摘要
Qinghai-Tibet Plateau is the most complex region for crustal thickness inversion, while high-resolu- tion earth gravity model （EGM） makes it possible to obtain high precision gravity anomaly, which is a key pa- rameter to depict the Earth＇ s inner structure in geodesy domain. On the basis of this principle, we calculated the Bouguer gravity anomalies in Qinghai-Tibet Plateau with EGM2008 and SRTM6.0 by efficient high-degree spherical harmonic synthesis algorithm. In order to obtain the gravity anomaly caused by Moho density mutant, the noises caused by the topography was removed by wavelet details. Then, the crustal thickness was corrected on the basis of CRUST 2.0 with the deep-large-scale single density interface formula. The inversion result indi- cates that the crustal thickness in Qinghai-Tibet Plateau is between 50 km and 75 kin, which is in correspon- dence with the recent science research result. Compared with the 2 degree CRUST 2.0 model, the spatial resolution of crustal thickness in our research can reach 40 arc minutes. In addition, there is a positive relationship between the inversed crustal thickness and topography, which can prove the effectiveness of Airy-Heiskanen isostatic model in gravity reduction.
Qinghai-Tibet Plateau is the most complex region for crustal thickness inversion, while high-resolu- tion earth gravity model （EGM） makes it possible to obtain high precision gravity anomaly, which is a key pa- rameter to depict the Earth＇ s inner structure in geodesy domain. On the basis of this principle, we calculated the Bouguer gravity anomalies in Qinghai-Tibet Plateau with EGM2008 and SRTM6.0 by efficient high-degree spherical harmonic synthesis algorithm. In order to obtain the gravity anomaly caused by Moho density mutant, the noises caused by the topography was removed by wavelet details. Then, the crustal thickness was corrected on the basis of CRUST 2.0 with the deep-large-scale single density interface formula. The inversion result indi- cates that the crustal thickness in Qinghai-Tibet Plateau is between 50 km and 75 kin, which is in correspon- dence with the recent science research result. Compared with the 2 degree CRUST 2.0 model, the spatial resolution of crustal thickness in our research can reach 40 arc minutes. In addition, there is a positive relationship between the inversed crustal thickness and topography, which can prove the effectiveness of Airy-Heiskanen isostatic model in gravity reduction.
基金
supported by the National 973 Program of China(2013CB733302)
the National Natural Science Foundation of China(41131067,41174020,41374023)
the open fund of State Key Laboratory of Geographic Information Engineering(SKLGIE2013-M-1-3)
the open fund of Key Laboratory of Geospace Environment and Geodesy,Ministry of Education(13-02-05)
the Fundamental Research Funds for the Central Universities(2014214020203)
