倾斜电各向异性介质大地电磁正演研究  

Magnetotelluric forward study of the tilted electric anisotropic media

作　　者：刘鸿洲[1] 安亚婷 

机构地区：[1]中国地质大学构造与油气资源教育部重点实验室,中国地质大学资源学院,湖北武汉430074

出　　处：《物探与化探》2014年第6期1241-1245,共5页Geophysical and Geochemical Exploration

基　　金：国家自然科学基金项目(40702024);霍英东教育基金会项目(132020)

摘　　要：研究地层电各向异性性质能够圈定沉积地层中的油气储层和与地球动力学过程、地震预报有关的深部线性构造。通过得到的N层倾斜电各向异性介质大地电磁响应公式,在不同的电各向异性系数、地层倾角、倾斜层厚度参数下,对电各向异性倾斜地层模型进行了正演计算。结果表明:当电各向异性系数、地层倾角、地层厚度三者中任一变量改变时,视电阻率曲线的形态基本保持不变,但视电阻率曲线振幅值变化较大;视电阻率曲线对地层倾角参数的变化反应最为敏感;电各向异性系数的增加,能突显薄层电阻率异常。这有助于以后的电各向异性介质大地电磁反演和应用研究。The study of the electric anisotropy properties of strata can delineate oil and gas reservoirs in the strata and the deep linear structure related to geodynamic prCmess and earthquake prediction. On the basis of magnetotelluric response formula in N-layer tilted electric anisotropic media obtained by the authors and under the condition of different electric anisotropy coefficients, dip angles of strata and thicknesses of tilted beds, the authors conducted forward calculation of the model for electric anisotropic tilted strata. The results show that, when any one of the three variables （electrical anisotropy coefficient, dip angle of strata, and depth of strata） is changed, the shape of the apparent resistivity curve remains basically unchanged, but the amplitude value of the apparent resistivity curve varies considerably, that the apparent resistivity curve is most sensitive to the change of the dip angle parameter of strata, and that the increase of the electric anisotropy coefficient can clearly demonstrate the resistivity anomaly of the thin layer. The results achieved by the authors will be helpful to electric anisotropic media magnetotelluric inversion and applied research in future.

关 键 词：倾斜地层 电各向异性 大地电磁测深 电磁响应 正演计算 

分 类 号：P631[天文地球—地质矿产勘探]