克拉通内裂陷边缘台缘丘滩体规模储层发育主控因素与成因模式

四川盆地德阳—安岳克拉通内裂陷边缘发育灯影组四段（灯四段）台缘丘滩体储层，是安岳大气田的主要产层，明确丘滩体储层成因机制是预测优质储层分布、指导勘探部署的关键。综合应用钻井、地震、露头及分析化验等资料，分析灯四段台缘丘滩体规模成储的机制，得到3点新认识：①德阳—安岳克拉通内裂陷东侧边缘发育台缘丘滩储集体，丘滩储集体主要由藻丘和颗粒滩多期复合叠置而成，储层主要储集空间为溶孔、溶洞和裂缝，总体低孔低渗。②储层可分为裂缝—溶蚀孔洞型、溶蚀孔洞型和基质孔隙型等3类，其中裂缝—溶蚀孔洞型储层为优质储层；储层发育主要受台缘丘滩体、准同生期层间岩溶和2期风化壳岩溶作用及多期破裂作用控制；台缘丘滩体储层较好，同一期丘滩体上部储层好、灯四段顶部丘滩体储层好。③台缘丘滩体早期经历的沉积、成储环境基本一致，整体形成特征相似规模储层，在后期构造运动中仍保留大量溶孔和溶洞；喜马拉雅运动导致丘滩体储层现今埋深相差较大，并产生大量裂缝，台缘丘滩体储层仍整体规模发育，勘探前景好。成果对丰富古老深层碳酸盐岩成储理论、指导该领域勘探部署有重要意义。

Main controlling factors and genetic mechanism for the development of high-quality reservoirs in the mound-shoal complexes on the platform margin mound-beach body at platform margin of the inner cratonic rift： Case study of the fourth member of Dengying Formation in the east side of the Deyang-Anyue cratonic rifts， Sichuan Basin

A large platform margin mound-shoal complexes of the fourth member of Dengying Formation（Deng 4 Member） is developed in the margin of Deyang-Anyue intracratonic rift in Sichuan Basin， and the platform margin mound-shoal complexes reservoir in Gaoshiti-Moxi area is the main production layer of Anyue gas field. A clear understanding of the reservoir genetic mechanism of the mound-shoal complexes is the key to predict the distribution of high-quality reservoirs and guide the deployment of exploration. Based on the data of drilling， seismic， outcrop and analytical data， this paper analyzes the reservoir characteristics and genetic mechanism of the mound-shoal complexes at the margin of the Deng 4 Member， and obtains three new understandings： （1） There are two platform margin mound-shoal complexes belts on the margin of Deyang-Anyue intracratonic rift in Sichuan Basin. The mound-shoal complexes are mainly composed of algal mound and granular bank in multiple stages. The reservoir space is mainly dissolved pores， caves and fractures， with low porosity and low permeability in general. （2） The reservoir can be divided into three types， and the fracture-dissolution pore type is the best； the platform margin mound-shoal complexes reservoir is better than the intra-platform mound-shoal complexes， which is the basis for the formation of high quality reservoir； Penecontemporaneous interstratified karst and two-stage weathering crust karst play an important role in the scale reservoir formation of mound-shoal complexes， and the upper part of the reservoir in the same stage is good， and the reservoir at the top of Deng 4 Member is good. （3） Before the Himalayan movement， the reservoir forming and its environments of the two platform margin mound-shoal complexes were basically the same， and the characteristics of the formation of the reservoir were similar. The Himalayan movement led to a great difference in the current buried depth of the reservoir， resulting in a host of fractures and retaining a host of solution pores and caves. The whole platform margin mound-shoal complexes develop large-scale reservoirs and have good exploration prospect. The results enrich the theory of ancient and deep carbonate reservoir forming and its genetic mechanism and provide geological basis for exploration and deployment.