海洋型冰川塑造地貌特征与铁路选线程式

Landform Characteristics of Marine Glaciers and Railway Route Selection Program

我国将在青藏高原南缘新建一批干线铁路和跨境铁路,必须通过没有建设经验的海洋型冰川区。海洋型冰川具有很强的灾害和塑造地貌效应,目前主要关注其灾害威胁,对冰川地貌的利用研究甚少。首先对海洋型冰川塑造的冰川槽谷、谷肩、冰碛台地以及冰川堵江古堰塞湖盆等地貌的可利用性进行分析;提出海洋型冰川区铁路选线的程式为:首先了解区域冰川的基本情况;然后通过直接作用区和间接作用区的判定,确定铁路可行域;最后通过冰川塑造地貌的专题研究,针对主要备选方案,提出利用冰川地貌优化线路方案的方略。以川藏铁路帕隆藏布流域为例,论述在短直方案中利用冰川槽谷布线、沿主河方案时利用冰碛台地走高线位的措施。

At present,China is about to build a number of trunk railways and cross-border railways on the southern margin of the Qinghai-Tibet Plateau.However,the railways must pass through the marine glacial area and China has no railway construction experiences in these regions.Marine glaciers play a magnificent role in causing disasters and shaping landform.The current researches focus on disaster threats and little has been done on the use of glaciated landform.Firstly,this paper analyzes the utilizability of the four major landforms of U-shaped valley,valley shoulder,moraine terraces and ancient dammed lake basin caused by marine glaciers.Secondly,the program for railway route selection in the maritime glacial area is proposed:first,understanding the basic situation of regional glaciers;then determining the applicable areas of the railway by judging the direct and indirect action areas of glaciers;finally,proposing optimized route selection program based on the thematic study of glacial geomorphology and major alternative plans.With reference to Sichuan-Tibet railway in Palongzangbu Basin,this paper proposes the short and straight route traversing through U-shaped valley,and the main river route following moraine terraces.