Tuesday, February 23, 2016

PLANETARY TREMORS: Strong 4.9 Magnitude Earthquake Rattles California - The Biggest In More Than A Year; Study States That California's "BIG ONE" Could Trigger Super Cycle Of DESTRUCTIVE QUAKES! [MAPS]

USGS earthquake location.

February 23, 2016 - CALIFORNIA, UNITED STATES - A 4.9-magnitude earthquake shook just after 4 p.m. Tuesday about 22 miles outside of Bakersfield, according to the U.S. Geological Survey.

The quake is the biggest earthquake in California in more than a year, according to the USGS. Lucy Jones, a USGS seismologist, told KPCC that Tuesday's earthquake is the biggest shake the state has had since 2014's 5.1 in La Habra and the 6.0 Napa earthquake.

There was also a 5.7 earthquake offshore in January 2015, and a 4.8 that came close just a week ago (it was a 4.77, while this was a 4.9).

"All of California is earthquake country, this is a relatively less common site down under the basin — but we have seen earthquakes here before," Jones said.


USGS shakemap intensity.

The earthquake was reportedly 13 miles deep, which is why it was felt as far away as the Los Angeles area, Jones said. According to KPCC's earthquake tracker, 280 people have reported they felt the quake.

There were no injuries or damages reported, Kern County Fire Department spokesperson James Dowell told KPCC.

A map from the USGS shows locations of where people felt the shake, and how big of an impact the shake had.

To tell USGS what you felt, fill out the "Did you feel it" report on the agency's website. - SCPR.


California's "BIG ONE" Could Trigger Super Cycle Of DESTRUCTIVE QUAKES - Study! 

A major earthquake – the Big One – is statistically almost certain in California in the coming decades, and there is even worse news below the ground: it is likely to be followed by a series of similar-sized temblors, according to a leading seismologist.

The current relatively quiet seismic period – in which “far less” energy is being released in earthquakes than it is being stored from tectonic plate motions “cannot last forever,” said University of Southern California earth sciences professor James Dolan while delivering a new paper during the Seismological Society of America conference in Pasadena.


Image from usgs.gov

“At some point, we will need to start releasing all of this pent-up energy stored in the rocks in a series of large earthquakes,” Dolan stressed.

The earthquake could spark a “super cycle,” meaning “a flurry of other Big Ones, as stresses related to the original San Andreas fault earthquake are redistributed on other faults throughout Southern California,” he said.


Earthquake fault heightens California tsunami threat, experts say http://fw.to/ahAEFkh
 

While there would not be a literal cannonade of destruction, the earthquakes could come just decades apart, like, for example, the 7.5 major quake in 1812 on the San Andreas fault, followed by a 7.7 in 1857.

Incidentally, that was the last major earthquake in that system, one of the factors that led the US Geological Survey to conclude last month that there is a 7 percent chance of an earthquake measuring 8.0 or greater on the Richter scale to occur in California in the next 30 years alone.

Scientists behind the March report said that the fault lines in California – which is home to almost 40 million people – are much more interconnected than previously thought, and similarly claimed that “tectonic forces are continually tightening the springs of the San Andreas fault system, making big quakes inevitable.”


The 1906 San Francisco earthquake struck the coast of Northern California at 5:12 a.m. on Wednesday, April 18.


Dolan made his discovery while studying the Garlock fault line ‒ state’s second-biggest. He said the Garlock was “switched off” for 3,500 years before creating four major earthquakes from 250 AD to 1550. During that period, the fault lines were moving four times as fast, as during the pause.

“We’re not focused especially on the seismic threat posed by the Garlock,” said Dolan.

“This study focuses on the deeper scientific significance, the more general importance of how faults interact with one another over long time and distance scales, and fundamentally on helping us to understand how faults store and release energy,” he added. “These are issues of absolutely basic importance for our understanding of seismic threats from all faults.”

The most destructive recent earthquake in California was the Northridge in 1994, which caused more than 50 deaths and $20 billion worth of damage despite its modest magnitude of 6.7. - RT.







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