重力数据的平面全张量梯度角度边界识别方法

在倾斜角和θ图等传统边界识别方法基础上,通过对二者相互关系的分析,明确这两种方法均属于角度边界识别,并论述其他相关角度边界识别方法的理论依据及方法的特点。针对这些方法在识别深部地质体边界时产生偏移的问题,引入全张量梯度处理手段。将水平面视为整个与垂直方向相对的分量,利用水平梯度分量Vx和Vy的三方向导数V_xx,V_xy,V_xz和 V_yy, V_yx,V_yz的矢量特征,进行类似于倾斜角和θ图方法的比值计算,提出平面全张量梯度的角度边界识别和增强方法。模型试验表明,该方法具有更加准确的探测效果,可显示更多细节特征。塔里木盆地实测重力数据处理结果与地质资料对比表明,本文方法在构造单元分析中有良好的应用效果。

Gravity data edge identification using plane full tensor gradient angle

Based on analysis of their mutual relationships,we point out in the paper that both tilt angle andθmap are conventional angle edge identification methods.Meanwhile,we discuss the principle and feature of other angle edge identifications,and explain the similarity of all the angle edge identification methods.On this basis,we introduce the full tensor gradient processing to solve deeper geologic sources edge offset caused by angle edge identifications.Regarding horizontal plane as a whole relative to the vertical component and using the three directional derivative V_xx,V_xy,V_xz and V_yy, V_yx,V_yz of the horizontal gradient components V_x and V_y,we perform a similar ratio calculation of tilt angle andθmap,and propose a plane full tensor gradient angle edge detection and enhanced approach.Model tests shows that the new method gets more accurate identifications and more detailed features than that by conventional methods.Finally,we have applied the new methods on gravity data of Tarim Basin.The edge detection results demonstrate that the new method is effective in practical applications.