磁力张量数据的目标体边界识别方法探讨

Discussion of magnetic tensor data target body boundary identification methods

这里系统地介绍了磁张量数据边界识别数值计算的几种方法,包括利用磁张量不变量、水平梯度模法(the total horizontal derivatives,THDR)、解析信号法(The analytic signal amplitude,ASM)、Tilt梯度法、Tilt梯度的水平导数法、Theta图法、BZZ的水平梯度模法等,给出了各种方法的张量组合方式、各自的适用范围及优缺点,利用结果图中的极值点、零点或其他特征点来识别边界。通过对矩形棱柱体的模型验算,证明深度、磁倾角对边界识别影响较大,磁偏角几乎无影响。利用磁梯度不变量、解析信号法、Tilt梯度法得到目标体边界精确、完整,与实际目标体边界吻合度高,表明利用这些方法能够很好地完成磁张量数据的边界识别。

Several methods of the magnetic tensor data boundary identification of numerical calculation are systematically introduced in this paper,including using the magnetic tensor invariant,horizontal gradient modulus method（the total horizontal derivatives,THDR）,analytic signal method,the analytic signal amplitude（ASM）,Tilt gradient method,the horizontal derivative of Tilt gradient method,Theta map method and the level of the BZZgradient modulus method.Tensor combination of various methods,their respective applicable scope and the advantages and disadvantages are given.Using the results the extreme value point,zero point,or other feature points in the graph to identify boundary.Through the calculation of rectangular prism model,proving that the depth,dip angle has greater influence on the boundary identification,magnetic declination almost had no effect.The geological edges by using the method of magnetic gradient in-variants,analytic signal and Tilt gradient method are accurate and complete.The result is in accordance with model edge.Showing that is able to complete the boundary identification of the magnetic tensor data.