焉耆盆地博湖坳陷三工河组层序格架及沉积体系的时空配置关系

Temporal and Spatial Configuration of Sedimentary Systems and Sequence Stratigraphic Framework of Sangonghe Formation in Bohu Depression of Yanqi Basin

利用层序地层学、沉积学原理和方法,对博湖坳陷下侏罗统三工河组进行了层序划分和沉积体系时空配置关系的研究。建立了三工河组的层序地层格架,将其划分为J1s3、J1s2和J1s13个三级层序,其层序和体系域的变化主要受控于凹陷内沉降中心的分布,沉积主要受控于盆地边缘的南缘陡坡带、北缘缓坡带。每个三级层序低水位体系域发育局限,湖扩与高水位体系域发育。沉积体系构成以扇三角洲、湖泊和辫状河三角洲为主。在建立沉积体系时空配置关系的基础上探讨了沉积体系的演化。

The sequence-stratigraphic framework of Sangonghe Formation （Jurassic） in Bohu depression of Yanqi Basin is established based on the principles of sequence stratigraphy and sedimentolgy and the study of the temporal and spatial configuration of sedimentary systems. The Sangonghe Formation, classified into three third-order sequences, has its sequence and system tracts controlled by distribution of the subsidence centers. While the deposition is mainly subject to the south steep slope belt and the north gentle slope belt of the boundary of the basin. Each LST is limitedly developed, but the EST and HST are well-developed. The depositional systems in this area are dominated by fan delta, lacustrine and braided delta respectively. The evolution of the depositional systems is also studied on the basis of building the temporal and spatial relation.