摘要
基于地质过程,特别是沉积地质过程的理论和方法,利用遥感影像,结合实地测量的地貌与沉积记录、室内沉积分析和测年等资料,研究了玛纳斯河山麓冲积扇的演变过程,探讨了冲积扇演变对区域构造活动的响应。结果表明:(1)晚第四纪以来,玛纳斯河山麓冲积扇从第二排山麓到下游冲积平原,可划分为四期规模较大和三期规模较小的冲积扇,新冲积扇叠置和切割老积扇;(2)天山北麓第二排背斜带霍尔果斯、玛纳斯、吐谷鲁逆断裂-背斜带的间歇式差异升降运动是冲积扇演化的直接动力;(3)冲积扇是构造活动的特征地貌,其演化与山麓断层的构造活动性有明显的相关性。
Based on the geological processes, especially sedimentary geological processes, and the theory of landscape evolution, the authors we made a study of the evolution of alluvial fans at rage-front of Manas River Valley, discussed the tectonic movement at northern piedmont of Tian Mountains by remote sensing images interpretation, field investigating, landform and sediments analyses. It indicates that there have been four periods of larger alluvial fans and three periods of smaller alluvial fans from the foot of the second reverse fault and fold at the north margin of Tian Mountains since the later Quaternary Period. They were named F1, F2, F3, F4, F5, F6, and F7 by the sequence of their formation age. The new alluvial fans＇ formation and evolution have based on the old alluvial fans. According to the phases and traits of tectonic activities,the evolution process of alluvial fans is deducted, which indicate that the evolution of alluvial fans closely relate to the tectonic activities, especially the mode and intensity of motion of the Manas reverse fault-and-fold zone and Tuguru reverse fault-and-fold zone. In addition, according to the spatial contribution of alluvial fans,it is concluded the vertical speed of Manas reverse fault-and-fold zone is lower than that of the Tuguru reverse fault-and-fold zone and the vertical speed of Tuguru reverse fault-and-fold zone become decrease by degrees from east to west, which corroborate that alluvial fans are the characteristic landform denoted the tectonic activities.
出处
《水土保持研究》
CSCD
北大核心
2007年第1期161-163,共3页
Research of Soil and Water Conservation
基金
中科院研究所领域前沿项目(20019002)
国家重大基础研究发展规划项目(TG19943502)成果
关键词
冲积扇演变
构造活动
玛纳斯河
alluvial fans evolution
tectonic activity
Manas River
