云南石林盆地东部地热成因模式探讨

Discussion on the geogenetic model of the eastern ShilinBasin, Yunnan

云南石林盆地地热温度呈自西向东逐渐降低的趋势,导致盆地东部地热资源的开发需经过二次加温才能达到可使用的温度。为探究石林盆地东部的高温地热成因和分布特征,采用地质学、水文地质学和地球物理学相关理论,并结合盆地东部物探点绘制的物探剖面,建构三维地质模型,查明石林盆地东部区域地热资源的分布特征,结果显示:石林盆地东部分布多个层状热储层,盖层较薄,保温效果不佳,受盆地东部栖霞茅口组碳酸盐地层的冷水影响,浅部含水层温度较低,而深部水温比浅部温度高。在开发利用过程中可采取井深设计>2500 m、封井位置>1300 m、水温可达50℃的储热和开发模式。研究结果为石林盆地东部高温地热资源开发利用提供了有力的科学依据。

The geothermal temperature in the Shilin Basin of Yunnan is gradually decreasing from west to east,which leads to the development of geothermal resources in the eastern part of the basin after secondary heating to reach the usable temperature.In order to explore the genesis and distribution characteristics of high temperature geothermal in the eastern part of the Shilin Basin,geophysical,hydrogeological and geophysical related theories are used,and the geophysical profiles drawn by the geophysical points in the eastern part of the basin are used to construct a three-dimensional geological model to identify geothermal areas in the eastern part of the Shilin Basin,Distribution characteristics of resources,The results show:There are many layered thermal reservoirs distributed in the eastern part of the Lin Basin,The caprock is thin and the thermal insulation effect is not good,Influenced by the cold water of the carbonate stratum of the Qikou Formation in the eastern Qixia Basin,the shallow aquifer temperature is lower,while the deep water temperature is higher than the shallow temperature.In the development and utilization process,the heat storage and development mode can be adopted with well depth design>2500m,well sealed position>1300m,water temperature up to 50℃.The results provide a strong scientific basis for the development and utilization of high temperature geothermal resources in the eastern Shilin Basin.