地质科学2025，Vol.60Issue(4)：953-959,7.DOI:10.12017/dzkx.2025.063
柴达木盆地南八仙背斜上新世—第四纪右旋压扭变形解析及地质意义
Analysis of Pliocene-Quaternary dextral strike-slip deformation of the Nanbaxian anticline in the Qaidam Basin and its geological significance
摘要
Abstract
As a rigid block with a cratonic basement,the study of the internal deformation within the Qaidam Basin holds great significance for understanding the tectonic evolution of the northern margin of the Qinghai-Tibet Plateau.In this paper,the Nanbaxian anticline,located in the northwest corner of the Mahai uplift on the northern margin of the Qaidam Basin and trending east-west,is taken as the research object and analyzed using three-dimensional seismic data.Seismic profiles disclose that the fault systems in different parts possess distinct characteristics,and the coherent horizontal slices reveal that there are four groups of styles in the fault system,namely,axial extension-related normal faults,en-echelon normal faults,detachment thrust faults,and basement dextral compressional-shear faults.The study concludes that the Nanbaxian anticline was formed by the dextral compressional-shear action of the basement fault.In the western region,the detachment surface impedes the upward transmission of the basement strike-slip strain,converting it into detachment folds and the extension along the long axis direction of the folds.In the eastern region,it is a collapsed anticline controlled by the negative flower-shaped dextral strike-slip fault.This study corroborates that the intra-basin deformation in the Qaidam Basin since the Late Miocene has been controlled by dextral shear.关键词
柴达木盆地/马海隆起/南八仙背斜/右旋走滑变形/滑脱褶皱Key words
Qaidam Basin/Mahai uplift/Nanbaxian anticline/Dextral strike-slip deformation/Detachment fold分类
天文与地球科学引用本文复制引用
张关龙,毛黎光,王大华,陈乾威,肖永军,杨帅,刘俊民,陈云锋,张俊锋,王勇..柴达木盆地南八仙背斜上新世—第四纪右旋压扭变形解析及地质意义[J].地质科学,2025,60(4):953-959,7.基金项目
中石化科技攻关项目"柴达木及河西走廊地区油气资源潜力及选区评价"(编号:P22065)资助 （编号:P22065）
