Earthquakes in the Brawley Seismic Zone: Updated 09/30/2016
The swarm includes 96 earthquakes above magnitude 2 so far (as of 12:00 pm PDT on Sept. 30, 2016). Relocations of these events show that they are occurring in the depth range 4 to 9 km. The largest of these events were two M4.3 earthquakes and a M4.1 earthquake on Sept. 26.
The earthquakes are occurring near a set of north-northeast trending cross-faults beneath the Salton Sea. The cross-faults are part of a fault network that connect the southernmost end of the San Andreas Fault with the Imperial Fault. Some of the cross-faults are oriented such that they add stress to the San Andreas Fault and the San Jacinto Fault system when they rupture in small earthquakes like those in the ongoing swarm.
Swarm-like activity in this region has occurred in the past, so this week’s activity, in and of itself, is not necessarily cause for alarm.
Preliminary calculations indicate that, as of 12:00 pm (PDT) on Sept. 30, 2016, there is 0.006% to 0.2% chance (less than 1 in 10,000 to 1 in 500) of a magnitude 7 or greater earthquake being triggered on the Southern San Andreas Fault within the next seven days through October 7, with the likelihood decreasing over time. This range is estimated using several models developed in California to assess foreshock/aftershock probabilities, and the lower bound is about equal to the average chance of a magnitude 7 earthquake occurring on the Southern San Andreas Fault in any given week.
These revised probabilities are lower than those made earlier this week, due to decreasing swarm activity. The probabilities may change if the swarm activity increases or decreases.
The Patriot Conservative News Tea Party Network
liberalism + Socialism = Terrorism
Thanks for your Support
The Los Angeles Times
San Andreas fault 'locked, loaded and ready to roll' with big earthquake, expert says.
Southern California’s section of the San Andreas fault is “locked, loaded and ready to roll,” a leading earthquake scientist said Wednesday at the National Earthquake Conference in Long Beach.
The San Andreas fault is one of California’s most dangerous, and is the state’s longest fault. Yet for Southern California, the last big earthquake to strike the southern San Andreas was in 1857, when a magnitude 7.9 earthquake ruptured an astonishing 185 miles between Monterey County and the San Gabriel Mountains near Los Angeles.It has been quiet since then — too quiet, said Thomas Jordan, director of the Southern California Earthquake Center.
Northern California rocked by magnitude 6.0 earthquake
A magnitude 6.0 earthquake hit Northern California near Napa Valley Sunday, injuring at least 120 — 3 critically — and causing extensive damage, including fires sparked by burst gas lines, in the largest tremor to rock the Bay Area since the magnitude 6.9 Loma Prieta quake in 1989.
Leslie Gordon of the U.S. Geological Survey says the tremor struck just before 3:30 a.m. Sunday local time, about 10 miles northwest of American Canyon, which is about 6 miles southwest of Napa.
The city of Napa said in a statement Sunday that two adults and one child have critical injuries, and Queen of the Valley hospital in Napa reported treating 120 people. Hospital spokeswoman Vanessa DeGier says most patients have cuts, bumps and bruises.
Three people were admitted with broken bones and two for heart attacks, according to The Associated Press.
Napa City Manager Mike Parness said the city declared a local emergency at 8:59 a.m. California time, which is the first step in getting more help from the state.
Parness said during a news conference Sunday evening that about 11,000-14,000 households of 80,000 in the quake zone were without power and that authorities hoped to have all power restored by Monday.
Mark Ghilarducci, director of the California Governor's Office of Emergency Services, said
about 90 to 100 homes were deemed not habitable. He said the next step was to continue damage assessments and get a cost estimate for potential federal assistance.
Officials said they were still assessing buildings in the area.
A Red Cross evacuation center was set up at a high school, and crews were assessing damage to homes and roadways.
Authorities said Sunday evening that all bridges responded well to the earthquake.
John Callahan of the Napa City Fire Department said at one point Sunday there were a half-dozen multiple structure fires. One was at a mobile home park where four mobile homes have been destroyed by fire, and two others suffered major damage.
Public Works Director Jack LaRochelle assured residents the water has not been contaminated.
“The water is safe to drink,” he said. LaRochelle said that more than 60 water mains have been damaged; 20 have been turned off. He said none of the larger transmission lines had been damaged.
Napa Fire Chief Mike Randolph said firefighters were continuing to assess the damage to buildings in the downtown area, and the department was busy answering more than 100 calls reporting the smell of natural gas. That's "our primary attention right now," he said.
A number of buildings are damaged during the quake, but no number on how many was reported.
The city’s 911 emergency call system was maxed out, according to Napa Police Department operations captain Steve Potter, but he said there have been no reports of major disturbances. “We have relative calm for this magnitude of an earthquake,” he said.
Jennifer Jones Lee, who lives in the earthquake area, told Fox News the tremor “felt like someone just picked up the house, shook it for a while, then dropped it. It was incredibly violent.”
Arik Housley, who owns two grocery stores in the area, said he was awakened at about 3:30 a.m. by the shaking. “It was very jolting and probably went for 20 seconds . . . it was shaking pretty good,” said Housley, whose brother is Fox News senior correspondent Adam Housley.
Arik Housley said he passed a mobile home park where multiple fires could be seen as he drove to one of his stores to assess the damage. Housley said the shelving in his store had moved 2 feet to 3 feet from the wall, and much of his inventory had fallen to the floor, including $200 bottles of wine. Many merchants in the area forgo earthquake insurance because it’s too expensive, he said. A quake about 14 years ago resulted in about $30,000 in damage, he told Fox News, and speculated the current damage would be in excess of $100,000.
"There's collapses, fires," said Napa Fire Capt. Doug Bridewell, standing in front of large pieces of masonry that broke loose from a turn-of-the-century office building where a fire had just been extinguished. "That's the worst shaking I've ever been in."
Bridewell said he had to climb over fallen furniture in his own home to check on his family before reporting to duty.
The tremor set off car alarms and had residents of neighboring Sonoma County running out of their houses in the middle of night.
The USGS says the depth of the earthquake was just less than 7 miles, and numerous small aftershocks have occurred in the Napa wine country.
Aftershocks were expected to continue for several weeks, though State Geologist John Parrish said they would decrease in magnitude and it was unlikely that there would be a large follow-up earthquake. Still, he warned people to be careful because buildings that were damaged by the quake were now more susceptible to collapse from aftershocks.
“There’s fires, debris all over the streets, everywhere,” Napa resident Karen Hunt earlier told “Fox & Friends.”
Hunt said her husband, who is an engineer, shut off the gas line to their home to guard against explosions, then went to neighbors’ homes to do the same.
“Right now we’re just waiting for the aftershocks,” she said. She said she had not felt any, but reportedly there have been two, one at magnitude 2.5.
Hunt has said she has felt other earthquakes, but “this is way on top of anything I’ve ever felt.”
Hunt, who has lived in Napa since 1996, owns a winery. She said she heard from her partner that her 2011 and 2012 vintages had been destroyed.
“That’s pretty devastating if that’s the case,” she said.
Sunday's quake was felt widely throughout the region. People reported feeling it more than 200 miles south of Napa and as far east as the Nevada border. Amtrak suspended its train service through the Bay Area so tracks could be inspected.
California Highway Patrol Officer Kevin Bartlett said cracks and damage to pavement closed the westbound Interstate 80 connector to westbound State Route 37 in Vallejo and westbound State Route 37 at the Sonoma off ramp. He said there hadn't been reports of injuries or people stranded in their cars, but there were numerous cases of flat tires from motorists driving over damaged roads.
Thousands of small earthquakes occur in California each year, providing scientists with clear indications of places where faults cut the Earth's crust. There were 4,895 earthquakes in California between 1974 and 2003 with a magnitude of 3.5 or greater (about 163 per year).
LLC 501C- 4 UCC 1-308.ALL RIGHTS RESERVED WITHOUT PREJUDICE
Content and Programming Copyright 2014 By Patcnews The Patriot Conservative News Tea Party Network © LLC UCC 1-308.ALL RIGHTS RESERVED WITHOUT PREJUDICE All copyrights reserved By Patcnews The Patriot Conservative News Tea Party Network Copyright 2014 CQ-Roll Call, Inc. All materials herein are protected by United States copyright law and may not be reproduced, distributed, transmitted, displayed, published or broadcast without the prior written permission of CQ-Roll Call. You may not alter or remove any trademark, copyright or other notice from copies of the content. © All Copyrights reserved By Patcnews The Patriot Conservative News Tea Party Network
No comments:
Post a Comment