西天山特克斯达坂晚古生代若干不整合的厘定及地质意义

Clarification of Late Paleozoic Unconformities in the Tekes Daban area of West Tianshan and Its Geological Significance

地层不整合接触是研究地质发展历史及鉴定地壳运动特征和运动时期的重要依据。通过1∶5万区域地质调查,在西天山特克斯达坂一带晚古生代地层中厘定出6个不整合面,证实区内乃至天山地区曾有过至少6幕褶皱运动,丰富了研究区的幕式褶皱内容。新确立了特克斯运动(东图津河组与科古琴山组之间的角度不整合),证实了天山主褶皱幕是鄯善运动,是记录塔里木板块与准噶尔板块碰撞缝合的重要构造运动。特克斯运动等6幕褶皱运动为天山地区构造演化研究提供了更为详尽的幕式演化信息。

The unoonformity between strata makes up an important basis in the study of geological history and the judgment of characteristics and date of crustal movement. On the basis of 1 ： 50 000 geological survey, six uneonformity surfaces were defined in Upper Paleozoic strata of Tekes Daban area within the West Tianshan Mountain. The results obtained not only demonstrate that there have had at least six fold episodes in the study area but also enrich the eontent of fold episode. The newly-established Tekes movement based on the angular uneonformity between Dongtujinhe Forrnstion and Keguqinshan Forrnstion suggests that the Shanshan movement is the main fold episode in the Tianshan Mountains, which has recorded the eollision and suture between the Junggar plate and the Tarim plate. The Tekes movement and the other five fold episodes provide abundant information for the study of tectonics evolution in Tianshan area.