青藏高原东北部冬给措纳湖湖区冰缘环境探讨  

A Study of the Periglacial Environments around the Donggi Cona Lake on the Northeastern Tibetan Plateau

作　　者：罗栋梁[1] 金会军[1] 杨思忠[1] Bernd Wünnerman 

机构地区：[1]中国科学院寒区旱区环境与工程研究所冻土工程国家重点实验室,甘肃兰州730000 [2]南京大学地理与海洋科学学院,江苏南京210093

出　　处：《冰川冻土》2010年第5期935-940,共6页Journal of Glaciology and Geocryology

基　　金：国家自然科学基金创新群体项目“冻土与寒区工程”(40821001)资助

摘　　要：冬给措纳湖位于青藏高原多年冻土区东北部,湖区高寒沼泽、冰缘环境、冻土分布及其演化在全球气候变暖条件下,有其自身特点.为探讨冬给措纳湖湖区冻土分布及冰缘环境,2009年5月9—26日,对冬给措纳湖进行了考察,发现冻融草丘、冻胀丘遗迹、寒冻裂缝、热融洼地、古冻融褶皱等现代冰缘及古冰缘现象在湖区普遍存在.湖东、西岸的沼泽湿地中,热喀斯特发育明显,形成热融洼地和冻融草丘.湖北岸阶地及草场中存在零星和岛状冻土,经钎探表明,当时融化深度为0.3～0.8m,0.4m深度处冻土有胶结冰发育.湖东冲积平原的沼泽湿地中,冻融草丘和热融洼地存在;冻胀丘遗迹、寒冻裂缝在沼泽湿地边缘泥炭覆盖地存在.湖北岸二级阶地剖面发现古冻融褶皱.The Donggi Cona Lake is located at the northeastern marginal of the Tibetan Plateau.Different from the high elevation permafrost in other parts of the Tibetan Plateau,the distribution of permafrost and its relation to alpine meadows and periglacial environments have their unique features.To further study the permafrost and periglacial landforms around the Donggi Cona Lake,a Sino-Germany joint team investigated the lake and adjacent regions during the period from 9 to 26 May 2009.Earth hummocks,relics of palsa,frost cracks,thermokarst depressions,and cryoturbation,and other periglacial manifestations were identified.Thermokarst features well developed on the eastern and western lake shores,and the sporadic and patchy permafrost was identified.The thawed depths were found to be 0.3～0.4m during the investigation,and cement ice was visible at the depth of 0.4m.Earth hummocks and thermokarst depressions were identified in the wetlands on the piedmont alluvial fan in the east of the lake.The palsa remnant and frost cracks were located on the margin of these wetlands.A cryoturbation was discovered at the edge of the second terrace on the north lakeshore.

关 键 词：冬给措纳湖 冰缘环境 岛状冻土 泥炭丘遗迹 冻融褶皱 冻融草丘 

分 类 号：P642.14[天文地球—工程地质学]