乌鲁木齐河源1号冰川冰芯δ^(18)O记录的现代环境过程分析  

PRESENT ENVIRONMENTAL PROCESSES OF ICE CORE δ^(18)O RECORDS OF THE NO.1 GLACIERS AT THE HEADWATER OF URUMQI RIVER, XINJIANG, CHINA

作　　者：侯书贵[1] 秦大河[1] 李忠勤[1] 皇翠兰[1] 

机构地区：[1]中国科学院兰州冰川冻土研究所冰芯与寒区环境实验室,兰州730000

出　　处：《地球化学》1998年第2期108-116,共9页Geochimica

基　　金：国家自然科学基金!49571020;中国科学院天山冰川观测试验站基金!95001

摘　　要：据乌鲁木齐河源地区一个完整年周期的大气降水样品、1号冰川连续雪坑样品及浅冰芯样品的实测δ18O资料，初步探讨冰芯δ18O记录的形成过程和影响因素，以及δ18O与气温之间的关系转变。结果表明本区大气降水中的δ18O与气温之间存在显著的正相关关系，但由于冬季雪层内水汽运移作用和风力导致积雪的重新分布作用，以及夏季雪层中融水渗浸作用等积雪沉积后的影响，1号冰川冰芯的δ18O记录与实测气温记录之间存在明显的差异，即研究区域的冰芯δ18O记录不再具有明显的温度指标意义。Analyses of stable oxygen isotope in precipitation samples during June, 1995 to June, 1996, in snowpit samples during the winter of 1995-1996 and during the summer of 1996, and in shallow ice core samples retrieved in May, 1996 from the headwater of Urumqi River are presented in this paper. The results indicate that:1. A marked positive correlation between temperature and δ18O values in precipitation is shown in the studying regions.2. Smoothing effect by the vapour movement within the snowpacks and redistribution of snowpacks by wind-blowing are the main factors that can alter the original δ18O profiles during winter. During the summer, the main affecting factor is the melt-water percolation processes.3. Significant difference can be found between ice core δ18O records and monitored temperature history nearby the glacier, which suggests that the post-deposition processes have changed the original temperatUre significance of δ18O in precipitation to a certain degree.

关 键 词：降水 Δ^18O 环境过程 乌鲁木齐河源 冰川 冰芯 

分 类 号：P597[天文地球—地球化学] P426.612[天文地球—地质学]