Crustal shear-wave velocity structure beneath Anhui Province revealed by receiver function inversions

According to the teleseism recorded by twenty-five stations of Anhui Network, this paper has used the method of frequency domain deconvolution to extract receiver functions, and the H-Kappa scanning method to invert the crust thickness and v_P/v_S ratio under the stations in Anhui area. The results show that the crust thickness of Anhui area can be divided into three regions, including the Dabie Mountains in the southwest of Anhui, the mountains in southern Anhui, and the plains in northern Anhui. The crustal thickness is in the range of 35—39 km beneath the stations in the Dabie Mountain area, in the range of 33—36 km in southern Anhui, and in the range of 30—33 km for plains in northern Anhui. The results of this study have a good correlation with the geological tectonic setting of Anhui. Meanwhile, the H-K results show that the ratio of velocity beneath the stations in Anhui is basically from 1.7 to 1.8 with little change. Under the premise that the inclined angle of the interface is not large, the S-wave velocity structure is obtained by waveform fitting of the receiver functions which are implemented using the waveform inversion of horizontal uniform stratified model. And the calculation results show that the S-wave velocity on the surface of Moho is within the range of 3.6—3.9 km/s, while that is about 4.3—4.6 km/s at the bottom of Moho. The velocity fluctuation of Moho beneath stations in Anhui is not extremely obvious.