移去-恢复法校准重力异常场及其应用

对经典移去-恢复法进行改进，利用EGM2008地球重力场模型、地表重力/GPS联合观测数据和ASTER数字地形模型，提出考虑地形梯度特征的区域重力场校准算法，同时针对我国动态重力区域网布设情况，对重力场的校准区域范围进行更为合理的设定。通过与经典移去-恢复法在川西地区实际应用的比较发现，改进模型能够将川西地区重力场模型数据的标准差从65.09 mGal降至61.24 mGal，在结合地形梯度影响后，能够将标准差进一步降至59.31 mGal。采用国际重力局最新发布的283个重力数据对喜马拉雅东构造结及邻区的重力场进行校准，结果表明，布格重力异常和地形数据有很强的正相关，该区中东部存在明显的均衡重力异常低值区。

Study on the Remove-Restore Theory of Refining Gravity Anomaly and Its Application

The classical remove-restore theory is improved. We propose a regional gravity field calibration algorithm considering the gradient feature of terrain using EGM2008 (the satellite gravity field model), surface gravity/GPS joint observation data and ASTER digital terrain model. Based on the layout of the dynamic gravity regional network in China, the calibration range of the gravity field is more reasonable. Compared with the classical application of removal-restoration method in western Sichuan, the new calculation shows that the standard removal-restoration method model can reduce the standard deviation of the gravity field model data in western Sichuan from 65.09 mGal to 61.24 mGal, and combined with the impact of the terrain gradient, it can be further reduced to 59.31 mGal. In this paper, 283 gravimetric data recently published by the International Gravity Bureau are used to calibrate the gravitational field in the eastern Himalayan syntaxis and adjacent areas. Through the Bouguer gravity anomaly map, it is obvious that there is a strong positive correlation between the Bouguer gravity anomaly and the terrain distribution; furthermore, there is a clear area of low value isostatic anomalies in the central and eastern parts of the study area.