基于三维重力反演技术的航空重力梯度标定方法

Methodology to calculate full tensor of airborne gravity gradient based on 3D gravity inversion

将三维重力反演技术引入航空重力梯度标定研究,给出利用地形数据和地面重力数据解算航空重力梯度全分量的一种新技术路径.通过理论模型试验,验证了技术的有效性和可靠性,模型试验结果表明:重力反演解的非唯一性对航空重力梯度解算精度影响较小,解算误差低于反演残差水平,证明此技术可用于处理非格网含噪的实测重力数据.将此技术应用于五大连池尾山地区,联合地面加密实测重力异常数据、SRTM数字地形模型和EGM2008全球重力场模型解算此区域航空重力梯度扰动全分量,解算误差低于5.8 E,满足航空重力梯度标定要求.

The 3D gravity inversion method was introduced into airborne gravity gradients calculation and a new technique that using topographic data and ground gravity data was presentd to calculate full tensor of airborne gravity gradient.The effectivity and reliability of this technique was evaluated by theoretical model.Model test shows that,non-uniqueness of gravity inversion solution has low influence to the precision of calculated airborne gravity gradients,and the calculation error is lower than inversion error level.It indicates that 3D inversion technique is capable for processing discrete and noisy in-situ gravity data.This technique was applied in Weishan Volcano area in Wudalianchi to calculate gravity gradients at flight altitude,by using ground dense in-situ gravity anomaly data,with SRTM digital topographic model and EGM2008 global gravity field model to calculate regional airborne gravity gradients.The calculation error is lower than 5.8 E,which satisfies requirement of calibration of airborne gradiometer.