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中国沙漠 ›› 1998, Vol. 18 ›› Issue (2): 111-117.

• 研究论文 • 上一篇    下一篇

腾格里沙漠东南缘沙漠演化的初步研究

阎满存1,2, 董光荣1, 李保生3, 李华梅2, 杨龙江4   

  1. 1. 中国科学院兰州沙漠研究所 兰州 730000;
    2. 中国科学院广州地球化学研究所 广州 510640;
    3. 华南师范大学地理系 广州 510631;
    4. 广东省华南工程物探技术开发总公司 广州 510080
  • 收稿日期:1997-04-28 修回日期:1997-10-06 出版日期:1998-06-20 发布日期:1998-06-20
  • 作者简介:阎满存,男,1962年生,博士生,助理研究员。主要从事地貌、第四纪地质和地球化学方面的研究工作。
  • 基金资助:
    中国科学院重大项目(K Z951-B1-206, KZ951-A1-402)

A PRELM INARY STUDY ON THE EVOLUTION OF SOUIHEASTERNMARGJN IN TENGGERDESERT

YAN Man-cun1,2, DONG Guang-rong1, LI Bao-sheng3, LI Hua-mei2, YANG Long-jiang4   

  1. 1. Institute of Desert Research, Chinese Academy of Sciences, Lanzhou 730000;
    2. Institute of G eochem istry, Chinese A cademy of Sciences, Guangzhou 510640;
    3. Institute of G eochem istry, Chinese A cademy of Sciences, Guangzhou 510640;
    4. South China Company for Geophy sical Exp loration, Guangzhou 510080
  • Received:1997-04-28 Revised:1997-10-06 Online:1998-06-20 Published:1998-06-20

摘要: 根据不同地貌单元地层沉积相组合、典型剖面热释光和14C测年以及粒度、孢粉和化学元素等资料分析,重建了腾格里沙漠东南缘沙漠演化的过程。进而讨论了沙漠演化与冰期气候波动和东亚季风环流盛衰变化的耦合关系。

关键词: 腾格里沙漠, 地层沉积相, 沙漠演化模式, 古季风

Abstract: Since the Quaternaiy the southeastern maigin of the Tengger Desert have exist-ed three large geomo rphologic unites- Yellow River valley, piedmont plateau and eolian-sand plaii. The Quaternary strata sedmentary facies changed at varying geomo rphologic units During the early Pleistocene the Yellow River valley deposited by flivial pebble and silty sand and the piedmont plateau with gravels. During them iddle Pleistocene eolian-sand occurred in the highest terrace of Yellow River and the eolian sand is dated to 33043±58134 aB. P. byTL, h which calcareous crust and sandy paleosols can be seen; further results of element analysis for this eolian sand profile show that the content of CaCO3 in calcareous crusts are up to 30.73%~47.32%, and the content of Ca Mg Sr/Ba Co V,Cr Ni are ralatively hgh while in paleo-sand layer the content of CaCO3 is only 1%~2% andw ith a higher content of K, Na, Al Fe Mn, Tietc. During the lateP leistocene piedmont plateau was consisted of alternating accumulation of gravel, eolian-sand and sandy loess or eolian sand and lancastrine facies and eolian sand continued accumulating in the eolian plain and the higher terrace of Yellow River pollen analysis for paleo-sand profile demonstrated the plant cover during sandy loess accumulation was arid and semi-arid steppe dominated by Chencpod iaceae Artemisia, Grem ineae, Ephedre etc. During the Holocene eolian plaii and Yellow River valley is characterized by the alternating of ancient eolian sand, sandy loess and sandy paleosols or calcareous plant-rootsi It can be seen that, since middle Pleistocene the southeastern m argin of Tengger Desert has undergone a series of normal and reverse alternating from the occurrence of shifting sand to the spread or fixation, semi-fixation and reduction of the desert to grassland asw ellasw eakly pedogenic processes Simultaneously, the bioclm atic zones in the area also underw ent alternating from dry, co ld and windy desert desert steppe to semi-arid steppe semi-arid or semi-humid sparsely wooded steppe The evolition processes is controlled by the coupliig between the glacial and in terg lacial clmate fluctuations and the prosperity and decline of eastern Asian monsoon.

Key words: Tengger Desert, Sedin entary facies, Desert evolution model, Palaeom onsoon

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