nor anybody else :-)) knows
the answer right now. Seismologists are recently much more accepting
of the possibility of very long-term and long-distance interactions
between earthquakes. I think many of them are just starting to take
these ideas seriously. But the jury is still out on "global-scale"
interactions whereby an earthquake in Chile say, could influence the
occurrence of a Big One in Japan (or here). we just don't know yet.
This Mw 5.3 that just happened a bit ago and the 5.6 the other day
both occurred on two big fautls. The San Andreas and San Jacinto,
respectively, so this is cause for some curiosity, if not immediate
concern. Remember that about 5% of all earthquakes are foreshocks to
something larger. Keep your fingers crossed that these are in the
other 95%.

Thanks for the quick response, Professor Dolan.

First, he admits that he doesn't know the answer, which is fine. Earthquakes have always been near impossible to predict and authorities in the field are reluctant to claim one is going to happen so they don't cause undue stress to people that hear their prediction and take it as the gospel.

Next, the 5% of all earthquakes are foreshocks to something larger was interesting, I hadn't heard that before. So I guess we have a 5% chance of getting a larger one soon. Neat!

Another thing I hadn't heard before was the "global-scale" of interactions between earthquakes. Could a Big One in Japan trigger or prevent a big one in California? Or vice versa.

Long story short I suppose his answer to my question was: We have a 5% chance of something larger coming. Will that be the "Big One?" No one knows.

Earthquakes are an elusive beast. And I'm a huge nerd.

DANCREST OUT.