PASADENA (CBSLA) — When the Ridgecrest earthquakes rocked Southern California this past summer, scientists said a fault capable of producing an 8.0-magnitude quake began sliding.
That finding was included in a study published Thursday by Caltech and NASA. According to the scientists, radar satellites picked up unprecedented movement on the 160-mile Garlock fault soon after a series of strong earthquakes hit the Ridgecrest area.
“It is significant, because we hadn’t seen this kind of activity occurring on the Garlock before,” Dr. Zachary Ross, an assistant professor of geophysics at Caltech, said. “The Ridgecrest earthquake, the magnitude 7.1, basically ended only a few miles away from this Garlock fault.”
Ross, who was the lead author of the study, said he believes the quakes and the movement on the fault were connected.
Just last month, the U.S. Geological Survey predicted that the Ridgecrest earthquakes were unlikely to trigger a larger temblor, but that the quakes increased the risk of a 7.5-magnitude quake or larger along the Garlock and other area faults.
Ross said scientists were not yet sure of how the new movement could impact future earthquakes, but he said that residents of Southern California should remember that major quakes were not confined to long-running fault lines like the San Andreas. Earthquakes could also occur from a collection of smaller faults, like the Ridgecrest series — which was caused by a cluster of 20 smaller faults.
“You can think of this as one fault triggering another like dominoes,” Ross said. “That really shows us that even if there is not a really large fault somewhere, you can still have significant seismic hazard, which is increasingly consistent with what we’ve been observing over the last several decades.”
Ross said that the Garlock fault has not produced an earthquake in 500 years, but said scientists would be watching it closely.