论太湖南岸“地热田”及地热勘查方向  

Taihu Lake's Southern Shore “Geothermal Field” and Geothermal Prospecting Orientation

作　　者：朱华雄 Zhu Huaxiong(Zhejiang Bureau of Coal Geological Exploration,Hangzhou,Zhejiang 310000)

机构地区：[1]浙江煤炭地质局,杭州310000

出　　处：《中国煤炭地质》2018年第2期44-49,共6页Coal Geology of China

基　　金：2013年浙江省地质勘查基金项目"湖州市太湖南岸地热资源勘查";项目编号201005

摘　　要：太湖南岸地区断裂构造极其发育,有北东、北西和东西向三组断裂体系。整个区域都表现出较为明显的地热异常现象,以F-2断层为界分为两个地热分区,西部基岩出露区(Ⅰ区)和东部断陷沉积盆地区(Ⅱ区)。同时在东部区内主要以工程控制的断裂为界划分出"地热田"。"地热田"盆缘断裂发育,盆地区下陷沉积作用明显,上部覆盖有厚度较大的中、新生代盖层,盆地中基底阶梯状断层发育,热储以层状的石炭二叠系灰岩为主,深部热传导为主、对流传导为辅。"地热田"中的井口水温度达42～63℃,水质类型为HCO_3-Na·Ca或Cl·HCO_3-Na型,微咸水,并有3口地热井可供开采利用。总结了区域内的地热地质模型,对比分析了两区地热井的水质成分,显示出东区有更多的深层地下水的补给。建议西部区重点控制深大断裂,寻求断裂带深部的对流型地热资源;东部区工作重点是控制盖层厚度,寻找其下的灰岩热储,同时对"地热田"分布区和北西向区域地热构造异常带作重点研究和控制。Faulted structures are extremely developed in the Taihu Lake’s southern shore area with NE,NW and EW three fracture systems.Geothermal anomalies have shown obviously in the whole area.Taking the fault F-2 as boundary,the area can be partitioned into two geothermal subareas:the west bedrock outcropped subarea I and east fault depression sedimentary basin subarea II.Again,a“geothermal field”can be delineated by engineering controlled faults.The“geothermal field”basin peripheral faults F-2 and F-5 have developed;basin’s sagging sedimentation is obvious.The basin is covered by thick Mesozoic,Cenozoic overburden,and basement step faults developed.Geothermal reservoir is mainly stratified Permo-Carboniferous limestone;heat transfer is dominated by deep heat conduction,supplemented with convection.The wellhead water temperature in the“geothermal field”can be 42℃～63℃as high;water quality type HCO 3-Na·Ca or Cl·HCO 3-Na brackish water,and 3 geothermal wells can be exploited and utilized.The paper has summed up geothermal geologic model;contrastively analyzed geothermal well water qualitative constituents of the two subareas;revealed subarea II has more recharge of deep groundwater.It is suggested that in the subarea I should focusing on deep and large faults control,prospecting for faulted zone deep part convective geothermal resources;in subarea II should focusing on overburden thickness control,prospecting limestone geothermal reservoir under,meanwhile emphasized researching and controlling“geothermal field”area and NW regional geothermal structurally anomalous zone.

关 键 词：地热分区 地热田 勘查方向 

分 类 号：P511.4[天文地球—地质学]