青藏高原南部南北地堑系温泉气体地球化学特征与演化过程  

Geochemical characteristics and evolution process for hot spring gas of the north-south graben system in Qinghai−Xizang Plateau

作　　者：全三余 王迎春 唐鑫 周金林 罗璐 宋荣彩[1] QUAN Sanyu;WANG Yingchun;TANG Xin;ZHOU Jinlin;LUO Lu;SONG Rongcai(College of Energy(College of Modern Shale Gas Industry),Chengdu University of Technology,Chengdu,Sichuan 610059,China;State Key Laboratory of Oil and Gas Reservoir Geology and Development Engineering(Chengdu University of Technology),Chengdu,Sichuan 610051,China;New Energy Research Institute,Sinopec Xinxing Company,Beijing 100083,China)

机构地区：[1]成都理工大学能源学院(页岩气现代产业学院),四川成都610059 [2]油气藏地质及开发工程全国重点实验室(成都理工大学),四川成都610051 [3]中石化集团新星公司新能源研究院,北京100083

出　　处：《水文地质工程地质》2025年第2期190-202,共13页Hydrogeology & Engineering Geology

基　　金：国家自然科学基金项目(42130809,42372301);四川省科技计划资助项目(2025ZNSFSC0308)。

摘　　要：目前,对于青藏高原南部单个地热田的水文地球化学演化过程,已有较为清晰的认识,但对于该地区各个地堑系的热泉气体来源和空间特征及演化过程仍缺乏深入了解。通过对青藏高原南部3个地堑(错那—沃卡、亚东—谷露、申扎—定结)的16个热泉气体进行采样与测试,研究分析了地热气体组分、同位素特征、地热气体来源、各地热气体物质含量与状态和地下热储温度的空间关系。以地幔缝合线为分界,识别了青藏高原南部3种类型的热泉气体,取得以下结论:(1)地幔缝合线南北侧的温泉气体演化过程存在明显差异,且青藏高原南部部分温泉气体发生脱气分馏现象;(2)温泉气体中氦、碳主要来源于地壳,氦的运移主要依附于二氧化碳的流动;(3)研究区热储温度存在明显差异,亚东—谷露地堑温度较高(225℃)。研究成果可为阐释青藏高原南部构造与地热气体及地热田的相关性提供参考,同时,对气体地球化学特征及其演化过程的深入探讨,对于深化对地下地质过程的认识以及推动地热资源的高效开发有重要意义。While the hydrogeochemical characteristics of a single geothermal field in Qinghai-Xizang Plateau are well understood,the study of hot spring gases in various graben systems and their spatial characteristics and evolutionary processes,remains insufficiently explored.The study reported 16 hot spring gases from three grabens(Cuona-Woka garben,Yadong-Gulu garben and Shenzha-Dingjie garben)in Qinghai-Xizang Plateau.The composition and isotopic characteristics as well as the sources of hot spring gas were analyzed.Additionally,the relationship between the content of hot spring gas and the reservior temperature was conducted in the three garbens.Three types of gases were distinguished in Qinghai-Xizang Plateau by using the“mantle suture line”as the boundary.The results show that hot spring gases in the north and south sides of the boundary have undergone different evolutionary processes,with some samples in the south showing evidence of degassing and fractionation.The sources of helium and carbon isotopes in the hot spring gases are mainly derived from the crust,and the migration of helium is dependent on the flow of carbon dioxide.There are significant differences of reservior temperature in the three garbens,with a higher temperature(225℃)in the Yadong-Gulu graben.This study provides insights in understanding the relationship between structures,hot spring gases,and geothermal fields in Qinghai-Xizang Plateau.The exploration of gas geochemical characteristics and their evolutionary processes are significant for the understanding of the underground geological processes and the exploitation and utilization of geothermal resources.

关 键 词：地球化学 地热气体 地热温度计 气体同位素 

分 类 号：P314.1[天文地球—固体地球物理学]