摘要
位于青藏高原和华北板块两大构造带交汇处的河西走廊带中西段酒东盆地,早白垩世为典型断陷盆地,但对其断陷形成机制存在明显争议。因早白垩世两大构造带的主体构造作用明显差异:北—南向挤压和北西—南东向伸展,为深入了解哪一种作用是控制早白垩世酒东盆地形成的主要因素,本研究特选取远离新生代强烈活动的阿尔金断裂带,在河西走廊带中西段的酒东盆地中,对程度较高的营尔凹陷进行了二维地震解析、沉积中心转换、沉积重矿物ZTR指数差异性的综合研究,表明早白垩世酒东盆地营尔凹陷是在侏罗纪的断陷盆地基础上继承而来,主要受到来自南部青藏高原北—南向挤压作用,重新激活了前期的构造正断层,进而形成新一期断陷盆地,其断陷演化可分为初始断陷、强烈断陷和断陷萎缩3个阶段。
The Jiudong Basin, situated in the triangular belt between the Tibetan Plateau(TP) and the North China Plate(NCP) ,is one classical rift basin,but there is controversy for the mechanism of rifting during the Early Cretaceous. Because there are obvious differences for the tectonic forces between the two tectonic belts:N-S compressive stress of TP and NW-SE extension of NCP, it is so different to truly understand which tectonic force the formation of the Jiudong Basin was controlled in during the Early Cretaceous. So this study chooses the Yinger depression of the Jiudong Basin,which is far away strong tectonic Ahyn Tagh Fault (ATF) and has been studied by more geologists, to analysis the process of rifting formation using multiple methods, including mapping and correlation of 2D seismic reflection data, transition of sedimentary center,and ZTR values of sedimentary heavy minerals. All data indicate that rifting of the Yinger depression began to be active because the Jurassic normal faults were active due to the N-S extrusion of TP, the Early Cretaceous. And the formation process is divided into three stages : Initial, strong, atrophy rifting.
出处
《地质科学》
CAS
CSCD
北大核心
2011年第3期826-837,共12页
Chinese Journal of Geology(Scientia Geologica Sinica)
基金
The 111 Project of China Grant(编号:Project B07011)
教育部新教师基金(编号:20105122120013)
四川省教育厅重点项目(编号:09ZA005)资助
关键词
酒东盆地
营尔凹陷
早白垩世
断陷盆地
正断层
Jiudong Basin,The Yinger depression,The Early Cretaceous,Rifting basin, Normal fault
作者简介
冉波,男,1980年9月生,博士,讲师,岩石学专业。E-mail:rabo1980@163.com