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中国沙漠 ›› 1994, Vol. 14 ›› Issue (2): 18-24.

• 论文 • 上一篇    下一篇

塔里木盆地大气降尘初步观测研究

刘玉璋1, 董光荣1, 金炯1, 曹悦卿2   

  1. 1. 中国科学院兰州沙漠研究所, 兰州 730000;
    2. 中国科学院贵阳地球化学研究所, 贵阳 550002
  • 收稿日期:1993-09-25 修回日期:1994-06-03 出版日期:1994-09-20 发布日期:1994-09-20
  • 作者简介:刘玉璋,男,1955年生,工程师。1985年毕业于中国科技大学计算机系。主要从事风沙环境与风沙工程实验研究工作,在《科学通报》等学术刊物上发表论文10余篇。
  • 基金资助:
    国家科委"七·五"后期重点课题《塔克拉玛干沙漠综合科学考察》,"第四纪地质与环境"专题组阶段性总结

A PRELIMINARY OBSERVATION AND STUDY OF DUSTFALL IN TARIM BASIN

Liu Yuzhang1, Dong Guangrong1, Jin Jiong1, Cao Yueqing2   

  1. 1. Institute of Desert Research, Academia Sinica, Lanzhou 730000;
    2. Institute of Geochemistry, Scademia sinica, Guiyang 550002
  • Received:1993-09-25 Revised:1994-06-03 Online:1994-09-20 Published:1994-09-20

摘要: 塔里木盆地降尘量分布规律是,塔南明显高于塔北,以昆仑山北麓平原区的民丰至策勒一带为最高,达1127.5t·km-2·a-1(策勒,1990)。以地区划分降尘量大小,其排列顺序依次为:和田地区、喀什地区、巴音郭楞蒙古族自治州、阿克苏地区。大气降尘主要集中在春、夏两季,占全年降尘量的76%,而秋、冬两季仅占24%,降尘量最高月份为7-8月,最低月份为12-1月。比较戈壁与绿洲在同一时间、同一高度和同一风向上的降尘量,绿洲内的降尘量是戈壁地区降尘量的三倍,由此证明,绿洲是大气沙尘的一个主要沉积区。从重矿物组合和粒度分析结果看,大气降尘与塔克拉玛干沙漠砂的背景值以及亚沙土、黄土具有较好的相似性,从而证实塔里木盆地的大气降尘主要来源于盆地内部沙漠砂的微砂和粉砂组分。而分布于昆仑山北坡的亚沙土与黄土正是由塔里木盆地内部地面盛行的西北和东北风吹蚀沙区沉积物,经风力长期搬运分选形成的。

关键词: 塔里木盆地, 大气降尘

Abstract: The precipita tion of dustfall in southern basin was obviously higher than that in north part.The dustfall in the piedmont of Kunlun Mt.was the highest and attained to 1 127.5 t·km-2·a-1(Qira county,1990).Based on the actual observation in April,1990,the dustfall inQira county was 61.52 t·km-2·mon-1.while that in Xiaotang,Luntai county was only 4.12 t·km-2·mon-1.The sequence in the dustfall quantity of district from high to low was Hoton.Kashi,Bayingolin Mongolian Autonomous District and Aksu.The observation during 1989 to 1990 showed that a tmospheric dustfall mainly concentrated in two season of spring and summer,and occupied 76% of annual dustfall,and that of fall and winter occupied 24%,The highest value of dustfall occurred in July to August each year,and the lowest value occurred in December to January,Spatial distribution of dustfall in the basin corresponded with the regional frequen cy(days) of dust storm and strong wind.The consistency became more obvious,espocially in southfringe of the basin.Comparison of dustfall quantity between gobi and oasis at the same time,height and wind direction suggests,that the dustfall in oasis is nearly 3 times higher than that in gobi,which showed that oasis might be a main dustfall place.It is re ported that the sub-sandy loess and loess on north slope of Kunlun Mt.and Altun Mt.were aeolian,which might be related to the dustfall there,The analysis of hcavy mineral assemblage and the particle-size of dust showed that the dustfall was well similar to the background value of Taklimakan Desert and that of sub-sandy loess and loess,It is concluded that the atmospheric dustfall in the basin mainly came from the very-fine sand and coarse silt of dune field.Therefore,the sub-sandy loess and loess on north slope of Kunlun Mt.and Altun Mt.were wind-eroded deposits transported by northwest wind and northeast wind from the in terior of the basin.

Key words: Tarim Basin, Atmospheric dustfall