地理学报 ›› 1984, Vol. 39 ›› Issue (1): 86-96.doi: 10.11821/xb198401010

• 论文 • 上一篇    下一篇

北京地区长辛店砾石层的沉积学特征与西山地貌发育的几个问题

李容全, 刘增森   

  1. 北京师范大学地理系
  • 出版日期:1984-01-15 发布日期:1984-01-15

SOME PROBLEMS ABOUT THE RELATIONSHIP BETWEENTHE SEDIMENTOLOGICAL TRAIT OF CHANGXINDIANFORMATION AND THE GEOMORPHOLOGICAL DEVE-LOPMENT OF XISHAN MOUNTAIN, BEIJING

Li Rong-quan, Liu Zeng-sen   

  1. Dept. of Geography, Beijing Normal University
  • Online:1984-01-15 Published:1984-01-15

摘要: 在北京西南郊的长辛店附近出露着长辛店组砾岩。根据砾岩中产出的鱼鳖类未定种化石残体以及砾岩的岩性与产状等特征,周明镇先生断定:“砾石层的时代应为第三纪初,最新不能晚于渐新世后期”。1977年,翟人杰同志根据最新发掘出的四个种的哺乳动物化石,讨论了长辛店组沉积的时代。他认为该层属于早第三纪晚始新世。可见,长辛店组砾岩是北京平原边缘出露的最古的新生代地层。

关键词: 长辛店组, 北京西山, 沉积学特征, 地貌发育, 喷出岩, 砾石层, 砾岩, 地形倒置, 始新世, 岩性组成

Abstract: The Changxindian formation which outcrops on the Southwestern Beijing suburb is the deposits of Early Cenzoic. The statistics of the rock composition of Changxindian formation indicated that Jurassic extrusive rocks takes the predominant part in the lithologic composition while materials from the Sinian Sub-group come next, the intrusive rock components are insignificant.Basing on its special lithological composition and the features of geologic structure of the source area, the authors try to reconstruct the evolution of the landforms of the Xishan (West Mountain region).1. During the deposition of Changxindian formation the folded topography of Yan-shan period in Xishan Mountain region was peneplaned, then it was uplifted in the Himalayan movement, consequently, an inversion of relief has occurred.2. Guangting Gorge of Yongding River has been formed after Eocene.3.Dashi River and Guangting Gorge belonged to two different drainage systems in Eocene, the development of karst around the Dashi River region appeared earlier than that of the Guangting Gorge region.