Numerical modeling of anisotropy paradoxes in direct current resistivity and time-domain induced polarization methods  

直流电阻率法和时间域激发极化法各向异性反常现象数值模拟

作　　者：Song Tao Liu Yun Wang Yun and Li Bin 宋滔;刘云;王赟;李斌(贵阳学院数学与信息科学学院,贵阳550002;中国科学院地球化学研究所,矿床地球化学国家重点实验室;云南大学地球科学学院,昆明650091;中国地质大学(北京)地球物理与信息技术学院,北京100083;四川省公路规划勘察设计研究院有限公司,成都610041)

机构地区：[1]College of Mathematics and Information Science,Guiyang University,Guiyang 550005,China [2]State Key Laboratory of Ore Deposit Geochemistry,Institute of Geochemistry Chinese Academy of Sciences,Gui Yang 550081,China [3]College of Earth Sciences,Yunnan University,Kunming,650500,China [4]School of Geophysics and Information Technology,China University of Geoscience,Beijing,100083,China [5]Sichuan Highway Planning,Survey,Design And Research Institute Ltd,Chengdu 610041,China.

出　　处：《Applied Geophysics》2021年第1期117-127,130,共12页应用地球物理（英文版）

基　　金：the special funding of Guiyang science and technology bureau and Guiyang University[GYUKY-[2021]];the National Key Research and Development Program of China-Geophysical Comprehensive Exploration and Information Extraction of Deep Mineral Resources(2016YFC0600505);the National K&D Program(2018YFC1504901,2018YFC1504904).

摘　　要：Based on an analytical solution for the current point source in an anisotropic half-space,we study the apparent resistivity and apparent chargeability of a transversely isotropic medium with vertical and horizontal axes symmetry,respectively.We then provide a simple derivation of the anisotropy paradoxes in direct current resistivity and time-domain induced polarization methods.Analogous to the mean resistivity,we propose a formulation for deriving the mean polarizability.We also present a three-dimensional finite element algorithm for modeling the direct current resistivity and time-domain induced polarization using an unstructured tetrahedral grid.Finally,we provide the apparent resistivity and apparent chargeability curves of a tilted,transversely isotropic medium with diff erent angles,respectively.The subsequent results illustrate the anisotropy paradoxes of direct current resistivity and time-domain induced polarization.本文基于点源场均匀半空间各向异性介质的解析解,研究了横向同性介质中电性对称轴分别为垂直和水平时地表测量的视电阻率和视极化率特点,证明了关于电阻率和极化率各向异性反常现象,并类比于平均电阻率提出了一种横向同性介质中平均极化率的计算方式。本文进一步基于有限单元法实现对时间域激发极化法三维正演计算,其中使用非结构四面体单元剖分灵活地实现了对任意极距的模拟。通过模拟对称轴倾角不同的横向同性介质,验证了本文关于各向异性反常现象的讨论。

关 键 词：Paradox of anisotropy direct current resistivity time-domain induced polarization FEM 

分 类 号：P631.32[天文地球—地质矿产勘探]