大型复杂缓坡带砂体差异富集模式及优质储层预测：以辽中凹陷LD￣A构造为例

Differential enrichment model of sand body and high quality reservoir predictionin in large complex gentle slope zone: a case study of LD-A structure, Liaozhong Sag

惠冠洲 郭涛 蒋恕 加东辉 张如才

中海石油（中国）有限公司天津分公司，天津 300459 中国地质大学（武汉）资源学院，湖北 武汉 430074

储层的发育程度和品质是制约缓坡带勘探的核心问题。文中以辽中凹陷LD￣A构造为例，从钻井、地震、分析化验等资料入手，对目的层沙二层序及体系域开展研究，确定了物源体系、沟谷体系以及沉积区古地貌对沉积体系的控制作用，明确了层序控制源￣汇体系发育特征，断裂￣坡折体系控制砂体平面展布，源￣沟体系控制砂体发育的规模，母岩性质控制沉积砂体的储层物性；建立了砂体富集模式，预测优质储层发育在以变质岩和火山岩为物源区的断阶坡折带断根位置和沉积坡折带之下的辫状河三角洲前缘沉积体内，高效指导了该岩性油气藏的发现和评价。文中研究成果对陆相缓坡带岩性油气勘探具有较好的借鉴意义。

The development degree and quality of reservoir are the core problems restricting exploration of gentle slope zone. Taking LD-A structure in Liaozhong Sag as an example, the sequence and system tract of the second member of Shahejie Formation are studied based on the drilling, seismic and laboratory analysis data.  The controlling effects of provenance system, gully system and paleogeomorphology in sedimentary area  on the sedimentary system are determined. It is clarified that the sequence controls development characteristics of source-sink system, fault-slope break system controls plane distribution of sand bodies, source-gully system controls the size of sand bodies development， and parent rock properties control the reservoir physical property of sedimentary sand bodies. The enrichment of sand body model is established. It is predicted that the high quality reservoir is developed in the foot of faulted slope-break belt with metamorphic rock and volcanic rock as provenance and the braided river delta front deposition body under the depositional slope-break belt, which effectively guides the discovery and evaluation of the lithologic reservoir. The research results in the paper have a good reference for lithologic reservoir exploration in continental gentle slope zone.

10.6056/dkyqt202301012