天山黄土记录的古尔班通古特沙漠形成演化  

Evolution of Gurbantunggut Desert Recorded by Tianshan Loess

作　　者：史正涛[1] 宋友桂[2] 安芷生[2] 

机构地区：[1]云南师范大学旅游与地理科学学院,云南昆明650092 [2]中国科学院地球环境研究所黄土与第四纪地质国家重点实验室,陕西西安710075

出　　处：《中国沙漠》2006年第5期675-679,共5页Journal of Desert Research

基　　金：国家自然科学基金(编号:90102017);中国博士后科学重点基金(2002031234)资助

摘　　要：沙漠形成演化是第四纪古气候、古环境研究的重要内容之一。通过位于古尔班通古特沙漠下风向天山北坡河流最高阶地上的厚层风成黄土的形成时代和〉63μm砂含量变化的研究，确定古尔班通古特沙漠最迟在0．8Ma前已经存在。0．8Ma以来沙漠发育经历了基本稳定期（0．8～0．4Ma）、强烈波动扩展期（0．4～0．13Ma）和收缩稳定期（0．13～0Ma）三个阶段。昆黄运动造成东亚大气环流形势的改变，使准噶尔、塔里木盆地等我国西北地区降雨减少，气候显著变干及冬季风强化，盆地中湖泊萎缩消失、大片河湖相松散物质裸露产生的丰富物源为沙漠形成提供了充足的条件，沙漠开始广泛发育，沙漠主体形成。Evolution of desert is one of important aspect of Quaternary paleoclimate and paleoenvironment research. The method applying deposition age of loess and change of loess grain-size 〉63 μm percent to reconstruct the formation of desert is available. In this paper, the result of deposition age and change of grainsize 〉63 μm percent of loess lies on the highest terrace of river in northern margin of Tianshan Mt. shows that Gurbantunggut desert at least has developed as early as 0, 8 Ma. Since then, the desert experienced three phases; they are roughly stable （0. 8-0.4 Ma）, abrupt fluctuation （0.4-0.13 Ma） and contractive stable （0.13-0 Ma）. Kunlun-Huanghe tectonic leads to changes of atmospheric cycle in eastern Asia and decrease of precipitation in the North-western Chinese region such as Junggar and Tarim basin, causing distinctly dry climate and winter monsoon strengthening, shrinking and disappearance of lakes in the basins, bareness of large quantities of loosening substance. The process provides favorable conditions of formation and abroad development of deserts, then the main part of the Gurbantunggut desert development.

关 键 词：沙漠形成时代 沙漠演化 黄土 古尔班通古特沙漠 

分 类 号：P532[天文地球—古生物学与地层学]