地理科学 ›› 1987, Vol. 7 ›› Issue (4): 306-315.doi: 10.13249/j.cnki.sgs.1987.04.306

• 论文 • 上一篇    下一篇

庐山的地文研究

李吉均, 朱俊杰   

  1. 兰州大学地理系
  • 出版日期:1987-07-20 发布日期:1987-07-20
  • 基金资助:
    国家自然科学基金成果之一

PHYSIOGRAPHIC STUDY OF LUSHAN

Li Jijun, Zhu Junjie   

  1. Department of Geography, Lanzhou University
  • Online:1987-07-20 Published:1987-07-20

摘要: 中国新生代研究曾有两笔重要的理论遗产:一是地文期学说,一是冰期学说。前者强调了地壳运动对地貌发育的影响,杨钟健、巴尔博是这一学派的代表;以李四光为代表的后者强调第四纪的气候变化,着力于寻找古冰川在地形和沉积物中留下的信息。在研究一个地区新生代地质和古地理环境的变迁中,两种观点都是不可或缺的。但是,在具体实践上二者并不总是被恰如其份地对待的。李四光先生虽然认识到庐山是一个断块上升的山体,但由于他把庐山地形、沉积主要归之于冰川成因,对山地上升与地貌发育的关系几乎是略而不提,这样看问题至少是不够全面的[1]。五十年代初期,任美锷首次用侵蚀循环的观点,对庐山地文进行了认真的地貌学研究[2]。近年来,逐渐有较多的学者用现代地貌学的理论和方法对庐山的地貌和第四纪环境演化进行研究,这无疑是走上了能最终解决这个疑难问题的正确途径[3,4,5,6,7]。本文将主要致力于阐明庐山的地文演化,同时也不忽略气候对地貌发育的影响。

Abstract: Three fault cliffs identified clearly on both sides of Lushan show that Lushan experienced three times of intensive block-fault uplifting during Pliocene-Pleistocene period. Consequently, two piedmont trepen with typical features of pediment, now preserved as flat-topped ridges, were formed under subtropic and tropic environment. Deep chemical weathering prevailed at that time and “double surfaces of levelling”s (Budel) developed. In the authors’opinion, it seems that the suggestion of C. R. Twidale which the debris co vered pediment can not develop or at least survive in the humid tropics is unable to be adapted to the case of Lushan completely. Based on the data of paleomagnetic dating collected in recent years, the authors suggest that the Jiujiang gravels were deposited in the early Pleistocene, and the vermiculated red soil with the basal gravels were mostly plinthtic in the middle Plaistocine. Along the banks of the Changjiang River the vermiculated red soil always occurred as continued sidimentary sequence of flood-plain facies, whereas those on the piedment area of Luahan were commonly punctuated by many sedimentary gaps. We have found six sedimentary cyles in the sections of the plinthtic red soil. Among them the lower triplex is dark red in colour with iron pans or honeycomb structure, while the upper triplex is rather pale, has not iron pan and often stained by ferro-manganese coating. Sometimes the upper triplex of the plinthtic red soil constitutes a mantle of low terrace (T2) with a weathered basal gravel underlain beneath. It shows that the upper triplex means not only sedimentary regime but also geomorphologic development of Lushan. After that Hsiashu loess deposited, which can be diveded into two parts. The upper part of Hsiashu loess was surely formed in the main Wurm stage. Evidences obtained in recent years show that there are plenty of morphologic and sedimentary relics created under hot and humid climate and no glacial phenomena had been found in Lushan, area.