California Earthquake Left a 100 ft Wide 2 mile long Crack in the desert floor
New satellite imagery shows that one of the strongest earthquakes to hit Southern California in decades left a serious mark there.
The imagery shows what looks like one massive crack, known as a surface rupture, emanating from near the epicenter of Friday’s 7.1-magnitude temblor in the Mojave Desert just outside of Ridgecrest, California.
Approximately 30 miles of a fault ruptured to the surface and produced physical signs of its violent movement, Dr. Morgan Page, a geophysicist at the USGS in Pasadena, California, told weather.com. This deformation of the earth is all a byproduct of the fault’s unique movement.
“The fault that ruptured in the 7.1-magnitude earthquake is what we call a right-lateral strike-slip fault,” Dr. Page said. “What that means is that if you’re standing on the ground on one side of the fault looking across it, you will see the ground on the other side of the fault move to the right. That’s true no matter what side you stand on.”
That movement produced horizontal offsetting of the ground from 6 to 10 feet in many places.
Surface rupture is typical during a quake of this magnitude, Dr. Page said, but added that the resulting offsets were “quite substantial” and that USGS surveyors were seeing them “over a pretty wide area.”
Water also seems to be displaced in the satellite image, which Dr. Page said can happen after earthquakes, but there were no specific reports to confirm or deny and such an observation was impossible to make from one satellite image, she said.
The 7.1 quake followed a 6.4 earthquake on Thursday. All told, the two earthquakes ruptured gas lines, set fire to several homes in Ridgecrest and damaged roads and dozens of homes in Trona, the Associated Press reported. Luckily, no one was seriously injured or killed in the earthquakes.
The USGS is currently surveying and mapping the areas impacted by the quake, including surface ruptures like this one, which Page said hopefully will lead to a new understanding of the seismic environment there.
“We haven’t had an earthquake this size in Southern California in 20 years,” said Dr. Page. “We’re going to learn a lot more not just about the faults in the area, but the earth structure in the area and the ground motion generated by the earthquake.”