中国沙漠 ›› 1993, Vol. 13 ›› Issue (4): 1-5.

• 论文 •    下一篇


赵松龄, 于洪军   

  1. 中国科学院海洋研究所, 青岛
  • 出版日期:1993-12-20 发布日期:1993-12-20
  • 基金资助:

The New Progress in Study of Shelf Sedimentary Environment

Zhao Songling, Yu Hongjun   

  1. Institute of Oceanology, Academia Sinica, Qingdao
  • Online:1993-12-20 Published:1993-12-20

摘要: 运用全球变化的观点,重新认识和探讨第四纪以来、特别是晚更新世以来全球气候变化、中国大陆环境变化对于陆架沉积环境的影响,将是十分必要的。按照这一设想,今后可望在以下三方面获得新进展。1 青藏高原"大冰盖"的形成与长江三角洲沉积的关系:尽管冰川地貌学家对于冰期时期中国大陆环境的特征,特别是古冰川的分布范围、规模等还有不同的意见。无论如何,冰期、间冰期时期长江流域自然环境的变化,有可能会控制长江径流量的变化,影响长江三角洲的发育与成形。2 黄土的亲沙漠性:把黄土与沙漠的分布进行比较,就可以发现两者之间存在密切关系:黄土总是伴随着沙漠而存在;在陆架区,几乎遵照同样的演化规律,在陆架黄土的上风向,总可以找到大范围的沙漠分布区。3 晚更新世末期陆架干旱化、沙漠化的新证据:(1)漫长的风蚀界面;(2)厚层的混杂堆积;(3)典型的休止角结构;(4)统一海相地层的解体;(5)重叠的海底沙丘群;(6)辽阔的残留沉积;(7)海底、近岸和岛屿上的黄土沉积;(8)苏北浅滩的东部砂岩砾石分布区的研究;(9)岩芯中某些干旱化环境特征的研究;(10)陆架上其它风暴沉积的研究。

关键词: 陆架沙漠化, 风成石, 黄土

Abstract: Taking the viewpoint of global changes, the auther tries to find out the influence of global changes and China continental shelf environment changes since Quaternary, especially the Late Pleistocene on the shelf sedimentary environment. According to our assume, the new progress in study of shelf sedimentary environment in future may be in the following fileds: 1. Exploring the relationship between the forming of the great Qinghai-Xizang ice sheet and the Yangtze River delta deposits. Geomorphologists have various views about the characteristis of China continental shelf in glacial epoch, especially about the range and scope of the paleo-glacier, etc. But they have some common understanding about the feature of sedimentary environment in last glacial epoch. For example: the temperate was lower; the scope of glacier was wider; the snowline was lower; the main precipitation was solid state; the runoff of the Yangtze River was much less than today; etc. In any case, the changes of natural envirenments of the Yangtze River valley maybe control the changes of the Yangtze River's runoff and influence the development of the Yangtze River delta. 2. Relations between loess and deserts. Comparing loess with desert distribution, you may find they are closely related. Loess is always accompanied by deserts. In addition, loess of China continent has sth. to do with several main ways of cold wave. Along the route of cold wave, the first appearance is deserts, then the area of loess distribution. In continental shelf region, the same regularity is obeyed. The large range of deserts can be found at the windward side of continental loess. 3. The new evidences of desertization of the shelf deposits in the last stage of the Late Pleistocene. (1) Endless erosion surface. (2) Thick accumilation of mixed deposits. (3) Typical "angle of repose" texture. (4) The disintegration of united marine stratum. (5) Overlapping of submarine dune deposits. (6) A vast expension of relic deposits. (7) Loess deposits in seabed, coast area and islands. (8) Studying of the range of arenaceous shoal in the eastern Shuben Shoal. Recently, many of erosion stones by wind have been discovered by bottom-trawl in the east of the Shubei Shoal. (9) Researching of some features of arid environment in core. (10) Studying of the other windstorm deposits in continental shelf regions.