藏南干旱区湖泊及地热水体氢氧同位素研究  

Hydrogen and Oxygen Isotopes of Lake Water and Geothermal Spring Water in Arid Area of South Tibet

作　　者：肖司 沈立成[1] 王鹏[2] 

机构地区：[1]西南大学地理科学学院,三峡库区生态环境教育部重点实验室,重庆400715 [2]中山大学地理科学与规划学院,广州510275

出　　处：《环境科学》2014年第8期2952-2958,共7页Environmental Science

基　　金：国家自然科学基金项目(41072192);中央高校基本科研业务费专项(XDJK2010B006);高等学校博士学科点专项科研基金项目(20100182120029);岩溶动力学重点实验室开放课题项目(KDL2011-04)

摘　　要：青藏高原水循环过程情况复杂,水体氢氧同位素包含了其重要信息.选取西藏南部干旱区淡水湖、咸水湖及地热水水体为研究对象,分析研究区内不同水体氢氧同位素组成、变化特征、影响因素及水循环过程.结果表明,3种水体均表现出了高海拔地区氢氧同位素组成偏负的特点,淡水湖打加芒错δ18O平均值为-17.0‰,δD平均值为-138.6‰,咸水湖朗错δ18O平均值为-6.4‰,δD平均值为-87.4‰,搭格架地热区热水δ18O平均值为-19.2‰,δD平均值为-158.2‰;受内陆干旱区强烈的蒸发作用影响,湖泊及地热水蒸发线斜率均小于8,氘过量d值均为负值;搭格架地热区热储温度较高,氢氧同位素关系存在氧漂移现象.The condition of water cycles in Tibet Plateau is a complex process,and the hydrogen and oxygen isotopes contain important information of this process. Based on the analysis of isotopic composition of freshwater lake,saltwater lake and geothermal water in the southern Tibetan Plateau,this study investigated water cycling,composition and variation of hydrogen and oxygen isotopes and the influencing factors in the study area. The study found that the mean values of δ^18 and δD in Daggyaima lake water（- 17. 0‰ for δ^18 and- 138. 6‰ for δD）,Langcuo lake water（- 6. 4‰ for δ^18 and- 87. 4‰ for δD） and Dagejia geothermal water（- 19. 2‰ forδ^18 and- 158. 2‰ for δD） all showed negative δ^18 and δD values in Tibetan Plateau by the influence of altitude effects. Lake water and geothermal water were influenced by evaporation effects in inland arid area,and the slope of evaporation line was less than8. Deuterium excess parameters of lake water and geothermal water were all negative. The temperature of geothermal reservoirs in Dagejia geothermal field was high,and oxygen shift existed in the relationship of hydrogen and oxygen isotopes.

关 键 词：湖泊 地热水 氢氧同位素 氘盈余 青藏高原 

分 类 号：X142[环境科学与工程—环境科学]