江西上犹县莲花塘地热区电性结构及其勘探意义  

Electrical structure and exploration significance of Lianhuatang geothermal zonein Shangyou County,Jiangxi Province

作　　者：谢文 陈辉 余辉 Xie Wen;Chen Hui;Yu Hui(School of Geophysics and Measurement-control Technology,East China University of Technology,Nanchang 330013,China;State Key Laboratory of Nuclear Resources and Environment,Nanchang 330013,China)

机构地区：[1]东华理工大学地球物理与测控技术学院,江西南昌330013 [2]核资源与环境国家重点实验室,江西南昌330013

出　　处：《资源环境与工程》2025年第2期191-196,共6页Resources Environment & Engineering

摘　　要：江西赣州地区经历了加里东期和燕山期岩浆活动,区内地热资源分布广泛。赣州外围的上犹县莲花塘地热区具有较好的地热资源勘探潜力,但其开发程度较低。通过布设4条覆盖莲花塘地热区的可控源音频大地电磁测深(CSAMT)剖面,并采用非线性共轭梯度反演算法对测量的标量CSAMT数据进行二维反演,获得了研究区地下500 m以浅的电性结构模型。结果显示,研究区纵向上主要呈现2层电性结构,其中浅层低阻为白垩系红层,深部高阻为寒武系地层;横向上主要呈现为高—低—高的电阻率分布特征。结合已有地质资料,推测高低阻梯度带及其东侧的低阻异常为NE向F_(2)断裂和含水破碎带的电性反映;F_(2)断裂是研究区的主要控热构造,沿着该断裂发育的含水破碎带很可能是有利的地热储层。在莲花塘地区开展的地球物理工作查明了赣州外围地热区主要地层分布与控热构造的展布特征,为圈定类似地热储层有利远景区提供了借鉴。The Ganzhou area in Jiangxi Province has experienced magmatic activity during the Caledonian and Yanshanian periods,and geothermal resources are widely distributed in the area.The Lianhuatang geothermal area in Shangyou County,located on the outskirts of Ganzhou,has good potential for geothermal resource exploration,but its level of development is relatively low.Four controlled-source audio-frequency magnetotellurics(CSAMT)profiles covering the Lianhuatang geothermal area were deployed,and a nonlinear conjugate gradient inversion algorithm was used to perform two-dimensional inversion on the measured scalar CSAMT data,obtaining an electrical structure model of the study area within 500 meters underground.The result indicate that the study area mainly presents two layers of electrical structure vertically.Among them,the shallow low resistance is Cretaceous red beds,and the deep high resistance is Cambrian strata.The horizontal electrical structure in this region mainly presents a high low high resistivity distribution characteristic.Based on existing geological data,it is speculated that the high low resistance gradient zone and the low resistance anomaly on its east side are electrical reflections of the northeast trending fault F_(2)and the water bearing fracture zone.The fault F_(2)is the main controlling thermal structure in the study area,and the water bearing fracture zone developed along this fault is likely to be a favorable geothermal reservoir.The geophysical work carried out in the Lianhuatang area has identified the distribution characteristics of the main strata and controlling structures around the Ganzhou geothermal area,providing reference for delineating favorable prospective areas for thermal reservoirs in similar geothermal areas.

关 键 词：地热 地球物理勘查 可控源音频大地电磁法 二维反演 

分 类 号：P314.1[天文地球—固体地球物理学] P631.3[天文地球—地球物理学]