Study on Radar Differential Interferometry Technology and It’s Application to Mani Earthquake Using Ers-1/2 Sar Data: a Case Study in China

Mani Earthquake, occurred on Nov. 8, 1997 in Tibet, China, is the strongest event in China since 90’s in 20 century. Investigation and research of its principle and geometry, dynamics related to surface rupture zone is very significant to analyze the development and evolution of China’s earthquake in the future. In this study, we investigate the distribution of surface deformation and extract displacement information of the earthquake rupture zone using differential SAR (ERS1/2 SAR) interferometry. The data set related to our study area are ERS1/2 SLC SAR images (April 15, April 16, 1996 ERS-1 and Dec. 2, 1997 ERS-2) provided by European Space Agency. We analyzed factors related to the surface deformation detecting interferogram along the Margaichace-Ruolacuo fault under the special regional environmental conditions. From the changing interferogram, we concluded that the zone around Margaichace-Ruolacuo fault is the most severely deformed and the most possibly rupturing area; epicenter is located in this zone. Also we concluded from analyzing the fringe patterns that left-lateral shear movement is the whole deforming mechanism, furthermore, the offsets are also quantitatively estimated. We inferred that the horizontal offset displacement for the southern side at least reaches 2.8m and 1.75m at least for the northern side of the fault. All these results agree well with the slip measured in the field, with the displacement measured by surveying, and with the results of an elastic dislocation model. * Corresponding author.