冰碛曝光问题的沉积学探讨——以帕米尔东坡阿依直苏冰川为例  

DISCUSSIONS ON EXPOSURE PROBLEMS OF GLACIAL DEPOSITS BEFORE BURIED——BASED ON THE AYIZHISU GLACIER IN PAMIR

作　　者：周尚哲[1] 欧先交[2] 王杰[3] 郑景雄[1] 

机构地区：[1]华南师范大学地理科学学院,广州510631 [2]嘉应学院地理科学与旅游学院,梅州514015 [3]兰州大学资源与环境学院西部环境教育部重点实验室,兰州730000

出　　处：《第四纪研究》2012年第1期39-45,共7页Quaternary Sciences

基　　金：国家自然科学基金项目(批准号:40771049;41171014和40901011)资助

摘　　要：针对冰川沉积系列细砂粉砂在埋藏前的曝光问题,笔者等人在帕米尔阿依直苏冰川做了观察。本文结合这些观察结果从沉积学角度讨论冰川沉积系列在产生、搬运、沉积过程中的曝光问题,并参考前人研究,将各类冰川沉积进行归纳。认为组成冰碛3个来源的细粒物质中,风成的全部曝光、岩壁风化碎屑部分曝光、冰川侵蚀岩屑不曝光;3个沉积系列中,冰水沉积完全曝光、冰川接触沉积中冰砾阜完全曝光、蛇形丘基本不曝光;冰碛物在沉积过程中,冰面融出碛基本上曝光、冰下滞碛和融出碛不曝光。本文根据分析,给出了冰川沉积系列曝光评估参考值。We carried through an observation to till depositional processes of Ayizhisu Glacier in the eastern Pamir in order to understand the exposal problem of glacial deposits before burial. In this paper we discuss the exposure possibilities of glacial deposit series during the processes of their production, transportation and deposition based on the observations and sedimentology. The till materials come from by three ways, i. e. the weathered debris from bedrock,the eroded debris by glacier ice and eolian deposit. Of which the eolian dust and a large portion of the weathered debris could be exposed to daylight, whereas glacial eroded debris could not. Among the three kind of glacial deposits,the glaciofluvial deposit can be completely exposed. For till deposit,supraglacial melt out till could be basically exposed,whereas lodgement till could not. For ice contact deposit, sand in kame could be completely exposed and esker could not. Based on analysis we presented the estimated values for different glacial deposits.

关 键 词：冰川沉积 信号归零 阿依直苏冰川 

分 类 号：P534.63[天文地球—第四纪地质学] P512.41[天文地球—古生物学与地层学]