En Español
Send Us Feedback
News Video

Find, view and share videos about news and entertainment from around the Web.
See Videos »
most

POPULAR

stories
most

COMMENTED

stories
most

RECENT

comments

News Alerts

The latest updates sent straight to your inbox.

Get AOL News Alerts »

San Andreas Fault Longer Than Thought

LiveScience
Robin Lloyd
,
LiveScience
posted: 75 DAYS 8 HOURS AGO
comments: 113
filed under: National News, Science News
PrintShare
Text SizeAAA
LiveScience.com
(July 30) - As if the San Andreas Fault weren't long and menacing enough, newly found mud pots and mud volcanoes now suggest it extends another 18 miles, going under the Salton Sea and beyond, in the desert southeast of Palm Springs.

California's Earthquake Source

San Andreas fault line - mapCassandra Shie, AOL

The San Andreas Fault line, which runs roughly 700 miles through California's west coast, is longer than previously thought, researchers found. The line, which separates different plates of land that move in different directions and cause earthquakes, extends another 18 miles in the desert southeast of Palm Springs.

1 of 4PHOTOS

AOL News

X | Close
The extension is probably inactive.
U.S. Geological Survey researchers David K. Lynch and Kenneth W. Hudnut report this result after a survey of mud pots in the area immediately east of the southeastern-most portion of the Salton Sea in Imperial County, Calif.
Using satellite imagery and a physical examination of the land, they identified a cluster of 33 mud pots, mud volcanoes and sink holes which, when plotted, form a clear linear pattern that suggests an underground rift or fault.
"The presence of a linear field of geothermal features is evidence of a planar rift extending to considerable depth in the crust," Lynch and Hudnut write in the August issue of the Bulletin of the Seismological Society of America.
Mud pots and mud volcanoes are features produced when water or gas is forced upward through soil and sediments. Mud pots are typically depressions or enclosed basins containing gas seeps, bubbling water or viscous mud. Mud pots can also be water-laden and appear as bubbling muddy water.
Mud volcanoes, on the other hand, are elevated conical structures composed of accumulations of viscous mud extruded from a central vent. They range from finger-sized to several miles across, though the largest in the Salton Sea area are about 6 feet (2 meters) high. Small mud volcanoes on land, ranging from one to 10 feet in height, are usually called mud cones or gryphons and are usually associated with volcanic and seismic activity.
"Water and gas (CO2 mostly) coming up from below the surface must have a source," Lynch explained. "It is usually associated with an opening in the crust that reaches down to a magma body relatively close to the surface (like Yellowstone). The fact that [the mud pots and mud volcanoes] line up indicates a fault. The fact that they line up with the end of the San Andreas Fault suggests that the two are connected somehow."
Lynch said he was "very surprised" to find that the mud pots line-up. "I was not looking for a fault. I was simply studying the mud pots," he told LiveScience. "When I noticed the alignment, I knew it meant something, probably a fault. A few days later, I plotted up the pots and noticed that they lined up with the accepted end of the San Andreas Fault. That's when I got excited and contacted Ken Hudnut."
FEED

More from LiveScience

More Stories
Geologists had suspected that the San Andreas Fault extended beyond its agreed-upon terminal point near Bombay Beach, a location about midway along the eastern shore of the Salton Sea, but no one had previously had found any evidence at the surface, Lynch said. Erosion, seismic inactivity and agriculture erased any previously identifiable evidence.
The Salton Sea is an extremely salty, below-sea-level lake and the largest lake in California. It formed starting in 1905 when rainfall forced the Colorado River to swell and breach a nearby dike. The town of Salton and some Indian land was submerged by the time the flooding was controlled, two years later. Today, the lake, which supports diverse birds migrating along the West Coast, is fed mostly by agricultural run-off flowing into nearby rivers.
The San Andreas Fault is a 700-mile plate boundary in California, separating the Pacific and North American plates. Seismologists say that enough stress has accumulated at the fault to generate the next "Big One," an earthquake of magnitude 7.0 or greater, any day now or 10 years or more from now. Southern California is at greatest risk because there has been no big quake there along the San Andreas in more than 250 years, said Yuri Fialko at the Scripps Institution of Oceanography at the University of California, San Diego.
Lynch said the new evidence of the San Andreas extension indicates that the region is more complicated than researchers previously thought.
"The extension of the San Andreas does not appear to be active. It is probably a very old part of the fault, and helps to explain the larger, more complex transition area between the Imperial fault and San Andreas Fault, called the Brawley Seismic Zone," he said.
© Imaginova Corp. All rights reserved.
2008-07-30 10:07:02
GOOD READ?
79 votes
(113)
Sort by:

1 - 10

Karl71

06:15 AMAug 10 2008

Boy i couldn't begin to guess how much money that would cost us as a whole if Califorina was destoryed. If I was a researcher I would be locating every fault line which could cost thousands of people their lives if they are not found and when they let lose.

AVG RATING:
(0)

Adamkwyhmed

05:03 AMAug 08 2008

If financial, (finances set aside for the next one), and physical preperation, (reinforcement of both natural and man-made structures), is made by the Californian government now, than, the next "big one" will not make as much of an impact if they weren't prepared. People are still going to be hurt, but the cost of human lives should decrease due to the Governmental preperation for the "big one".

AVG RATING:
(0)

RJOLLY21

09:50 AMAug 01 2008

pbc444 That's because it's the liberal home base!!

AVG RATING:
(0)

ZoloftNotWorking

05:34 PMJul 31 2008

The San Andreas fault is moving at the rate of a vaey few inches a year. I don't remember the exact number off the toop of my head, but I'm sure it's less than 4" per year. A rough calculation using a linear distance between San Francisco and Los Angeles of 400 miles (a guess) and 4" a year of movement gives a time of about 6 million years before the two cities can shake hands and argue over property rights!

AVG RATING:
(1)

PBJPLZMOM

05:29 PMJul 31 2008

What amazes me is all the igits that want Cali to be wiped out...hello I guess that means you can give a rats patoot for all the innocent people that would die from it too? Look back at all the natural disasters that have happened and I am thankful that there are at least some people that care about life and try and do help out those in need and I don't care where you are from and the disaster happens, I am just glad that the world isn't totally ful of igits.

AVG RATING:
(3)

DKandMP

02:49 PMJul 31 2008

The San Andreas Fault is where the Pacific and North American Plates meet. The Pacific Plate is moving towards the NW. Eventually, in about 10,000 years, Los Angeles and San Fransisco will be next door neighbors. There WILL be a large earthquake along this fault in the future. The PROBABILITY is high that the southern portion of the fault will be likely to experience a large eq. Yes, there are other places in the country that could have large eq's. The New Madrid Fault Line produced one of THE largest eq's ever in this country. However, California, Washington, and Oregon experience MORE earthquakes than do other parts of the US. We just had a 5.4 here in Cali on Tuesday.

AVG RATING:
(3)

PBC444

11:28 AMJul 31 2008

LOL, what is interesting is that so many take note of Cali in regard to earthwuakes and remain oblvious to the fact that there are other earthquake zones and some actually considered far more hazardous even in the midwest or along the east coast and that too do indeed have quakes...Cali gets the major attention for it , but others are vulnerable and more likely to find folks TOTALLY unprepared in an aftermath of such a seismic event !!!

AVG RATING:
(2)

TillLarsen

11:01 AMJul 31 2008

The age old question comes to mind, does size really matter? Since the 1970's I have been hearing how this fault is ready to create a major earth changing earthquake! Could it happen (yes), will it happen during our life time ( who knows)!

AVG RATING:
(1)

LokisMommy1

10:54 AMJul 31 2008

Some here need to go back to Geology class.

AVG RATING:
(1)

Gman350z

10:36 AMJul 31 2008

I'm sure if some lawyer can figure out who's FAULT it is they will try to sue them as long as their pockets are deep! Semper Fi

AVG RATING:
(1)

1 - 10 of 113

{ JOIN the CONVERSATION }

YOU'LL BE ASKED TO REGISTER OR LOGIN BEFORE POSTING A COMMENT.

News Makers

NewsmakersBig Brown, the horse that won the Kentucky Derby and Preakness, suffers a career-ending injury.1 of 7

News Makers