The San Andreas fault system is more than 800 miles (1,300 kilometers) long, and as deep as 10 miles (16 km) in some areas.
Credit: Lloyd Cluff by means of Corbis Documentary/Getty Images Plus
Twin quakes– the greatest to strike Southern California in years– rattled a dry stretch of the Mojave Desert on Thursday (July 4) and Friday (July 5), sending out seismic waves rippling through Earth that might be felt from Los Angeles to San Jose.
Luckily, no deaths were reported, partially due to the fact that the 2 quakes struck a sparsely inhabited area of the Golden State. The burst faults were not part of the San Andreas Fault system, which snakes 800 miles (1,287 kilometers) from north to south along the shoreline, where the North American and Pacific plates fulfill.
However exists a possibility that these quakes could in some way move tension to the San Andreas Fault, possibly setting off the much feared “Big One” in among the state’s most populated cities? [Photo Journal: The Gorgeous San Andreas Fault]
It is in theory possible, though there’s no recognized link in between the 2 fault systems, geophysicists state. And due to the fact that there’s still a lot to learn more about the complex fault system that burst, it’s challenging to state whether the San Andreas Fault handled extra tension from the current quakes, they state.
The magnitude-7.1 quake on July 5 burst a recognized part of the Little Lake Fault zone, while the magnitude-6.4 quake that struck the previous day burst a formerly unmapped area of the fault zone, Glenn Biasi, a geophysicist with the USGS in Pasadena, California, informed Live Science in an e-mail. If you take a look at a map of faults, you ‘d see that the Little Lake Fault zone and the San Andreas Fault zone are not extremely close together.
” We do not understand of a certain relationship of these earthquakes to the San Andreas,” Biasi stated.
That stated, geologists are still finding out a lot about the Little Lake Fault zone.
A lot of the specific faults in this zone are active, “and due to the fact that they are buried, we most likely do not understand them all. This location does not fit the book image of sides of a plate moving past one another,” Biasi stated.
Since these faults are so complex and we understand reasonably little about them, it’s tough to state how they will communicate with the San Andreas. It is possible that the current quakes included tension to the San Andreas Fault, though “we do not have a great way to evaluate the probability,” stated Michele Cooke, a geoscientist at the University of Massachusetts – Amherst.
“ The San Andreas hasn’t insinuated a long while If the fault is packed to the point where it is practically all set to slip, then it is possible that the current earthquake might include simply adequate shear tension to the San Andreas to trigger it to slip. Additionally, the slip of these current earthquakes might unclamp the San Andreas fault, making it simpler to slip,” Cooke informed Live Science in an e-mail.
Another appealing possibility is that there’s a larger shakeup underground that these current earthquakes are unmasking.
A few of the motion on the San Andreas Fault is moving east, crossing the Mojave Desert and directing the eastearn side of the Sierra Nevada range of mountains, Biasi stated.
3 huge ruptures, consisting of one in 1992, 1999 and the current Ridgecrest quakes all appear to be lined up, and belong to what’s referred to as the Eastern California Shear Zone (ECSZ), Cooke stated. By contrast, the southern part of the San Andreas Fault hasn’t had a significant rupture in 150 years, she stated.
” Some recommend that we are seeing a migration of the active plate border far from the San Andreas Fault,” Cooke stated. “I’m not yet persuaded of this, however I do believe that this current (geologically speaking) cluster of earthquakes in the ECSZ is extremely fascinating.”
Initially released on Live Science