综合物探方法在内蒙古某地区地热资源调查中的应用研究

Application research of comprehensive geophysical exploration method in geothermal resources survey in a region of Inner Mongolia

随着经济的快速发展和人们对环境保护意识的增强,地热作为一种天然、清洁、可再生的绿色能源受到越来越多的关注。在分析内蒙古某地区构造和水文地质条件的基础上,认为该区具有较好的地热储存及输送通道,继而在该地区同时开展二维地震勘探和音频大地电磁2种地球物理方法。利用地震勘探波阻抗差异,进行地质分层解释;利用大地电磁测深法的电阻率差异和体积效应,确定含水层和热储层位置和厚度。通过综合对比解释,认为该地区内电阻率偏低与砂岩孔隙、裂隙中富含水密切相关,确定新近系的中—上新统地层是该地区良好的含水层,该地层厚度为1600 m,结合区域地热井资料确定了主要储热层,因此2种不同物探方法在地热资源调查综合应用中取得了较好效果。

With the rapid development of economy and the increase of people′s awareness of environmental protection,geothermal as a natural,clean and renewable green energy has received more and more attention.Based on the analysis of structural and hydrogeological conditions in a certain area of Inner Mongolia,it was considered that there was a good geothermal storage and transportation channel in this area,and then two geophysical methods of 2D seismic exploration and audio magnetotelluric were carried out in this area.The difference of seismic wave impedance was used to explain geological stratification.The resistivity difference and volume effect of magnetotelluric sounding were used to determine the location and thickness of aquifer and thermal reservoir.Through comprehensive comparison and interpretation,it was believed that the low electrical resistivity in the area was closely related to the high water content in sandstone pores and fractures.It was determined that the Middle Upper Neogene strata of the Neogene were good aquifers in the area.The thickness of the formation was about 1600 m,and the main thermal reservoir was determined by combining the regional geothermal well data.Therefore,the two different geophysical exploration methods have achieved good results in the comprehensive application of geothermal resources investigation.