Temporal and spatial pattern of the 1997 Manyi earthquake using differential InSAR

Since the beginning of indentation of the Indian Plate toward the Eurasia Plate at round 50 Ma, the convergence of these two continental plates had been changing the surface of our earth. The Indian plate is colliding with Eurasian plate at about 58mm/yr (Bilham et. al 1998); the high strain rate caused by this rapid convergence provides the source to the construction of the Himalaya and the Tibetan plateau. The 1997 Manyi earthquake (Mw=7.5) is one of the largest earthquake occurred in the Tibetan plateau, followed by another even greater seismic events 2001 Kokoxli earthquake (Mw=7.9) in north western part of Qinhai Province. Although the epicenters of these two events are 500 km apart, both events occurred along the Kunlun fault that is trending east-westward and spatially spanned about 1,000 km. The region along the Kunlun fault in northern Tibet serves as a natural laboratory for studying earthquakes and earthquake sequences. By InSAR with ERS radar images, we establish the time series of, to the first order, the deformation rate in the vicinity of the epicenter of 1997 Manyi earthquake. We generate interferograms associated with coseismic deformation to improve our understanding the rupture style and its underlying mechanism. Preliminary investigation of the interferogram revealed that there may be at least two surface ruptures produced during the earthquake.