玉龙雪山冰川稳定同位素分馏冬夏对比

Comparisons of Stable Isotopic Fractionation in Winter and Summer at Baishui Glacier No. 1, Mt. Yulong

利用玉龙雪山白水1号冰川区冬季和夏季表面积雪、雪坑、融水以及白水河河水中!18O资料,对比分析了冬季和夏季我国典型季风温冰川系统内稳定同位素分馏行为的差异。分析结果表明,夏季冰川系统内各水体相变过程中稳定同位素分馏程度均比冬季强烈,指示出夏季季风海洋型冰川强烈消融的特点。另外,不论是冬季还是夏季,从表面积雪到融水再到由融水补给的河流,"18O垂直变化梯度依次增大,反映了从固态降雪向冰川融水补给的河流河水转换过程中,稳定同位素分馏程度逐渐增强,体现了沉积后过程对海洋型冰川区同位素记录的影响具有空间差异性。

Based on the data of δ^18O in surface snow, snow pits, meltwater and the glacier-fed river water at Baishui glacier No. 1, Mt. Yulong, the isotopic fractionation behaviors in the typical monsoonal temperate glacier system in winter and summer were compared. The results indicate that the isotopic fractionation degree in summer is larger than that in winter, suggesting that the snow/ice melting is more intense in summer. Moreover, whenever it is in winter or summer, from surface snow to meltwater, and to glacier-fed river water, the gradient of δ^18O with altitude gradually increases. It shows that the degree of isotopic fractionation gradually strengthens when surface snow being converted into meltwater and finally into glacial river water, which suggests that the influence of post-depositional processes on δ^18O gradient in the monsoonal temperate glacier region differs spatially.