© Jianbao Sun; ALOS data: JAXAAn ALOS Phased Array type L-band Synthetic Aperture Radar (PALSAR) interferogram that shows the surface deformation associated with the 2008 Wenchuan earthquake.
Using satellite radar data and GPS measurements, Chinese researchers have explained the exceptional geological events leading to the 2008 Wenchuan Earthquake that killed nearly 90,000 people in China's Sichuan Province.
"One of the very fundamental issues for understanding an earthquake is to know how the rupture is distributed on the fault plane, which is directly related to the amount of ground shaking and the damage it could cause at the surface," said Dr Jianbao Sun of the Institute of Geology, China Earthquake Administration (IGCEA).
To learn this, Sun and Prof. Zhengkang Shen of IGCEA and Peking University's Department of Geophysics, and collaborators acquired two kinds of satellite radar data: Advanced Synthetic Aperture Radar (ASAR) data in C-band from ESA's Envisat satellite and Phased Array type L-band Synthetic Aperture Radar (PALSAR) data from Japan's ALOS satellite.
Applying a technique called SAR Interferometry (InSAR) on the data, the researchers produced a set of 'interferogram' images covering the entire coseismic rupture region and its vicinity. This interferometric map revealed the amount and scope of surface deformation produced by the earthquake.