摘要
在TM遥感图像解译和地形图分析的基础上,结合野外观察,研究了川西岷江上游深切河谷地形地貌特征,认为岷江河谷晚新生代的下切历史分为2个阶段.早期下切作用主要发生在新近纪时期,下切深度大于2 000m,平均下切速率为770m/Ma;晚期下切作用发生在中、晚更新世时期(0.8Ma以来),沿岷江上游形成典型的'V'型谷地,河谷平均下切速率南段为1 875m/Ma,中段为1 620m/Ma,北段为375～750m/Ma.岷江深切河谷地貌的形成是对川西高原新近纪-第四纪快速隆升的响应,为高原隆升历史的恢复提供了重要的地貌证据.
Based on the Landsat TM imagery interpretation and topographic analysis and coupled with field observations, this paper describes the morpho-structural and topographic characteristics of the deep-incised river valleys along the Minjiang upstream and proposes a 2-stage evolution model of the valley incision processes. It points out that the early incision stage occurred during the Neogene. In this period, the Minjiang upstream incised into a depth of at least 2000 m. The incision rate averaged 770 m/Ma. The late incision stage resumed since the Middle Pleistocene （around 0.8 Ma）, and the typical“V” shaped valleys were materialized on the Minjiang upstream. The mean incision rate during this stage was about 1875 m/Ma along the southern segment, about 1620 m/Ma along the middle segment and 375-750 m/Ma along the northern segment. The form of deep-incised morpho-structural features of the Minjiang upstream was in response to the rapid uplift of the West Sichuan Plateau during the Neogene-Quaternary, and provides morphological evidences for the episodic uplift.
出处
《成都理工大学学报（自然科学版）》
CAS
CSCD
北大核心
2005年第4期331-339,共9页
Journal of Chengdu University of Technology: Science & Technology Edition
基金
国土资源部"十五"重点基础研究项目(20010202)
关键词
岷江上游
深切河谷
下切速率
高原隆升
晚新生代
Minjiang upstream
deep-incised valley
incision rate
plateau uplift
Late Cenozoic
