萨拉乌苏河流域第四系岩石地层及其时间界限  

The Quaternary Lithostrata in Salawusu River Valley and Their Geochronology

作　　者：李保生[1] 靳鹤龄[2] 祝一志[3] 董光荣[2] 温小浩[1] 

机构地区：[1]华南师范大学地理系,广州510631 [2]中国科学院寒区旱区环境与工程研究所,兰州730000 [3]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,西安710061

出　　处：《沉积学报》2004年第4期676-682,共7页Acta Sedimentologica Sinica

基　　金：国家重点基础研究发展计划(973计划)(2004CB720200);中国科学院知识创新工程重要方向项目(KZCX2SW118);国家自然科学基金(批准号:49971009)资助

摘　　要：根据对位于鄂尔多斯高原毛乌素沙漠东南部边缘萨拉乌苏河流域的米浪沟湾剖面岩石地层划分并结合年代测试结果,提出了如下一些看法1以组为代表的岩石地层单元的形成时间为离石组>150000aB.P.、萨拉乌苏组150000—75000aB.P.、城川组75000—10000aB.P.、大沟湾组—滴哨沟湾组10000—1000aB.P.、范家沟湾组1000aB.P.—现代.2以上岩石单元与黄土高原相同时期层系具有较好的对比关系离石组\萨拉乌苏组、萨拉乌苏组\城川组和城川组\大沟湾组在地质时代上依次与L2\S1(时限为140000aB.P.)、S1\L1(时限为80000aB.P.)和L1\S0(时限为11000—10000aB.P.)大体是等时的.3如以过去全球变化而论,则目前已经可以确切地将米浪沟湾剖面诸岩石单元与深海和大陆冰川最近地质时期的若干氧同位素阶段进行对比,以“”表示为离石组MIS6、萨拉乌苏组MIS5、城川组MIS2～MIS4、大沟湾组+滴哨沟湾组+范家沟湾组MIS1.显然,这一对比关系清楚地说明,我国沙漠万年时间尺度环境演变,与黄土的研究结果一样,在很大程度上受到北半球冰期间冰期气候波动的影响.据此,可以按气候地层进行划分,将离石组、萨拉乌苏组、城川组、大沟湾组+滴哨沟湾组+范家沟湾组的时代分别置于里斯冰期、里斯—玉木间冰期(末次间冰期)、玉木冰期(末次冰期)和冰后期。Based on the lithostratigraphical subdivision with reference to the chronological data in the Milanggouwan section located at Salawusu River Valley of the southeastern margin of Mu Us Desert, Ordos Plateau, China, some ideas have been put forward in the paper: 1 The sedimentary ages of the lithostratigraphical units as indicated by formations in the section are that Lishi Formation was formed at >150000a B. P., Salawusu Formation 150000 75000a B. P., Chengchuan Formation 75000-10000a B. P., Dagouwan and Dishaogouwan Formations 10000 1000a B. P. and Fanjiagouwan Formation 1000a B. P. to present. 2 Geochronologically, the above mentioned lithostratigraphical units can be well correla ted with those in the Loess Plateau, China. Lishi Formation\Salawusu Formation, Salawusu Formation\Chengchuan Formation and Chengchuan Formation\Dagouwan and Dishaogouwan and Fanjiagouwan Formations correspond in succession to L 2 \S 1 (the time limit is 140000 a B. P.), S 1 \L 1 (80000 a B. P.) and L 1 \S 0 (11000 10000 a B. P.). 3 In light of the past global variation, the lithostratigraphical units, at present, can assuredly be compared with the recent several oxygen-isotop stages in the deep sea and continental glacier regions, which are showed by ''as: Lishi Formation  MIS6, Salawusu Formation  MIS5, Chengchuan Formation  MIS2～MIS4, Dagouwan, Dishaogouwan and Fanjiagouwan Formations  MIS1. The correlative relation clearly indicates that the environmental evolution in >10000a scale in Chinese desert, like the Chinese loess, were affected to a great extent by the climatic fluctuations between glacial and interglacial periods in the Northern Hemisphere. According to climate stratigraphy, hereby,the Formations of Lishi, Salawusu, Chengchuan, Dagouwan and Dishaogouwan and Fanjiagouwan may be regarded as Riss Glacial Period, Riss Würm Interglacial Period (Last Interglacial Period), Würm Glacial Period (Last Glacial Period) and Post Glacial Period.

关 键 词：岩石地层 间冰期 第四系 萨拉乌苏河流域 冰后期 氧同位素 剖面 地质时代 鄂尔多斯高原 地质时期 

分 类 号：P534[天文地球—古生物学与地层学] P532[天文地球—地质学]