摘要
为了解起伏地表对复电阻率法数据的影响,发展了起伏地表条件下复电阻率法2.5维有限元数值模拟方法。经数值模拟结果与解析解对比表明,该模拟方法在计算精度上得到了较满意的结果;几种常见纯地形异常的数值结果表明:起伏地形对复电阻率法数据的畸变特征与地形坡度大小以及地形分布范围有很强的相关性,坡度越大,地形影响越为剧烈;坡度角为45°的山脊地形、山谷地形和斜坡地形所引起的复电阻率法实分量异常分别达到背景值的21.2倍、3.9倍和3.4倍,虚分量异常分别达到背景值的2.3倍、2.2倍和2.1倍,振幅异常分别达到背景值的21.2倍、3.9倍和3.4倍;而相位受地形影响非常微弱。这些工作为复电阻率法的地形改正和反演奠定了基础。
This thesis,in order to understand the influence caused by the undulate topography on the data of the complex resistivity method,develops the 2.5-D finite-element forward modeling method of the complex resistivity method in conditions of the undulate topography.From the comparison between the result of numerical modeling and the analytical solution,this modeling method has made a satisfactory result in terms of the calculation precision;from the numerical simulation results of several common terrains,it shows that the undulate topography's effect on the complex resistivity method has a fairly strong correlation to the gradient and distribution of topography.The greater the gradient is,the more fiercely the effect o{ terrain functions.For the 45° terrains of ridge,valley and brae,the abnormal real component o{ complex resistivity caused by them comes respectively to background values of 21.2 times and 3.9 times and 3.4 times;the abnormal imaginary component reaches respectively to background values of 2.3 times and 2.2 times and 2.1 times;and abnormal amplitude,respectively,21.2 times and 3.9 times and 3.4 times.However,phase gets extremely weak impact of topography.These has laid a foundation for the topographic correction and inversion algorithm of the complex resistivity method.
出处
《物探化探计算技术》
CAS
CSCD
2013年第1期1-9,15,共9页
Computing Techniques For Geophysical and Geochemical Exploration
基金
国家重大科学仪器设备开发专项(2011YQ50060)
国家863重点项目(2007AA060601)
国家重点新产品计划项目(2011FU125Z16)
中国地质调查项目(1212011120193)
