可控源一维正反演技术在地热勘查中的应用

Application and Research of 1D Forward Inversion of Controlled Source audio Magnetotelluric Method in Geothermal Exploration

可控源音频大地电磁测深(CSAMT)法被广泛应用于各类工程勘查中,本文以湖南省溆浦龙田地热勘查为例,首先通过采用一维正演技术,为野外装置参数的确定提供依据,同时利用逼近实测曲线的方式获取模型响应曲线,从而获得地质体模型;再采用一维数据反演,充分的利用野外采集数据信息,获得更好的成果解译。通过反演剖面图与构建的模型对比研究,找出它们共性特征,对物探成果的解译提供一定的理论依据。研究结果表明,采用一维正演技术确定野外装置是有效的,通过正演模型与反演结果对比,表明反演解译成果是可靠的。

Controlled source audio magnetotelluric sounding(CSAMT)is widely used in various engineering exploration.This paper takes prospecting geothermal resources of Xupu Longtian in Hunan province as an example.Firstly,1D forward modeling technique is adopted,It provides a basis for the determination of field equipment parameters,Meanwhile,the response curve of the model is obtained by approximating the measured curve,The geological model is obtained.Then,1D whole area data inversion is used,Make full use of field data to obtain better interpretation.A comparative study was made between the inversion profile and the constructed model.Find out their common characteristics and provide some theoretical basis for the interpretation of geophysical achievements.The results show that the 1D forward modeling technique is effective in determining the field equipment.The comparison between the forward model and the inversion results shows that the inversion interpretation results are reliable.