MIS 3阶段吉兰泰古湖演化的初步研究  

Jilantap Palaeolake Evolution in the MIS 3

作　　者：春喜[1,2] 范育新[3] 夏敦胜[4] 赵辉[4] 

机构地区：[1]内蒙古师范大学地理科学学院,呼和浩特010022 [2]内蒙古自治区遥感与地理信息系统重点实验室,呼和浩特010022 [3]兰州大学西部环境教育部重点实验室,兰州730000 [4]中国科学院寒区旱区环境与工程研究所,兰州730000

出　　处：《干旱区资源与环境》2008年第12期56-61,共6页Journal of Arid Land Resources and Environment

基　　金：中国科学技术部国际合作项目(批准号:2002CB714001);国家自然科学基金(批准号:40761028)资助

摘　　要：本文采用遥感影像分析和差分GPS方法精确测量各级湖岸堤高程，通过OSL定年技术对湖滨沉积物进行年代测定，重建湖泊演化的时空分布格局和环境变化历史。通过大范围的野外调查和测试，结果表明：在吉兰泰盐湖周围存在海拔高度1080～1070m，1060m，1050m，1044m和1035m的5级湖岸堤。在吉兰泰东北70km处乌兰布和沙漠腹地贺日木西尼也存在1080m的古湖岸堤和海拔高度1052m到1035m的长达11km的古沙嘴。各级湖岸堤沉积物由湖滨砂或湖滨砂砾石组成，含有蓝蚬等贝壳体，这些证据是吉兰泰古湖存在和湖面波动的重要标志。通过1080m湖岸堤沉积物的OSL年代测定，确认在MIS3阶段的60ka B．P．前后发育吉兰泰古大湖，此时湖水向东延伸至乌兰布和沙漠腹地，水深达到60m。根据贺日木西尼湖岸堤高程和分布特征来推断，此时的吉兰泰古湖可能与河套古湖产生水源联系。吉兰泰古大湖形成和演化过程，受到区域气候、黄河（内蒙古段）演化和河套古湖的演变以及区域构造运动等诸多因素的影响，需要进一步研究。Jilantai palaeolake evolution in arid regions of Alashan Plateau, Inner Mongolia around MIS 3 was studied. The spatial- temporal distribution pattern of the lake evolvement was reconstructed by accurately measuring the altitudes of each shoreline on the basis of differential GPS and the analysis of remote sensing image, and determi- ning the age of lake sediment by OSL dating method. The results of the spot investigation and the GPS elevation survey in many times indicated that there were 5 grades of shoreline around the Jilantai lake, their altitudes were 1080 - 1070m, 1060m, 1050m, 1044m and 1035m above sea level. In the Herimuxini hinterland of Ulanbuh desert northeast 70km away from Jilantai Lake, there was an ancient shoreline of 1080m above sealeved, and 1052m to 1035m above sea level and 1 lkm long of ancient land spit. Every level of shoreline were composed by the lake beach sand and the lake gravel, including shells and so on. This evidence was the important symbol of the Jilantai lake fluctuation. Through OSL age determination of 1080m level of shoreline deposit confirming that in MIS 3 stage around 60 ka B. P. , there was an ancient big Jilantai Lake. At the time, the lake water extended east to the Ulanbuh ＇desert and the water depth reached 60m. According to the altitude of the Herimuxini hinter- land, ancient Jilantai lake might be related to the ancient Hetao lake by the water source. The climate might be one of the forcing factors of the oscillation of the Jilantai palaeolake level. Nevertheless the evolvement of the Hetao palaeolake and Yellow River evolution and the regional tectonic movements might also be important for the formation of the Paleolake.

关 键 词：MIS 3阶段 吉兰泰古湖 湖岸堤 湖泊演化 

分 类 号：P343[天文地球—水文科学]