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中国沙漠 ›› 2008, Vol. 28 ›› Issue (6): 1005-1010.

• 沙漠与沙漠化 • 上一篇    下一篇

关于库姆塔格沙漠“羽毛状”风沙地貌的讨论

董治宝1, 屈建军1, 卢 琦2, 钱广强1   

  1. 1.中国科学院寒区旱区环境与工程研究所, 甘肃 兰州 730000; 2.中国林业科学研究院林业研究所, 北京 100091
  • 收稿日期:2008-03-31 修回日期:2008-05-22 出版日期:2008-11-20 发布日期:2008-11-20

A Discussion on Feathery Aeolian Geomorphology in the Kumtagh Desert

DONG Zhi-bao1, QU Jian-jun1, LU Qi2, QIAN Guang-qiang1   

  1. (1.Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China; 2.Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China)
  • Received:2008-03-31 Revised:2008-05-22 Online:2008-11-20 Published:2008-11-20

摘要: 库姆塔格沙漠是我国最后一个完成综合科考的沙漠,以其北部的“羽毛状”沙丘著称。以往关于库姆塔格沙漠风沙地貌的认识主要基于遥感影像判读。最近深入沙漠腹地的实地考察引发了对该沙漠“羽毛状”沙丘的争论。本文从地质构造、遥感影像纹理特征、沙丘形态特征、风况特征、组成沙丘沉积物的粒度特征、矿物组成、光谱特征、颗粒形貌等多层次、多视角探讨库姆塔格沙漠的“羽毛状”风沙地貌。提出从三种空间尺度上区分“羽翼状”沙漠、“羽毛状”图案(伪羽毛状沙丘)和“羽毛状”沙丘的必要性。认为:①库姆塔格沙漠的 “羽翼状” 总体格局是受新构造运动控制的。②以往基于航片判读确认的“羽毛状”沙丘实际上是由线性(赛夫)沙丘、丘间走廊的亮色浮沙片和残余暗色粗沙地的反照率对比形成的“羽毛状”图案,并非真正的复合沙丘。③真正的“羽毛状”沙丘应该是指有明显新月形沙丘遗留翼角的赛夫沙丘(线性沙丘)的变型。④由赛夫沙丘到“羽毛状”沙丘,风况愈来愈复杂。

关键词: 风沙地貌, “羽毛扇”状沙漠, “羽毛状”图案, “羽毛状”沙丘

Abstract:

Kumtagh Desert is the last desert being broadly scientifically explored in China. The desert is famously characterized by the so-called feathery dunes in the north. The dune types and morphology used to be recognized on remote sensing images until recently. Recent field investigation into the desert led to some arguments on the feathery aeolian geomorphology. This paper attempts to make an overall discussion on the feathery geomorphology based on geological structure, analysis of remote sensing images, dune morphometry, wind regime, sediment size distribution, mineralogy, reflectance spectrum and micromorphology. It is necessary to distinguish between the so-called feathery geomorphology on three spatial scales: feather wing appearance of the desert, feather-like patterns and feathered dunes. The general appearance of feather wing of the desert is controlled by geological structures. The feathery patterns in fact reflect the albedo contrasts between the seif dunes, bright dune-like drifts and the dark inter-dune lag sediments. The wind regime in the area containing the so-called feathery dunes is typical of the regime that produces seif dunes that were considered to be shafts of the feathery dunes, and the vanes of the feathery dunes are in fact bright dune-like drifts with indistinct height from the surroundings rather than true transverse dunes. The feathered dune is a variety of seif dunes. The wind regime becomes more complex from typical linear dunes, to seif dunes and feathered dunes.

Key words: aeolian geomorphology, feather fan appearance, feather-like patterns, feathered dunes

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