Crustal thicknesses and Poisson's ratios in China by joint analysis of teleseismic receiver functions and Rayleigh wave dispersion

Abstract

A new grid search scheme, which extends the stacking H-κ algorithm to multi-layered crustal models and fits observed dispersion of surface wave group velocity simultaneously, is proposed to estimate the thickness, Poisson's ratio, and average P wave speed of the crust. We first apply it to a synthetic data of a 2-layered crustal model. Then we show the results analyzing records from 45 permanent broadband seismic stations in China. The estimates at six stations agree well with results from deep seismic sounding profiles. The crustal thicknesses agree in general with the Crust 2.0 model. We find that the Poisson's ratio in the Yangtze platform is rather low compared with the other two platforms. The stations along the southeast coast of China have higher Poisson's ratios. The Poisson's ratio of the whole region tends to increase as the average P-wave velocity. Copyright 2007 by the American Geophysical Union.