Wednesday, June 23, 2010
The magnitude-7.2 earthquake that struck near Calexico on Easter Sunday shifted the Earth's crust in the area about 31 inches downward and to the south, according to radar images and data collected by researchers at NASA's Jet Propulsion Laboratory.
Airborne radar images of the area taken by the JPL-developed Uninhabited Aerial Vehicle Synthetic Aperture Radar were posted online by NASA for the first time today.
Researchers used data collected by the airborne radar to detect changes in the distance between the aircraft and the ground over repeated GPS-guided flights. According to JPL, they combined data from flights on Oct. 21 and April 13 to determine the deformities in the Earth's crust.
The UAVSAR has been mapping the San Andreas and other faults from north of San Francisco to the Mexican border every six months since spring 2009, looking for ground motion and increased strain along faults, according to NASA.
"The goal of the ongoing study is to understand the relative hazard of the San Andreas and other faults to its west like the Elsinore and San Jacinto faults, and capture ground displacements from larger quakes,'' said JPL geophysicist Andrea Donnellan.
The radar images can be seen online at www.nasa.gov/topics/earth/features/UAVSARimage20100623.html.