摘要
本文运用构造动力学、地热学和地球化学的原理和方法分析了中国东部地热场特征、温泉形成的控制因素及气体组成特征。中国东部地热场具有地域性或分带性的特点 ,其中郯庐断裂带是一高地热活动带 ,这与其所处的大地构造部位和印支运动以来的构造事件密切相关。郯庐断裂带及邻区温泉的发育取决于地质热源体的存在、区域构造、断裂和地下水循环状况、基底和盖层岩石热导率等。温泉中气体成分以N2 为主 (多数在 90 %以上 ) ,CO2 含量变化较大 ,多数在 1.0 0 %以下 ,CH4 和He的含量均小于 1.0 0 % ,Ar多数为 1.0 0 %～ 1.5 0 % ,H2 含量较低 (<0 .1% )。C、O同位素组成变化较大 ,δ13C =- 2 1.33‰～ - 6 .0 2‰ (PDB) ,δ18O =8.85‰～ 38.95‰(SMOW ) ,但两者具有较好的相关性。结果表明温泉气具有多组分、多来源的特征 ,其成因和组成特征决定于现今中国东部的构造应力场及郯庐断裂的活动性质。
The geothermal field characteristics,thermal spring genesis and its gas composition in East China are analyzed by use of the principles and methods of tectonic dynamics,geothermics and geochemistry in the paper.The geothermal fields in East China are of the areal and zonal properties,in which the Tanlu fault zone is an active zone of high geotherm,being closely related to its tectonic portion and to the tectonic events since Indosinian movement.The formation of the thermal springs developed in Tanlu fault zone and its neighbouring regions is connected with existential heat source bodies,regional tectonics,faults and underground circulation,heat conductivities of the basement and caprocks,etc.The gas composition of the thermal springs is mainly the N 2,most of them being more than 90%;the change in CO 2 content is wide,most of them being less than 1.00%;the CH 4 and He are below 1.00%;most of Ar are 1.00%～1.50%;and the H 2 are under 0.1%.The changes in the carbon isotope and oxygen isotope are wide, δ 13 C= -21.33‰ ～-6.02‰(PDB) and δ 18 O=8.85‰～38.95‰(SMOW),a fairly good correlativity,however,is found between both of them.The research results indicate that the gases in the thermal springs are of the characteristics as polycomponent and multisource,which depend on the tectonic stress fields in East China at present and the active propreties of the Tanlu facults.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2000年第6期42-47,共6页
Natural Gas Industry
基金
国家计委"九五"攻关项目! (96 - 110 - 0 1- 0 6 - 0 7)部分成果
