自然电位方法在地热勘探中的应用研究

发布时间：2018-06-10 13:59

本文选题：自然电位方法 + 过滤电场　；参考：《吉林大学》2015年硕士论文

【摘要】：在地热勘探中，地球物理方法主要探查含地热流体的地质和构造环境或是探查流体分布规律。地下水流动产生的过滤电场是自然电场法在地热勘探中的应用主要基础。用经验公式建立过滤电场和地下水流动的关系，并应用于自然电场数据反演地下水分布和流体属性参数。自然电场数据梯度采集方式有数据不稳定性，干扰较多，误差较大等缺点。文中采用测线形成闭合圈的方法，进行闭合差改正，可以统一全区零电势，并提高数据质量。地表测量自然电场不仅是场源(电流源)的响应，也是地下介质电导率分布的响应。论文通过给出一定的模型渗透率的约束，减少源的位置不确定性，，建立更合理的电阻率模型，提高自然电场反演精度。在地热勘查中，在综合其他地球物理方法探测结果基础上，建立自然电位模拟正演模型，进一步提高反演结果的准确性。以长春净月南部区域地热探测为实例。采用可控源大地电磁剖面作为电阻率模型，并结合地质资料给出渗透率模型作为约束，进行自然电场的反演，得出地下水的流速、流向的信息，对地热勘探具有指导意义。
[Abstract]:In geothermal exploration, geophysical methods are mainly used to explore the geological and tectonic environment of geothermal fluids or the distribution of geothermic fluids. The filter electric field generated by groundwater flow is the main basis of the application of natural electric field method in geothermal exploration. The relationship between filtering electric field and groundwater flow is established by empirical formula, and applied to the inversion of groundwater distribution and fluid attribute parameters from natural electric field data. Large errors and other shortcomings. In this paper, by using the method of forming closed circle by measuring line, the correction of closing difference can be made, which can unify the zero potential of the whole area and improve the data quality. The natural electric field measured on the ground is not only the response of the field source (current source), It is also the response of conductivity distribution in underground media. In this paper, the model permeability constraints are given to reduce the uncertainty of source location, and a more reasonable resistivity model is established to improve the accuracy of natural electric field inversion. In geothermal exploration, based on the results of other geophysical methods, a forward model of natural potential simulation is established to further improve the accuracy of the inversion results, taking the geothermal exploration in the south of Jingyue in Changchun as an example. The magnetotelluric section of controllable source is used as resistivity model and permeability model is given as constraint in combination with geological data. The inversion of natural electric field is carried out, and the information of velocity and direction of groundwater flow is obtained, which is of guiding significance for geothermal exploration.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P631.3;P314

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