Researchers with NASA’s Jet Propulsion Laboratory have used satellite data to map out surface displacement from the recent California earthquakes. On July 4., 2019, a magnitude 6.4 earthquake hit the southern California region. The next day, July 5, a magnitude 7.1 struck near the city of Ridgecrest, about 150 miles northeast of Los Angeles. More than 1,000 aftershocks were registered after the July 5 earthquake. Surface displacement as a result of these earthquakes was measured using synthetic aperture radar (SAR) data from the ALOS-2 satellite. This data can measure areas of the earth where the ground either fell or rose as a result of the quakes’ tremors.
Using data from imagery taken before the earthquakes on April 16, 2018 and after July 8, 2019, researchers from NASA’s Advanced Rapid Imaging and Analysis (ARIA) team were able to measure ground displacement to produce this Interferometric Synthetic Aperture Radar (InSAR) map. Each color cycle represents 4.8 inches (12 centimeters) of ground displacement.