'Big One' Looms As Quake Swarm Strikes Southern California "In The Worrry Zone"

李居明預測的12月地震月 ?

www.zerohedge.com

Just five months ago, experts warned that "the springs on the San Andreas system have been wound very,
very tight. And the southern San Andreas fault, in particular, looks
like it’s locked, loaded and ready to go." And now, as The LA Times reports, a rapid succession of more than 200 small earthquakes began rupturing near Bombay Beach, at the southern tip of the San Andreas fault, continuing for more than 24 hours.

The temblors were not felt over a very large area, but, as The LA Times continues, they have garnered intense interest — and concern — among seismologists.

It marked only the third time since earthquake sensors were installed there in 1932 that the area had seen such a swarm, and this one had more earthquakes than the events of 2001 and 2009.

The quakes occurred in one of California’s most seismically complex areas. They hit in a seismic zone just south of where the mighty San Andreas fault ends. It is composed of a web of faults that scientists fear could one day wake up the nearby San Andreas from its long slumber.

The San Andreas fault's southernmost stretch has not ruptured since about 1680 — more than 330 years ago, scientists estimate. And a big earthquake happens on average in this area once every 150 or 200 years, so experts think the region is long overdue for a major quake.

The swarm actually increased the likelihood of a much more major quake in Southern California, at least temporarily.

According to the U.S. Geological Survey, for the seven-day period following Tuesday, the chances of a magnitude-7 or greater earthquake being triggered on the southern San Andreas fault are as high as 1 in 100 and as low as 1 in 3,000. The chances diminish over time.

Experts said it’s important to understand that the chance of the swarm triggering a big one, while small, was real.

“This is close enough to be in that worry zone,” seismologist Lucy Jones said of the location of the earthquake swarm. “It’s a part of California that the seismologists all watch.”

on.cc東網專訊

【on.cc東網專訊】 自上周一開始，南加州薩爾頓海（Salton Sea）持續發生不下200次小型地震。雖然強度只達4級，卻引起地震專家強烈興趣和關注，擔心一場大地震會發生在聖安德烈亞斯斷層。

這些地震發生於聖安德烈亞斯斷層末端以南地區，是加州最複雜地震帶之一。科學家擔心，有一天該斷層網會喚醒一直沉睡的聖安德烈亞斯斷層，發生大地震。

聖安德烈亞斯斷層自從1680年以來未曾發生過斷裂，至今已超過330年。該地區平均相隔150至200年就發生一次大地震，因此專家認為，該地區早該發生大地震了。

聖安德烈亞斯斷層在加州最長，也是該州其中一個最危險的斷層。南加州地震中心主心喬丹說，該斷層自1857年起一直「太靜了」。

自從1932年安裝地震傳感器以來，加州總共3次發生持續不斷的群震。最新的群震次數多過2001年和2009年，增強了專家對大地震即將發生的疑心。

美國地質調查局在2008年警告說，7.8級的大地震可能釀成1800人死亡、5萬人受傷，並造成2000億美元的損失。