井中重力矢量数据联合反演研究

The study on joint inversion of borehole vector gravity data

井中重力矢量测量可以近距离感知地下目标体,获得地质体不同方向的重力异常特征,提高地下介质的纵向分辨率。这里首先基于点元法实现了井中重力矢量正演,通过模型正演计算,分析了井中三分量重力异常响应特征,然后基于相关性搜索的黄金分割算法实现了井中重力矢量联合反演,通过模型反演分析了井中重力不同分量数据联合反演的效果,验证了反演方法的可靠性。结果表明,井中三分量重力异常从不同方面反映了异常体分布特征,不同分量的峰值变化对异常体位置分布有较好的指示作用。反演中井中重力三分量同时联合反演效果最好,针对复杂模型,单井观测信息有限,多井多分量联合反演可以获得准确的反演结果。

The borehole vector gravity survey can perceive the target body at close range and obtain gravity anomaly of geological body in different direction,so it can improve the vertical resolution of the geological body.Firstly,we finished the forward calculation of borehole vector gravity and analyzed the response characteristics of borehole three-component gravity anomaly.Next,we realized the borehole vector gravity joint inversion based on the golden-section algorithm with correlation search and contrasted the joint inversion results of different component borehole gravity anomaly by the model calculation,which verifies the reliability of the inversion method.The results show that the borehole three-component gravity anomaly reflects the distribution characteristics of the geological body from different aspects,the peak value change of three-component gravity anomaly indicates the position of the geological body.Furthermore,the borehole three component gravity anomaly joint inversion can obtain the most reliable inversion results.In addition,the single borehole survey provides limited information to invert complex geological model,therefore,the multi-borehole and multi-component joint inversion can obtain accurate inversion results.