CathInfo.com

While both quakes were relatively small and did not lead to any reported injuries, geophysicist Stefan Burns warned that Sunday's seismic event occurred at a rare junction linking the Garlock to the infamous San Andreas Fault.
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The Garlock is a major east-west fault in Southern California, while the San Andreas is an 800-mile-long fracture running from Southern California north through the Bay Area and into the Pacific Ocean.

Burns warned that the earthquake struck exactly where these two faults meet, in an area that has not seen a quake this strong in more than 26 years.

According to the scientist, this small event at the junction could be an early sign that underground stress is building and the Garlock may play a role in the next major California earthquake - which many call 'The Big One.'
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While the Garlock moves to the left, the San Andreas moves to the right, with both fractures meeting near California's Frazier Park, creating a complicated 'push and pull' zone at a noticeable bend in the San Andreas.

However, rocks often get stuck, or locked up, as Burns said, instead of sliding smoothly past each other.

Over decades or centuries, enormous stress and energy build up in the locked sections, especially near this bend in the San Andreas.

When the stuck parts finally slip suddenly, it releases all the stored seismic energy as an earthquake, which, in the Garlock Fault's case, could trigger a major rupture producing an event close to magnitude 8.

'The Garlock fault is heavily locked up. It hasn't had a major rupture. Think magnitude 7.5 for 500 to a thousand years,' Burns said in a July 12 episode on his YouTube channel.

The geophysicist added that both the San Andreas and Garlock are both considered 'overdue for big ones, magnitude 7.5 or greater.'

Then, like looking at a huge map of the world, I could see what was happening on the land and with people. San Francisco was feeling it, but she was not in any way like Hollywood or Los Angeles. I seemed to see it was the GARLOCK FAULT, not just the SAN ANDREAS that was rocking San Francisco. It was moving just like that earthquake movie with Jeanette McDonald and Gable. I could see all those mountains coming together-the Sierra Nevada, and the San Andreas and Garlock.

I knew what was going to happen to San Francisco-it was going to turn over, because of Garlock. It would turn upside down. It went quickly, because of the twisting, I guess. It seemed much faster than Hollywood, but then I wasn’t exactly there. I was a long, long way off.

Then, I knew something was going to happen. I wondered what year it was. It certainly was not 1937. I saw a newspaper on the corner with a picture of the president. It surely wasn’t Mr. Roosevelt. He was bigger, heavier, big ears.

Plate tectonics cannot physically exist on a flat Earth. Tectonic mechanisms—such as crust creation at spreading centers and destruction at subduction zones—require a spherical surface and gravitational dynamics to balance material.