下刚果盆地下白垩统Albian阶碳酸盐台地地震沉积学

在构造-沉积模式理论指导下,综合利用钻井岩心、测井和三维地震资料,探讨下刚果盆地下白垩统Albian阶碳酸盐岩沉积体系的地震沉积学特征及有利储层发育相带的空间展布和演化规律,为有利区块预测和勘探目标优选提供地质依据。结果表明:下刚果盆地A区块及邻区Albian阶可归纳出3种混积相和6种亚相及更多的微相类型;在建立混积相沉积模式的基础上,确定了滩体生长期次、方向和古地貌高,明确了A区块及邻区块重点层段滩体发育演化规律,精细恢复了SQ2和SQ3层序沉积演化史,识别出各层序内部演化特征和有利储层发育相带分布规律。提出了井震一体化多尺度融合研究思路,系统建立了下刚果盆地Albian阶三维沉积动态演化模式,论证了"台沟控带、台缘控滩、滩控储层"的优势相带和储层发育机理。

Study on seismic sedimentology of the Lower Cretaceous Albian Stage carbonate platform in the Lower Congo Basin

Data of drilling cores,logging and three dimensional seismic data are used to discuss the characteristics of seismic geology,spatial distribution of favorable reservoir and evolution regularity of the carbonate sedimentary system in Lower Cretaceous Albian Stage in Lower Congo Basin,so as to provide geological evidence for the prediction and selection of exploration targets.It shows that the Block A and its adjacent area in Albian Stage,Lower Congo Basin can be classified into 3 kinds of hybrid facies,6 kinds of subfacies and even more kinds of microfacies.On the basis of establishment of sedimentary model of hybrid facies,the growth period,direction and paleotopography height of beach body are determined,the development and evolution rules of the beach body in the key section of Block A and adjacent area are clarified,the sedimentary evolution history of SQ2 and SQ3 sequence is finely reconstructed and the evolution characteristics of each sequence and the distribution rules of favorable reservoir facies belt are recognized.Accordingly,a research system of comprehensive multi scale combination is proposed and the 3D dynamic sedimentary evolution model of Albian Stage in the Lower Congo Basin is established.It reveals that the platform gully controls the belt,platform margin controls the beach and beach controls reservoir is the reservoir development mechanism in the area.