Study of China lithosphere by receiver function and surface wave tomography

• Antragsteller: Dr. Xiaohui Yuan
• Fachliche Zuordnung: Physik des Erdkörpers
• Förderung: Förderung von 2006 bis 2011
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 26476817

High-resolution seismic observation of the lithosphere is hampered due to a number of factors. (1) As a gradient transition zone and as an upper boundary of a low-velocity zone (asthenosphere), the lithosphere-asthenosphere boundary (LAB) is hard to be detected by body waves or wide-angle seismic reflections; (2) Surface wave studies sometimes suffer from low resolution due to sparse station distribution. It is, however, shown that the resolution of surface wave tomography can be greatly improved by including higher mode surface waves (Priestley et al., 2005). The recently developed S receiver function method appears to provide another means to observe the LAB (Li et al., 2004; Kumar et al., 2005a,b,c). In the last several years China significantly expanded the permanent seismic network to more than 80 broadband stations. We propose here to combine applications of P and S receiver function methods with multi-mode surface wave tomography to study the lithospheric structure of China. Surface wave models might be used to improve the receiver function estimates in two ways: firstly they can straightforwardly be used in a joint inversion, where they remove some of the ambiguities associated with inversions of receiver functions alone; secondly they can provide appopriate models for time-depth conversion of the receiver functions. Knowledge about the the entire lithosphere, not only the crust, will significantly improve our understanding of plate tectonics of China and the Indo-Asian collision and of large intraplate earthquakes.

• DFG-Verfahren: Sachbeihilfen