论文部分内容阅读
一 区域概述 成都平原位四川盆地西北部,海拔五百至七百公尺,面积约五千方公里,人口约五百万,在政治区划上跨有一市二十县。 平原之西邻为藏边山地,与西藏大高原相连,海拔在三千公尺以上。平原之东缘为龙泉山脉,系突峙盆地中之山岭,海拔约一千公尺。两者之间,为一洼地。源自藏边山地诸河,自山区骤入洼地,所挟泥沙,委弃沉积,初为各自独立之冲积扇,日积月累,群扇相连,乃成为今日广大之山麓冲积平原。
A regional overview Chengdu plain in the northwestern Sichuan Basin, elevation 500 to 700 meters, an area of about 5000 square kilometers, a population of about five million, in the political divisions across a city twenty counties. The west part of the plains is a Tibetan mountainous area, connected to the Tibet Plateau at an altitude of over 3,000 meters. The eastern edge of the plain is the Longquan Mountains, which is a mountain in the Chongzhi Basin at an elevation of about 1,000 meters. Between the two is a depression. Originated from rivers and lakes in the possession of mountains and rivers, they plunge into the depressions from the mountainous areas and sediment is entrapped. Sediments are initially abandoned as alluvial fans that are independent from each other. Over time, they are connected by groups of fans, becoming the alluvial plain in the foothills of today.