摘要
乌什西次凹位于塔里木盆地西北缘,隶属于库车坳陷的乌什凹陷。它位于南天山主山脉(哈尔克山)和塔里木盆地柯坪—温宿凸起之间。区域构造格局上,这里是塔里木克拉通向西北自然延伸的部分。次凹北缘的阿合奇断裂是南天山造山带和塔里木克拉通的分界。乌什西次凹内发育与柯坪—温宿凸起相似的晚前寒武纪—古生代地层系统,包括寒武系、奥陶系和石炭系的烃源岩。新近系—第四系碎屑岩建造直接不整合于变形的古生代被动大陆边缘碎屑岩—碳酸盐岩沉积建造之上;剖面上,向南天山方向加厚,向塔里木克拉通方向减薄,呈现典型的前陆盆地剖面结构特征。这是一个晚新生代陆内前陆盆地,叠加在晚海西期—燕山期古隆起之上。这里的构造变形主要有3期,分别是中海西期、晚海西期—印支期和晚喜山期。变形以厚皮冲断构造及其相关褶皱为主,薄皮构造不发育。平面上,主构造线走向NE-SW。剖面上,以南天山向塔里木冲断为主。
The western subsag of Wushi Sag is located in the northwest margin of Tarim Basin and belongs to Kuqa Depression.It is located between the main mountain range of the South Tianshan Mountain(Halke Mountains)and the Kalpin-Wenshu uplift.In terms of regional tectonic framework,it is the natural extension of Tarim Craton to the northwest.The Akqi fault on the northern margin of western subsag of Wushi Sag is the boundary between the southern Tianshan orogenic belt and the Tarim Craton.A Late Precambrian to Paleozoic stratigraphic system similar to that on the Kalpin-Wenshu uplift,including Cambrian,Ordovician and Carboniferous source rocks,is developed in the subsag.Neogene-Quaternary clastic formation directly unconformably overlie the deformed Paleozoic passive continental margin clastic-carbonate formations.In profile,it thickens towards the South Tianshan and thins towards the Tarim Craton,showing a typical profile feature of foreland basin.This is a Late Cenozoic intracontinental foreland basin superimposed on the Late Hercynian to Yanshanian paleo-uplift.There are three major deformation stages,namely Middle Hercynian,Late Hercynian-Indosinian and Late Himalayan or Late Alpine.The deformation is dominated by the thick-skinned structures,while the thin-skinned structure is not developed.On the plane,the main structural line strikes NE-SW.On the profile,the thrusts are mainly from the South Tianshan to the Tarim Basin,forming a basement-involved thrust belt.
作者
王清华
杨威
周慧
缪卫东
Wang Qinghua;Yang Wei;Zhou Hui;Miao Weidong(Research and Development Center of Ultra-Deep Complex Oil and Gas Reservoir Exploration and Development,CNPC,Korla,Xinjiang 841000;Tarim Oil-Field Company,PetroChina,Korla,Xinjiang 841000;Research Institute of Petroleum Exploration&Development,PetroChina,Beijing 100083)
出处
《地质科学》
CAS
CSCD
北大核心
2024年第2期271-287,共17页
Chinese Journal of Geology(Scientia Geologica Sinica)
基金
国家自然科学基金项目(编号:U22B6002)
中国石油天然气股份有限公司前瞻性基础性技术攻关项目(编号:2021DJ0605)资助
关键词
晚前寒武纪—古生代地层系统
被动大陆边缘
二叠纪末—三叠纪冲断和褶皱
晚新生代陆内前陆盆地
基底卷入型构造
乌什西次凹
塔里木盆地西北缘
南天山造山带
Late Precambrian to Paleozoic stratigraphic system
Passive continental margin
End-Permian to Triassic thrust and fold
Late Cenozoic foreland basin
Basement-involved structure
Western subsag of Wushi Sag
Northwest margin of Tarim Basin
South Tianshan orogenic belt
