Rings of the Ridgecrest Earthquakes. In Art of Science

Caption: Satellite-based radar imaging captures surface change caused by earthquake motion in eastern California
Participant category: Postdoctoral
Department: Scripps Institution of Oceanography

When earthquakes happen, they not only cause ground shaking, but they also cause changes in the shape of the surface of the Earth. We can measure these changes in a number of ways, but one way to see the changes in broad scope, in high spatial resolution, is to look from above, using satellite-based Synthetic Aperture Radar (SAR) data.

What we see here is two Sentinel-1 mission satellite radar images that were taken before and after the July 2019 Ridgecrest, CA earthquake sequence that have been interfered, or differenced, to highlight how the surface has changed between the two collection dates. Each rainbow of color, varying from black to pale yellow indicates 28 mm of surface change. The bullseye at the center of the image indicates the locations of the M6.4 and M7.1 earthquakes, and the higher number of “rainbows”, the more surface change that occurred. In white, we plot the locations of surface ruptures, where the localized earthquake energy caused permanent breaks and faults to open at ground level.

These kinds of images help us understand the extent of earthquake deformation in a regional context, and allow us to better quantify future earthquake hazards for the area.