San Bernardino earthquakes could be due to "deep creep" in San Jacinto fault: study | TODAY & # 39; HUI | San Andreas

New research has suggested that there is an unusual reason behind small earthquakes around the San Bernardino Basin in California.

The study, published in Geophysical Research Letters, examined the deformation patterns of thousands of earthquakes under the San Andreas and San Jacinto faults, mainly centered at San Bernardino.

According to the survey, earthquakes have a vertical movement, while most earthquakes in the region have a horizontal slide.

"Over the past 36 years, seismic stations have recorded the deformation style of thousands of small earthquakes in the San Bernardino Basin, California," said the authors in a summary of the study.

"In this basin, many earthquakes less than 10 km deep show a deformation that does not correspond to what we expect for this region between the great devastating earthquakes along the San Jacinto and San Andreas faults". they added.

The researchers then used models to show that vertical movement could be produced in the basin of the northern part of the San Jacinto Fault, adding that he was moving backward rather than being stuck like the San Fault. Andreas the state of California.

They added that scientists usually use GPS to observe the creep of faults, but that did not work in this case because the San Andreas and San Jacinto faults are too close to each other.

"The results of this study demonstrate that small earthquakes occurring near and between faults may have a very different deformation style than large earthquakes caused by active faults. This means that scientists should not use the information recorded by these small earthquakes in the San Bernardino basin to predict the loading of the nearby San Andreas and San Jacinto faults, "the authors wrote.

This study was funded by the Southern California Earthquake Center, which is funded by cooperation agreements with the National Science Foundation and the US Geological Survey, which records earthquakes around the world, Science Daily reported.

A third of the small earthquakes in the region are deep creep, Cooke said.

"These small earthquakes are a very useful dataset, and if we pay more attention than in the past to the details they tell us, we can learn more about active fault behaviors that will help us better understand. the loading [the buildup of seismic pressure] that leads to major devastating earthquakes, "said Cooke in a statement, according to Gizmodo.

Geoscience professor Michele Cooke, who helped write the study, wrote: "Our catalog of earthquakes is increasing every year; we can see fewer and fewer each year, so we thought why not take advantage of the networks we built and we can look at them in more detail.

She said, "We do not want to wait for the flaws to move in a damaging earthquake, we want to take advantage of all the earthquakes that are occurring all the time to understand how the San Andreas and San Jacinto are charged. If we can understand how they are loaded, perhaps we can better understand when these defects will break. "

The study comes as a magnitude 3.4 earthquake hit San Bernardino on September 20, and a number of people on social media have noticed. No damage or injury has been reported. The earthquake struck around 5:44 am local time about 2 miles north of Colton, said the USGS.