龙门山断裂带温泉水文地球化学特征  

Hydrogeochemical Characteristics of the Hot Springs in the Longmenshan Fault Zone

作　　者：颜玉聪 刘峰立 郭丽爽 周晓成[1] 欧阳澍培 李静超 王万丽 YAN Yucong;LIU Fengli;GUO Lishuang;ZHOU Xiaocheng;OUYANG Shupei;LI Jingchao;WANG Wanli(Institute of Earthquake Forecasting,China Earthquake Administration,Beijing 100036,China;National Institute of Natural Hazards,Ministry of Emergency Management,Key Laboratory of Crustal Dynamics,China Earthquake Administration,Beijing 100085,China)

机构地区：[1]中国地震局地震预测研究所,北京100036 [2]应急管理部国家自然灾害防治研究院中国地震局地壳动力学重点实验室,北京100085

出　　处：《地震研究》2021年第2期170-184,共15页Journal of Seismological Research

基　　金：国家重点研发计划(2017YFC1500501);国家自然科学基金面上项目(41673106);中国地震局地震预测研究所基本科研业务费(2017IES010205,2016IES010304,2018IEF010104,2020IEF0604,2020IEF0703)联合资助。

摘　　要：对地震活动强烈地区进行水文地球化学监测可以很好地获取与地震相关的深部流体地球化学信息。通过研究龙门山断裂带及其周围13个温泉及观测井的水文地球化学特征,建立该断裂带温泉水文循环模型,揭示其水化学变化与地震活动的关系。结果表明:(1)龙门山断裂带温泉水主要来自其周围0.8~3.2 km高山的大气降水;(2)温泉水化学类型沿龙门山断裂从北到南、从西到东依次为重碳酸型、硫酸型、氯化物型,温泉水的循环深度、水岩反应程度及微量元素富集因子不断增加;(3)在汶川MS8.0地震、芦山MS7.0地震发生后,震中距200 km以内的温泉的离子组分呈下降趋势,这可能是在震后愈合过程中,龙门山断裂内部渗透性减弱、水岩反应程度衰减所致。Hydrogeochemical Monitoring in the regions with strong earthquake activities would facilitate the obtaining of the geochemical information about deep fluids correlated to seismic anomalies.In this paper the hydrogeochemical characteristics of 13 hot springs(wells)in the Longmenshan Fault Zone were investigated, so as to establish the hydrogeochemical cycle model of the hot springs and reveal the relationship between hydrogeochemical variations and seismic activity in the Fault Zone.The results show that:(1)The hot springs in the Longmenshan Fault Zone were recharged by the meteoric water at elevations ranging from 0.8 to 3.2 km.(2)The chemical types of the hot springs from north to south, and from west to east along the Longmenshan Fault Zone were respectively carbonic acid, sulfuric acid and chloride.Likewise, the circulation depth of spring water deepened;the water-rock reaction intensified;and enrichment factors of the trace element of the hot springs continuously increased.(3)After the Wenchuan MS8.0 earthquake and the Lushan MS7.0 earthquake, the dissolved hydrochemical composition got declining in hot springs within the epicenter of 200 kilometers, which could be the result of the permeability decrease and the attenuation of water-rock reaction inside the fault in the healing process of the Longmenshan Fault after earthquake,

关 键 词：温泉 水文地球化学 地震 龙门山断裂带 

分 类 号：P314.1[天文地球—固体地球物理学]