论文部分内容阅读
In this paper,we analyze lithospheric density distribution of China and surrounding regions on the basis of 300300gravity data and 1 1 P-wave velocity data.Firstly,we used the empirical equation between the density and the P-wave velocity difference as the base of the initial model of the Asian lithospheric density.Secondly,we calculated the gravity anomaly,caused by the Moho discontinuity and the sedimentary layer discontinuity,by the Parker formula.Thirdly,the gravity anomaly of the spherical harmonics with 2e40 order for the anomalous body below the lithosphere is calculated based on the model of EGM96.Finally,by using Algebra Reconstruction Techniques(ART),the inversion of 300300residual lithospheric Bouguer gravity anomaly caused by the lithosphere yields a rather detailed structural model.The results show that the lithospheric density distribution of China and surrounding regions has a certain connection with the tectonic structure.The density is relatively high in the Philippine Sea plate,Japan Sea,the Indian plate,the Kazakhstan shield and the Western Siberia plain,whereas the Tibetan Plateau has low-density characteristics.The minimum value of density lies in the north of Philippines,in the Taiwan province and in the Ryukyu island arc.
In this paper, we analyze the lithospheric density distribution of China and surrounding regions on the basis of 300300 gravity data and 1 1 P-wave velocity data. Firstly, we used the empirical equation between the density and the P-wave velocity difference as the base of the initial model of the Asian lithospheric density. Secondarily, we calculated the gravity anomaly, caused by the Moho discontinuity and the sedimentary layer discontinuity, by the Parker formula. Thirdly, the gravity anomaly of the spherical harmonics with 2e40 order for the anomalous body below the lithosphere is calculated based on the model of EGM96. Finally, by using Algebra Reconstruction Techniques (ART), the inversion of 300300residual lithospheric bouguer gravity anomaly caused by the lithosphere yield a rather detailed structural model. The results show that the lithospheric density distribution of China and surrounding regions has a certain connection with the tectonic structure. Density is relatively high in the Philippine Sea plate, Japan Sea, the Indian plate, the Kazakhstan shield and the Western Siberia plain, and the Tibetan Plateau has low-density characteristics. Minimum value of density lies in the north of Philippines, in the Taiwan province and in the Ryukyu island arc.