Estimation of the fault-near ground motion of the 2010 Yushu, Qinghai, Ms7. 1 earthquake

On April 14th, 2010, an M(s)7. 1 earthquake occurred in Yushu Tibetan Autonomous State, Qinghai province, China. It resulted in a great loss of life and property, and especially, the Yushu, a city southeastern to the epicenter, was most seriously damaged. We calculated the ground motion, including displacement and velocity, near the causative fault using the dynamic model of rupture process from the inversion of teleseismic waveform data and the crust model of Crust2. 0, reconstructing an image of the fault-near ground motion at the time of quaking. The image shows that there appeared the evident Doppler's effect, generated by the unilateral rupture process of the source. Seismic waves radiated out wards from the epicenter, but those propagating toward southeast along the fault had much larger amplitudes, and were much more crowded. The Yushu city happens to lie on not only where static displacement was larger also where the stronger velocity waves and displacement waves ran through. There should be no doubt that the Doppler's effect caused by the unilateral rupture process was the main reason why the most disastrous damage happened in the Yushu city, in spite the estimated ground motion was not accurate enough compared with the real one.