西南天山南麓切割地貌景观与地质作用

The cutting Landscape and geological process in the southwestern Tianshan

西南天山南麓地区,即新疆克孜勒苏柯尔克孜自治州乌恰县至阿克苏库车县一带近1000Km的范围内,普遍发育由复杂地质作用过程引发的切割地貌。其主要表现为高山、峡谷、深沟等特殊景观,以地形起伏大、切割强烈,多出现悬崖峭壁等为主要特点。西南天山南麓的上述特征性地貌,一方面可以作为旅游景点加以开发,促进地区经济发展;另一方面要密切关注与之相关的泥石流、山洪等地质灾害。这些深大切割地貌景观的形成经历了漫长而复杂的地质作用过程,是地球内生作用和外生作用相结合的产物。西南天山南麓地区,大地构造背景上处于南天山地块与塔里木地块所夹持的过渡带,其中除柯坪地区因中生代隆起未遭受沉积以外,从晚元古代至新生代经历了漫长的海相-河湖相沉积。同时,受新生代以来的印度板块与欧亚板块碰撞作用的远程效应影响,塔里木地块和南天山发生陆内俯冲碰撞,西南天山南麓再次发生阶段性快速隆升,并引发了后期漫长的河流剥蚀,最终塑造了现今西南天山南麓的深大切割地貌景观。

In the southern foothills of the southwestern Tianshan Mountains,within the range of nearly 1000 km from the Wuqia County to the KucheCounty of the Akesu city in the KezilesuKeerkeziAutonomous Prefecture of Xinjiang province,the cutting landforms caused by complex geological processes are generally developed.Its main performances are high mountains,canyons,deep ditch and other special landscapes.The main features are the undulating terrain,strong cutting,and the appearance of cliffs.On the one hand,such characteristic landforms in the southwestern Tianshan Mountains can be developed as typical tourist attractions to promote regional economic development.On the other hand,it is necessary to pay close attention to related geological disasters,such as mudslides,mountain torrents and so on.The formation of these deep and large-cut landscapes had undergone a long and complicated geological process,which was a combination of the endogenous and exogenous effects of the earth.The southern foothills of the southwestern Tianshan Mountains are a transitional zone between the Nantianshan block and the Tarim block on the background of the tectonic setting.Except for the Keping fault,due to the Mesozoic uplift,this area had experienced a long period of marine-lake sedimentation from the Late Proterozoic to the Cenozoic.At the same time,due to the remote effect of the collision between the Indian plate and the Eurasian plate since the new generation,the intracontinental subduction collision occurred in the Tarim block and the Nantianshan block,and the southern foothills of the southwesternTianshan Mountainsonce again experienced a rapid uplifting,which triggeredthe erosion of a river in a long period of time.Eventually it shaped the deep and large cutting landscape inthe southern foothills of the southwesternTianshan Mountains.