Damage to Earth’s crust from the magnitude 6.4 and 7.1 earthquakes that struck Southern California last week is visible in a kaleidoscopic satellite image released by NASA.
The Advanced Rapid Imaging and Analysis team at NASA’s Jet Propulsion Laboratory in Pasadena used satellite data to produce a map showing ruptures and displacements not visible to the naked eye — employing technology that has been developed over the last quarter of a century. The imagery was acquired Monday and compared with data from April 8.
The earthquakes were the largest to hit California in nearly 20 years and were felt as far away as Phoenix and Mexicali, Mexico. The temblors and the thousands of aftershocks that followed did not lead to major structural damage near the Ridgecrest epicenter but did have residents of nearby Trona worrying about their town’s future.
Authorities were investigating whether the death of a man 95 miles away in Pahrump, Nev., was tied to the earthquake. The man was pinned under a Jeep after the vehicle fell off its jacks.
On the NASA map, each color of the psychedelic-looking image represents 4.8 inches of ground displacement. Linear color lines indicate where an area is cracked open or disturbed.
“One of the things that we want to know after an earthquake happens is which fault moved and how far it moved,” said JPL’s Eric Fielding. “So, by using these satellite images, we can determine where the fault is, what lengths of the fault slipped in the earthquake and which fault moved the most. That allows us to better understand where future earthquakes could happen.”
It once took a year to obtain such satellite images, as was the case when capturing the effects of the magnitude 7.3 Landers earthquake in the Mojave Desert in 1992. But Fielding said that since 2016, images can arrive within three to four days.
The Japan Aerospace Exploration Agency provided the data to produce the map. NASA is building its own radar satellite at JPL. When it launches in roughly three years, Fielding said, the technology will be able to “map the whole Earth every 12 days.”