Re-determination on the Sedimentary Age of Salawusu Formation
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摘要: 重新认识我国北方地区晚更新世河湖相标准地层——萨拉乌苏组的形成时代，对于萨拉乌苏组与马兰黄土的关系，与冰期气候对比等具有重要意义。笔者近年来根据野外层位对比和地层沉积相的划分，采用绝对年代控制，并结合黄土－古土壤序列研究的最新成果，初步建立了可以与黄土、深海沉积记录和冰期气候波动对比的萨拉乌苏组地层序列。认为河湖相沉积的萨拉乌苏组形成于约１４００００～７００００ａ.Ｂ.Ｐ.的末次间冰期，大致与深海氧同位素第５阶段对应，与黄土高原古土壤Ｓ１发育同期。城川组风成细砂形成于约７００００～１００００ａ.Ｂ.Ｐ的末次冰期，与黄土高原的马兰黄土是同期异相地质体.Abstract: The Salawusu River area is one of the standard sections of the Late Pleistocene strata in North Chi-na.However, there have been a lot of different views about the strata since the establishment of alawusu Formation, especially in the aspects of sedimentary facies, stratigraphic data and its climate sig-nificance.According to the stratigraphic subdivision, age dating and the analysis of the sedimentary fa-cies, the following recognitions can be gained: 1 The original Salawusu Formation could be further divided into Lishi Loess interbeded with sandysediments(Q22 ), Salawusuu Formation(Q,13 ), Cheng-chuan Formation(Q2,3 ), Dagouwan Formation (Q4 )and Dishaogouwan Formation(Q34 ).2 Salwusu Formation is mainly a fluvial-lacustrine deposit corresponding to the Stage 5 of deep seainδ18O and formed between about 140- 70 Ka.BP.Chengchuan Formation is mainly fossil aeolian sands,with some lacustrine silty-clay in the middle part, correspording to Stages 2- 4 of deep sea inδ18O andformed between 70- 10 Ka.BP.Dagouwan Formation is lacustrine sediments and black-paleosoil, indi-cating the warm-humid climate and formed in the middle-early period of Holocene.Dishaogouwan For-mation is mainly sub-loess and aeolian sands, representing the cold-dry climate and being believed to be-long to the late Holocene.3 As a fluvial-lacustrine sedimentary stratum, Salawusu Formation is quite different from its upperChengchuan Formation both in geochronology, lithology and sedimentary facies and in palaeontology.Chengchuan Formation and Malan Loess belong to heteropic deposits(sandy and loessic facies) formedcontemporaneously under the same wind action.4 As a flurial-lacustrine-aeolian-sand sequence by observing the Dishaogou profile in the SalawusuRiver area,its climatic records can compete with the records of loess and deep sea deposits, they may bedivided into 5 climatic periods just by oxygen isotope.It is suggested that the climatic change of this re-gion during the last interglacial period is synchronous withthat of the whole earth.
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Key words:
- Salawusu Formation /
- stratigraphic division /
- edimentary age
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[1] (1) Teihard de chardin P and Licent E.On the discovery of apalaeoilthic in No rth China.Bull Geol, Soc, China, 1924, 3(1):45～50.
(2) P德日进, E · 桑志华.陕西北部黄土地带与河套东西南之理想剖面.中国地质学会志, 1924, 3(1).
(3) 李保生,董光荣,高尚玉等.鄂尔多斯萨拉乌苏河地区马兰黄土与萨拉乌苏组的关系及地质时代问题.地质学报, 1987, 61(3):218～230.
(4) 袁宝印.萨拉乌苏组的沉积环境及地层划分问题.地质科学,1978, (3): 220～224.
(5) 原思训,陈铁梅,高世君.用铀子系法测定河套人和萨拉乌苏文化的年代.人类学学报, 1983, (2): 90～94.
(6) 祁国琴.内蒙古萨拉乌苏河流域第四纪哺乳动物化石.古脊椎动物与古人类, 1975, 13(4): 239～249.
(7) 周昆叔,黎兴国,邵亚军.内蒙古萨拉乌苏河流域冰缘期划分及其意义,见: 史前地震与第四纪地质文集.西安: 陕西科技出版社, 1982, 149～153.
(8) 黎兴国,刘光联,许国英等.河套人及萨拉乌苏文化的年代.见:第一次全国 14 C学术会议文集,北京: 科学出版社, 1984, 141～143.
(9) 郑洪汉.中国北方晚更新世河湖相地层与风积黄土.地球化学,1989, (4): 343～351.
(10) 董光荣,李保生.试论内蒙古萨拉乌苏河沿岸马兰黄土与萨拉乌苏组地层的关系及环境演化.见: 青海柴达木盆地晚新生代地质环境演化,北京: 科学出版社, 1986, 104～121.
(11) 苏志珠,董光荣.内蒙古萨拉乌苏河地区第四纪研究的新进展.干旱区地理, 1994, 17(4): 1～8.
(12) 谢俊义,高尚玉,董光荣等.萨拉乌苏动物群.中国沙漠, 1995,15(4): 1～10.
(13) 李吉均,朱俊杰,康建成等.末次冰期旋回兰州黄土剖面与南极东方站冰岩芯的对比.中国科学 (B辑), 1990, (16): 1086 ～1094.
(14) 刘东生等.黄土与环境.北京: 科学出版社, 1985, 81～99.
(15) 李保生,董光荣,吴正等.我国北方上更新世城川组的建立.地质论评, 1993, 39(2): 91～100. -
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