Rupture Process Inversion And Its Application To The Earthquake Emergency Of Large Earthquakes

Rupture process inversion is an important party in seismology. Reliable rupture process results help us better understand the rupture behaviors and disaster mechanism of earthquakes. Nowadays, there are at least two aspects for the development of rupture process inversion. The first is the joint inversion of seismic data and geodetic data, which constrains the results by using several kind s of data and results in a more stable result. The second, which aims at obtaining the major source characteristics to give effective information to disaster relief, is the fast rupture process inversion with seismic data. This paper mainly concentrates on three aspects. First, I introduce the rupture process inversion for the 2008 Wenchuan earthquake by use of seismic data only and joint use of seismic data and geodetic data, respectively. Second, I take the 2009 L'Aquila, Italy, earthquake as an example to discuss and compare the apparent source time function inversion method and direct wave inversion method. And finally, on the basis of the discussion and comparison,I perform the fast inversion on rupture process of large earthquakes and have obtained the results for 18 earthquakes since January 2009.In the study of Wenchuan earthquake, I inverted the teleseismic direct P waveform on vertical components based on a single finite fault model for the spatio-temporal rupture process on the fault. The displacement field on ground surface calculated with the inverted results consisted two areas with large displacement was in a good agreement with the distribution of two areas with intensity XI. Then I studied the spatio-temporal variation of source mechanism along the strike direction on a linear fault model, and found and confirmed the thrust fault near the epicenter and the right lateral strike slip to the northeast of the epicenter, which were consistent with the field observation of the Wenchuan earthquake. Finally, I constructed two listric faults and jointly inverted the teleseismic data, GPS data and InSAR data, with a grid search method adopted to get the best weight values of the three datasets in the inversion. The spatio-temporal images obtained from the joint inversion show that two slip-concentrated patches existed on the fault being near the epicenter and Beichuan city, respectively, which was also in a good agreement with the results of field observation.Two typical inversion methods inverting seismic data for rupture process, the apparent source time function inversion method and direct wave inversion method, were discussed and compared for their characteristics in their applications in the 2009 L'Auiqla, Italy, earthquake. On the basis of these discussions, I designed a work program for fast rupture process inversion by use of seismic data only. Since January 2009, I have obtained and released fast results of rupture process for 18 large earthquakes by optimizing the procedure. The quickly released results have taken an important party in the earthquake emergency and earthquake relief.