川中地区龙王庙组优质储层发育的主控因素及成因机制

基于钻井、地震和测井等资料，研究川中地区下寒武统龙王庙组储层特征，分析优质储层发育的主控因素，建立优质储层发育模式。结果表明：①川中地区龙王庙组优质储层主要发育于局限台地相的台内颗粒滩中，以厚层块状颗粒白云岩为主；②储层主要的储集空间为溶孔、溶洞和裂缝，并根据储集空间的不同，可将储层划分为裂缝-溶蚀孔洞型、裂缝-溶蚀孔隙型和裂缝-晶间孔型3类，其中裂缝-溶蚀孔洞型储层质量好，为优质储层；③高石梯-磨溪古隆起控制了颗粒滩沉积，层间岩溶作用和准同生白云石化作用是优质储层发育的基础，而古隆起与颗粒滩、多期溶蚀作用和裂缝等因素的有效配置可形成优质储层；④古隆起核部的颗粒滩储层发育较好，古隆起上相对古地貌高处的颗粒滩储层较好，单个颗粒滩的核部储层较好。

Main controlling factors and genetic mechanism for the development of high-quality reservoirs in Longwangmiao Formation,central Sichuan Basin

Based on drilling, seismic, and logging data, this paper studies the reservoir characteristics of the Lower Cambrian Longwangmiao Formation in central Sichuan Basin, analyzes the main controlling factors for the development of high-quality reservoirs, and establishes the development model of high-quality reservoirs. The results show as follows. (1)The high-quality reservoirs of Longwangmiao Formation in central Sichuan Basin are mainly developed in the intraplatform grain beaches of limited platform facies, dominated by thick-layered massive grain dolostones. (2)The main reservoir spaces are dissolution pores, karst caves and fractures. According to the types of reservoir spaces, the reservoirs can be divided into fracture-dissolution cave type, fracture-dissolution pore type and fracture-intergranular pore type, of which the fracture-dissolution cave type is of good and high quality reservoir. (3)The Gaoshiti-Moxi paleohigh controls the deposition of grain beaches. Interlayer karstification and penecontemporaneous dolomitization provide a basis for the development of high-quality reservoirs. The effective allocation of paleohigh, grain beach, multi-period dissolution and fractures form high-quality reservoirs. (4)The grain beach reservoirs are well developed in the core of paleohigh. The grain beach reservoirs are better at the higher paleogeomorphologic position of paleohigh and the core of single grain beach.