摘要
应用同位素地球化学的基本原理和示踪技术,对贡嘎山海螺沟冰川河源区和干流的不同区段,不同时域径流的组成特点及其水文动态变化规律进行分析研究.结果表明:贡嘎山海螺沟冰川河源区水的组成,不同季节、不同时段(早、晚)有明显的变化.夏季晚上的水大约有82.4%是来自冰川区的水,17.6%为非冰川区的径流;早晨中的水来自冰川区的占74.6%,非冰川区径流占25.4%.冰川消融水的最大可占总水量的6.9%~7.8%左右.在冬季时段,冰舌末端排泄水(BCH-1)和冰川水文站(HLG-6)径流的同位素组成均低于底部冰川冰(BCB-2:-16.639‰),显示出严重同位素不平衡的特点,反映了冬季底部冰川消融水在源区水(BCH-1)中的贡献已达很低的程度,而代之以冰川上部占主导优势的雨雪水.这意味着在冬季当地冰川的退缩速度与夏季相比有明显减慢的趋势.示踪表明,在冰川水文站附近区域内存在水的渗漏,夏季可能延伸到倒中桥(HLG-13采样点上方)一带,下渗水通过地下通道,到杉树坪(HLG-2采样点)邻近的区域回补到河道内.
Applying the fundamental and method of isotopic tracing, in this paper the runoff characteristics and hydrological law at the source and trunk stream of Hailuogou valley, Gongga Mountain, are investigated in different sections and at different periods. The preliminary results are as follows: (1) the water component at the source varies obvious in different seasons and different time (morning, evening). At summer evening, water from glacial region accounts for about 82.4% of the total, and water from other account for 17. 6%. In summer, at the morning, water from glacial region account for about 74.6% of total, water from other regions accounts for 25.4%. The maximum of glacial meltwater amount may account for about 6.9% to 7.8% of the total. In winter, the isotope compositions of runoff from the glacial tongue (BCH-1) and Glacier Hydrological Station (HLG-6) are lower than that from glacier bottom (BCB-2 :-16. 639 ), showing an obviously isotopic unbalance. This reflects that in winter, being substituted by dominant rain and snow from upper glacier, the meltwater from glacier bottom accounts for a little of the total, which indicates that the contribution rate of local glacier evidently decreases in winter as compared with that in summer. (2) Below the Glacier Hydrological Station, distinct isotopic abnormity takes place in the region of Daozhongqiao and Shanshuping. The isotopic tracing shows that there exists water leakage near the Glacier Hydrological Station, which may stretch to Daozhongqiao (over sampling location HLG-13) in summer. The leakage water flows through underground channels and supplies the river again in Shanshuping region (sampling location HLG-2). These results may provide very useful clue for studying the shrinking rate of the Hailuogou Glacier, a maritime type glacier.
出处
《冰川冻土》
CSCD
北大核心
2008年第3期365-372,共8页
Journal of Glaciology and Geocryology
基金
国家重点基础研究发展计划(973计划)项目(2005CB422000)资助
关键词
冰川径流
同位素示踪
海螺沟冰川
glacial runoff
isotopic tracing
Hailuogou Glacier
作者简介
尹观(1942-),男,江西永新人,教授,1968年毕业于成都地质学院,主要从事同位素地球化学研究.E-mail:yg@edut.edu.cn