冰雪溶融的同位素效应及氘过量参数演化——以四川稻城水体同位素为例

Isotopic Effect and the Deuterium Excess Parameter Evolution in Ice and Snow Melting Process:A Case Study of Isotopes in the Water Body of Daocheng,Sichuan Province

水体同位素组成的变化实际上是依存于环境变化的一种综合性反应。不同季节高原高山冰雪的溶融 ,可以明显地影响地表径流和浅层地下水的同位素组成及氘过量参数的变化。了解这一特有的自然背景所引起的同位素分馏现象 ,探索其形成过程及演化机理 ,对于评价一个地区环境、气候及水资源的关系 ,其重要性是不言而喻的。本文以四川稻城地表径流和温泉水的同位素组成为例 ,主要介绍了不同季节高原高山冰雪溶融背景条件下地表径流和温泉水同位素组成及氘过量参数变化规律 ,结合当地的自然背景及气候条件 ,着重分析讨论了冰雪溶融过程中的同位素效应及氘过量参数演化过程及原因。

The variation of water isotope composition is actually an integrated reaction depending on the change of environment. The ice and snow melt of different seasons in high mountains can obviously affect the variation in isotope composition and deuterium excess parameters of surface flow and shallow groundwater. The knowledge of the isotopic fractionation caused by this special natural background and the exploration of its formation and evolution are extremely important in estimating the relationship between the environment,climate and water resources in a certain area. With the isotope composition of surface flow and shallow groundwater in Daocheng of Sichuan as an example,this paper deals mainly with the variation regularity of the isotope composition and the deuterium excess parameters of surface flow and hot-spring under the condition of ice and snow melt in high mountains during different seasons. The isotope effect and the deuterium excess parameter evolution in the process of ice and snow melting are also discussed in detail.