基于Cryosat2与船载重力测量数据反演我国近海海域重力异常

Method of Construction Gravity Anomaly in Coastal Region of China Using Cryosat2 Altimetric and Shipborne Data

摘要:

基于Cryosat2三年半的卫星测高GDR(geophysical data records )数据，使用海面高梯度，依据最小二乘配置方法得到了南海部分海域垂线偏差格网，结合移去恢复技术采用逆VeningMeinesz的球面一维傅里叶变换算法快速计算我国近海海域测高重力异常CASM_GRA.与船载重力测量数据融合后，重力场精度在2.75~5.38 mgal之间，平均偏差在-0.21~0.45 mgal之间.与DTU13重力场模型相比，平均值最大改进为12.98 mgal，标准差最大降幅近3.40 mgal.与Sandwell V23.1模型相比，平均值最大改进为13.58 mgal，标准差最大降幅为1.09 mgal.

Abstract:

Based on three and a half years of satellite altimetric GDR data of cryosat2, the deflection of the vertical grid were obtained by using sea surface height gradient data and the least square collocation method in coastal region of China. The inverse Vening Meinesz formula and the removerestore technique were adopted to get sea gravity anomaly in the interested region. After fusion with the shipborne gravity data,the precision of the constructed gravity anomaly was found to be from 2.75 mgal to 5.38 mgal and the mean value was from -0.21 mgal to 0.45 mgal. Compared with DTU13 gravity field model, the maximum mean value improvement was 12.98 mgal and standard deviation improvement was 3.4 mgal. Compared with the Sandwell V23.1 gravity field model, the maximum mean value improvement was 13.58 mgal and standard deviation improvement was 1.09 mgal.