【作者】 张致付； 程志平； 阮百尧； 李泽林；

【Author】 ZHANG Zhi - fu, CHENG Zhi - ping, RUAN Bai - yao(Institute of Geology and Geophysics, CAS, Beijing 100029;Department of Resources and Environmental Engineering, Guilin Institute of Technology, Guilin 541004)

【机构】 中国科学院地质与地球物理研究所； 桂林工学院资源与环境工程系；

【摘要】 三堆电阻率测深数据采用Zohdy方法近似反演,正演计算采用有限单元法,反演初始模型由测量视电阻率数据给出,通过比较实测视电阻率值和预测模型计算的视电阻率值对数差来修改模型网格电阻率。为了解决任意电极距测深数据的反演,采用大、小双网格剖分,大网格反映地下电性分布情况,小网格用于实际有限元正演计算。文章对加5%随机噪声的模型理论视电阻率测深断面数据和实测视电阻率测深断面数据进行反演。结果表明该反演方法需要的內存小、计算量少,并能够取得很好的反演效果。更多还原

【Abstract】 Zohdy method has been used for the approximate inversion of three - dimensional resistivity sounding data; while the forward solutions have been obtained with FEM. The initial electrical parameters of the earth are obtained from observed data or forward data of the earth model and modified according to the logarithmic difference between observed data and the theoretical data calculated with FEM. Two kinds of grid system have been employed to solve the problem arose from the arbitrary electrode - spacing. The big grid pictures resistivity distribution of earth model, while the small one is used to define the elements in forward solution. Finally, both the theoretical data, with 5% random noise added, obtained from three-dimensional earth model and the observed data have been inversed. It shows that less storage and computation time are needed for calculation than other inversion methods, and the results are quite acceptable.更多还原