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中国沙漠 ›› 1995, Vol. 15 ›› Issue (3): 201-206.

• 论文 •    下一篇

我国内陆沙漠与海岸沙丘石英颗粒表面结构的对比研究

吴正1,2   

  1. 1. 华南师范大学地理系, 广州 510631;
    2. 中国科学院兰州沙漠研究所, 兰州 730000
  • 收稿日期:1994-12-16 出版日期:1995-09-20 发布日期:1995-09-20
  • 基金资助:
    国家自然科学基金资助项目(49171012)

A COMPARATIVE STUDY OF THE SURFACE TEXTURE OF QUARTZ SAND IN INLAND DESERTS AND THAT IN COASTAL DUNE5,CHINA

Wu Zheng1,2   

  1. Department of Geography, South China Normal University, Guangzhou, 510631
  • Received:1994-12-16 Online:1995-09-20 Published:1995-09-20

摘要: 本文通过扫描电镜分析,对我国内陆沙漠与海岸抄丘石英颗粒表面结构进行了对比研究。研究认为,无论是内陆沙漠砂或海岸沙丘砂,其石英颗粒都具有较好的磨圆度,表面有碟形坑、麻坑及SiO2沉淀物等代表风成环境的典型特征;此外,还叠加有代表原生沙物质来源于水下环境的V型撞击坑、撞击沟等痕迹。然而,受环境尤其是气候影响,其表面结构特征仍有差异,表现在内陆干旱区大陆性气候的沙漠砂的风成机械作用和化学沉淀作用,都要比沿海湿润季风性气候的海岸沙丘砂强烈;但海岸沙丘砂的化学溶蚀作用却比内陆沙漠砂要明显。同属海岸抄丘环境,其石英颗粒表面结构特征表现为北方温带海岸沙丘砂的机械作用痕迹强;而南方热带海岸沙丘砂的化学作用痕迹发育,但机械作用痕迹并非少见,仍然十分明显。

关键词: 内陆沙漠砂, 海岸沙丘砂, 石英颗粒, 表面结构

Abstract: With the analysis of Transmission Eletronic Microscopy(TEM),a comparative study of the surface texture of quartz sand in inland deserts and that in coastal dunes is made in this paper.The study shows that the quartz grains both in inland deserts and in coastal dunes have better roundness,with the characteristic features such as dished pit(D),pockmarked pit(P),and silica(SO2)etc. on the surface,which represent the acolian environment.In addition,these quartz grains still superposed some traces including V-shaped percussion pit(V),percussion furrow and So on,which represent the origin of protosand material.However, because of the environmental affection(Especially,the climate),there are differences between their surface textrures.These differences are as follows:(1)Located ininland arid aera with continental climate,the desert sand underwent stronger aeolian mechanical action and chemical sediment action than the coastal dune sand located in humid area with monsoon climate.But the coastal dune sand has more evident chemical corrosion than the inland desert sand.(2)Even in the same coastal dune environment,for the surface texture of quartz sand,the coastal dune sand in north temperate zone has stronger traces of mechanical action than that in the south tropical zone;yet,the latter has more developed chemical action, and its nechanical traces are noticeable.

Key words: Sand in inland deserts, Coastal dune sand, Quartz surface texture