平顶山矿区地热地质条件及其成因分析  

Analysis of geothermal geological conditions and its genesis in Pingdingshan mining area

作　　者：李延河[1,2] 万志军 于振子[3] 王朱亭 张波 张源[2] LI YanHe;WAN ZhiJun;YU ZhenZi;WANG ZhuTing;ZHANG Bo;ZHANG Yuan(Pingdingshan Tianan Coal Mining Co.,Ltd.,Pingdingshan 467099,China;China University of Mining and Technology,Xuzhou 221116,China;Institute of Coal Mining and Utilization Research Pingdingshan Tianan Coal Mining Co.,Ltd.,Pingdingshan 467099,China)

机构地区：[1]平顶山天安煤业股份有限公司,平顶山467099 [2]中国矿业大学矿业工程学院,徐州221116 [3]平顶山天安煤业股份有限公司煤炭开采利用研究院,平顶山467099

出　　处：《地球物理学进展》2023年第2期551-561,共11页Progress in Geophysics

基　　金：国家自然科学基金项目(51674242,52074266);江苏省双创博士计划(JSSCBS20211229)联合资助。

摘　　要：地热资源作为清洁可再生能源之一,合理的开发地热能有助于国家“双碳”目标的实现,而正确认识区域地热地质条件及其成因是地热资源开发利用的前提.平顶山矿区位于构造隆起区且区内岩溶含水层广泛发育,基岩起伏产生的热折射效应及岩溶层内地下水对流共同造成该区浅表存在温度异常,沉积盖层段的地温梯度值高达45.0℃/km.本文以7口钻井测温曲线和254块样品热物性资料为基础,分析了该区地温场特征,并结合区域典型地层剖面,对岩溶层内流体对流对地层温度影响的开展水热耦合研究,并通过热模拟分析构造界面两侧热物性差异产生的热流侧向汇聚作用对浅表聚热的作用大小.结果表明:平顶山矿区地温梯度值范围在8.0~66.9℃/km之间,对应的热流值范为31.0~135.0 mW/m^(2),且地温场分布呈明显的分带性,构造凸起区相对于四周凹陷区地层温度、地温梯度、热流值较高;水热耦合模拟显示,在补给区,随着冷水沿着地表出露的岩溶含水层的不断下渗,地层温度越来越低,在排泄区,补给区冷水经过深部循环加热后向上排泄,进而加热周边岩层;其次,导水断裂可以深刻改变地层温度场的分布,是地层温度下降或上升的分界线;基岩起伏产生的热折射效应是造成矿区构造隆起区温度较高的主要原因,因热折射效应在1.0 km范围内所造成的地温梯度值的波动在6.8℃/km左右,进而所产生的热流扰动在12.3 mW/m^(2),是造成该区局部热异常的主要原因之一.As one of the clean and renewable energy,the reasonable development of geothermal energy can help to achieve the goal of carbon peak and carbon neutralization,and correctly understanding the regional geothermics geology and its genetic mechanism are the basis for the efficient utilization of the geothermal resources.Pingdingshan mining area is located in the tectonic uplift area,where karst aquifers are widely developed.The thermal refraction effect caused by bedrock fluctuation and groundwater convection in the Karst layer cause the temperature anomaly on the shallow surface,and the geothermal gradient within sedimentary section is as high as 45.0℃/km.Based on the temperature measurement from 7 wells and thermophysical property data of 254 samples,characteristics of the geothermal field in this area was analyzed,and according to the typical regional formation profile,influence of groundwater convection in Karst layer on the formation temperature was carried out by the hydrothermal coupling.Effect of the lateral heat flow accumulation caused by the difference of thermophysical properties on both sides of the structural interface was also studied.Results show that the geothermal gradient value in Pingdingshan mining area ranges from 8.0 to 66.9℃/km,and the heat flow value ranges from 31.0 to 135.0 mW/m^(2).The geothermal field distribution shows obvious zoning characteristics,which the formation temperature,geothermal gradient and heat flow value in the structural uplift area are higher than those in the surrounding depression area.The hydrothermal coupling simulation shows that in the recharge area where the karst aquifer exposed on the surface,the infiltration of cold water caused the formation temperature becoming lower.In the discharge area,the cold water in the recharge area is discharged upward after deep circulating heating,and heating the surrounding rock.The water conducting fault can profoundly change the distribution of formation temperature,which is the boundary for the decline or rise of formation

关 键 词：大地热流 钻井测温曲线 地下水 地温场 平顶山矿区 

分 类 号：P314[天文地球—固体地球物理学]