| Two of the most predominant characteristics of Surface Wave are Dispersion and Attenuation which are the effective tools to study the velocity structure and viscidity structure of the earth interior. By using the Attenuation property of the Rayleigh Surface Wave to invert the quality factor of crust and upper mantle, this paper yields the S-Wave quality factor 3D structure of Crust and Upper Mantle of China, and the viscidity structure of this area as well. This is of very important significance to understand the material property and geodynamic of corresponding area,, The surface wave attenuation mechanism and the inversion algorithm of attenuation and S-wave quality factor are discussed systemically in this paper. Some important fruits and understanding are resulted from the the Crust and Upper mantle Tomography of China.(1) Calculating of the Rayleigh Surface wave attenuation factor y. In the first step. 2861 surface wave recordings with seismic magnitude over 5.0 are selected under the criteria of Good-Wave and "Intact Recording", calculating the big-circle paths, and then about 284 two-station pairs of which two stations are along the same big-circle are chosen, among them there are about 260 pairs with difference of forward azimuth angle less than 5?. after further optimizing, 223 pairs which perfectly cover the China area are used in the final calculation. After doing the modifying of machine in calculating the real amplitude and frequency-time analysis to all selected records, the group velocity was calculated for each seismograms. Further using the phase-match for each seismograms , the fundamental-mode surface wave was separated. Using the two-station methods, the fundamental-mode interstation attenuation coefficients y was calculated . in order to avoiding the negative attenuation coefficients y. the frequence-domain Winner filter was used.(2) Calculating the Gridded Rayleigh wave attenuation factor y and Group Velocity. The LSQR algorithm is used to inverse the attenuation factor and group velocity under 4? X4?gridding and 2? X2?gridding, and4? X4?gridding attenuation and 2? X2?gridding group velocity are calculated respectively, based on the attenuation and velocity, the distribuation of Rayleigh wave quality factor QR are yielded finally.(3)Building the S-Wave quality factor Og3D structure of the Continental Crust andUpper Mantle of China area. The initial model (VS,VP,QB,p)based on previous work of this research group is adopted, and by terms of the relationship between the attenuation factor and S-Wave quality factor, the stochastic least square is conducted to inverse the O>> of ail layers under every grid, i.e. the QB structure of every uiut-column . and finally the transverse and vertical structure of research area can be easily generated.(4) The correlation property between the distribution of attenuation factor and that of the group velocity is indicated, in this study. Generally speaking, the high group velocity and low attenuation factor and high QR in the same area , but relatively low group velocity and high attenuation factor and low QR in the same area in China is the general distribution. The transverse and vertical variation of QB are very clear in the 3D calculation in the whole area, and the asthenosphere and some big structure arae is also showed very clearly. This study provides plentiful information for the interpretation of the material property and geodynamic of earth interior of China area, and also help to understand the interior viscidity structure of China area...
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