东营凹陷青坨子凸起馆陶组沉积相演化特征及相模式

Features of Depositional Facies Evolution and Depositional Model of Guantao Group in Qingtuozi Heave

随着现有勘探区块不断投入开发,青坨子凸起西坡和南坡馆陶组作为勘探程度很低的潜在目标日益受到重视。综合利用地震、测井、录井、分析化验资料及前人研究成果,运用层序地层学方法和技术,对工区馆陶组地层的分布、构造特征以及沉积环境进行了研究。馆陶组沉积时期研究区广泛发育河流,物源来自凸起东北部。沉积早期河道广布,砂体发育、连片性较好,晚期整个河流沉积体系向物源区后移、泥质盖层发育。在构造高位,河流主要沿断层倾向方向流动;在构造低位,河流走向受断层走向控制。靠近凸起的凹槽部位,受同生断层作用发育河道沉积,凸起外侧的构造高点发育泛滥平原沉积。

With the growth of exploitation of available exploration targets in Dongxin Oilfield, Guantao group in the west and south part of Qingtuozi heave, was considered to be more and more important as the potential and favorable prospecting target with low exploration degree. With the combination of seismic, logging, testing data and research of predeccors, and by using sequence stratigraphy, strata distribution, structure characteristics and depositional environment of the workarea were studied. Massive fluvial facies was developed in the workarea during Guantao sedimentation, and the source was from northeast of the heave. Widespread channels with abundant sand body were deposited in the early time; and the whole fluvial system was moved back to source area in the later time, with shale cap developed. The river flows along the direction of fault dip in high structure position, and its strike at low structure position is controlled by fault strike. Fluvial channel is developed at groove near the heave, which is controlled by synsedimentary faults; flood plain is deposited at the structure highs outside the heave.