Posted on 05/21/2008 1:46:22 PM PDT by blam
Calif. quake scientists detail impact of 'Big One'
By ALICIA CHANG, AP Science Writer
May 21, 2008
In this Jan. 17, 1994, file photo, the covered body of Los Angeles motorcycle officer Clarence W. Dean lays near his motorcycle which plunged off Highway 14 overpass that collapsed onto Interstate 5 in the San Fernando Valley section of Los Angeles. In a joint publication, to be released Thursday, May 22, 2008, of the U.S. Geological Survey and California Geological Survey, scientists for the first time have written a script detailing the devastation California would likely face if it were rocked by a monstrous 7.8-magnitude earthquake. (AP Photo/Doug Pizac)
(AP) -- The "Big One," as earthquake scientists imagine it in a detailed, first-of-its-kind script, unzips California's mighty San Andreas Fault north of the Mexican border. In less than two minutes, Los Angeles and its sprawling suburbs are shaking like a bowl of jelly.
The jolt from the 7.8-magnitude temblor lasts for three minutes - 15 times longer than the disastrous 1994 Northridge quake.
Water and sewer pipes crack. Power fails. Part of major highways break. Some high-rise steel frame buildings and older concrete and brick structures collapse.
Hospitals are swamped with 50,000 injured as all of Southern California reels from a blow on par with the Sept. 11 attacks and Hurricane Katrina: $200 billion in damage to the economy, and 1,800 dead.
Only about 700 of those people are victims of building collapses. Many others are lost to the 1,600 fires burning across the region - too many for firefighters to tackle at once.
A team of about 300 scientists, governments, first responders and industries worked for more than a year to create a realistic crisis scenario that can be used for preparedness, including a statewide drill planned later this year. Published by the U.S. Geological Survey and California Geological Survey, it is to be released Thursday in Washington, D.C.
Researchers caution that it is not a prediction, but the possibility of a major California quake in the next few decades is very real.
Last month, the USGS reported that the Golden State has a 46 percent chance of a 7.5 or larger quake in the next 30 years, and that such a quake probably would hit Southern California. The Northridge quake, which killed 72 people and caused $25 billion in damage, was much smaller at magnitude 6.7.
"We cannot keep on planning for Northridge," said USGS seismologist Lucy Jones. "The science tells that it's not the worst we're going to face."
USGS geophysicist Kenneth Hudnut said scientists wanted to create a plausible narrative and avoided science fiction like the 2004 TV miniseries "10.5" about an Armageddon quake on the West Coast.
"We didn't want to stretch credibility," said Hudnut. "We didn't want to make it a worst-case scenario, but one that would have major consequences."
The figures are based on the assumption that the state takes no continued action to retrofit flimsy buildings or update emergency plans. The projected loss is far less than the magnitude-7.9 killer that caused more than 40,000 deaths last week in western China, in part because California has stricter building code enforcement and retrofit programs.
The scenario is focused on the San Andreas Fault, the 800-mile boundary where the Pacific and North American plates grind against each other. The fault is the source of some of the largest earthquakes in state history, including the monstrous magnitude-7.8 quake that reduced San Francisco to ashes and killed 3,000 people in 1906.
In imagining the next "Big One," scientists considered the section of the San Andreas loaded with the most stored energy and the most primed to break. Most agree it's the southernmost segment, which has not popped since 1690, when it unleashed an estimated 7.7 jolt.
Scientists chose the parameters of the fictional temblor such as its size and length of rupture and ran computer models to simulate ground movement. Engineers calculated the effects of shaking on freeways, buildings, pipelines and other infrastructure. Risk analysts used the data to estimate casualties and damages.
A real quake would yield different results from the scenario, which excludes possibilities such as fierce Santa Ana winds that could whip fires into infernos.
The scenario: The San Andreas Fault suddenly rumbles to life on Nov. 13, 2008, just after morning rush hour. The quake begins north of the U.S.-Mexican border near the Salton Sea and the fault ruptures for about 200 miles in a northwest direction ending near the high desert town of Palmdale about 40 miles north of downtown Los Angeles.
Scientists chose the scenario because it would create intense shaking in the Los Angeles Basin and neighboring counties - a region with nearly 22 million people.
The scenario will be released at a House Subcommittee on Energy and Mineral Resources meeting in Washington.
Here are the major elements:
-10 a.m.: The San Andreas Fault ruptures, sending shock waves racing at 2 miles per second.
-30 seconds later: The agricultural Coachella Valley shakes first. Older buildings crumble. Fires start. Sections of Interstate 10, one of the nation's major east-west corridors, break apart.
-1 minute later: Interstate 15, a key north-south route, is severed in places. Rail lines break; a train derails. Tremors hit burgeoning Riverside and San Bernardino counties east of Los Angeles.
-1 minute, 30 seconds later: Shock waves advance toward the Los Angeles Basin, shaking it violently for 55 seconds.
-2 minutes later: The rupture stops near Palmdale, but waves march north toward coastal Santa Barbara and into the Central Valley city of Bakersfield.
-30 minutes later: Emergency responders begin to fan across the region. A magnitude-7 aftershock hits, but sends its energy south into Mexico. Several more big aftershocks will hit in following days and months.
Major fires following the quake would cause the most damage, said Keith Porter, of the University of Colorado, Boulder, who studied physical damage for the scenario.
The quake would likely spark 1,600 fires that would destroy 200 million square feet of housing and residential properties worth between $40 billion and $100 billion, according to the scenario.
Once the shaking stops, emergency responders would do a "windshield survey" that involves rolling through neighborhoods to tally damage and identify areas of greatest need, said Larry Collins, captain of the Urban Search & Rescue Task Force at the Los Angeles County Fire Department.
Collins said the scale of the disaster means firefighters would not be able to put out every flame.
"We're going to have to think about out-of-the-box solutions," he said.
Illegals: you’ve been warned. Go home now before the quake hits!
Why did they have to choose the day before I turn 40?????
Not addressed: Will the traffic on Highway 91 get any worse?
I always wondered if the 1968 in you name was your birth year. My son was born in 1968 too. He was forty in Feburary.
Also, I used to have a technician name Johnny Rios who signed his initials 'JRios' too.
Technically speaking, I think that there is a more dangerous fault than the San Andreas in the area. It starts in the LA area and heads East, through Palm Springs.
What I heard years ago what that unlike the San Andreas, that goes off at intervals, this fault has been building up a lot of energy, and when it goes, could about flatten LA and Palm Springs.
“The southern section of the fault, which crosses through Palm Springs and San Bernardino, has not experienced a major earthquake in at least 300 years, according to Yuri Fialko of the Scripps Institution of Oceanography at the University of California, San Diego.
As a result, the fault has been stressed to a level where it could unleash an earthquake with a magnitude of seven or greater. The fault marks the intersection where the Pacific plate meets the North American plate.
The fault-slip rate, or pace of the plate movement at the fault, is about one inch per year. But pressure buildup indicates that the southern region of the fault has accumulated 6 to 8 meters of slip deficit—that is, movement that should have occurred but hasn’t because the plates have temporarily become stuck against each other—which inevitably will be released in future earthquakes.”
They would just think it was Fiesta.
This was the scenario that given at my ex-brother-in-laws graduation ceremony for his Fire Department Paramedics class in 1985. We were told citizens on a whole will be left on our own when the Big One hits. I wondered why
this was the first time I had heard this after living
my whole life In So Cal. I took a EMT class at our Local Jr.College and heard from L.A. County Paramedics some
more scary facts. I am determined to be prepared for my family and neighbors. I pray it will be enough.
I forgot, There will be RIOTS LIKE WE HAVE NEVER SEEN BEFORE! Get Guns, Amno and get licensed.
You know it won't be; but by preparing you stand a very good chance of handling whatever is dealt you. The hard part will be your desire to help others; and what you can humanly do.
Has anyone heard of companies here in CA having emergency provisions and supplies stocked on location in case of the big one in case some people can’t get home. I’ve heard talk of my employer do so, but it hasnt happened yet. Just curious...
damn
damn.
Kern County, 1952
This deep quake was among the largest in Southern California, causing widespread damage with over 20 aftershocks.
Magnitude: 7.7
Deaths: 12
Injuries: 18
Damage: $50 million
Three years, huh? I coulda done it in a few minutes:
"A magnitude 7.8 earthquake hits. Things shake, break and burn. Lots of people are hurt and killed. Send help."
Where's my grant money?
And the porn industry suffers a minor setback
nObama is everywhere... 
working for peace!
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