【摘要】 川东北镇巴地区寒武系龙王庙组储层发育相较于川中等地区差异较大。以川东北镇巴地区龙王庙组野外出露剖面为研究对象,利用铸体薄片、扫描电镜、阴极发光、物性分析等方法,分析镇巴地区龙王庙组成岩作用特征。结果表明:镇巴地区龙王庙组储集岩类型为颗粒白云岩、晶粒白云岩、颗粒灰岩和晶粒灰岩。成岩作用类型复杂多样,其中泥晶化作用对储集空间发育起保持性作用;溶蚀作用、早期白云化作用、压溶作用、重结晶作用、破裂作用等起加强性作用;压实作用、充填作用、胶结作用等起破坏性作用。成岩阶段和成岩环境的演化过程为(准)同生成岩阶段的海水潜流环境、早成岩阶段的淡水潜流和渗流环境、中成岩阶段的浅—中埋藏环境和晚成岩阶段的中—深埋藏环境。白云岩为主要的储集岩,粒间溶孔、晶间溶孔和晶间孔为主要的储集空间,总体表现为低孔、低渗的特点,主要受(准)同生期与早成岩阶段白云化作用、溶蚀作用的关键性控制。白云化作用程度低及早期胶结作用发育等因素,造成镇巴地区龙王庙组储集空间发育、物性差于川中等地区的。该结果为川东北地区油气勘探提供参考。更多还原

【Abstract】 Longwangmiao Formation is one of the hot strata for oil and gas exploration in Sichuan Basin.Compared with the central Sichuan Area,the reservoir development of Longwangmiao Formation in Northeast Sichuan is quite different.However,the diagenesis which affects the reservoir quality is less research in this area.Based on the field profile outcrop,casting thin sections,SEM,cathodoluminescence and physical property analysis,the diagenesis is researched.The main rock types are particles limestone,grain limestone,particles dolomite and grain dolomite.The diagenetic types are complex and diverse.Mud crystallization plays a retentive role in the development of reservoir space.Preservation,dissolution,early dolomization,pressure dissolution,re-crystallization and fracture play a constructive role in the development of reservoir space.Compaction,filling and cementation play a destructive role in the development of reservoir space.Besides,the evolution process of diagenetic stage and diagenetic environment is seawater subsurface flow environment in the same diagenetic stage(or quasi-same diagenetic stage),freshwater subsurface flow environment and freshwater seepage environment in early diagenetic stage,shallow to middle buried environment in middle diagenetic stage and middle to deep buried environment in late diagenetic stage.In addition,the main reservoir rock(dolomite)and the main reservoir space(intergranular dissolved pore,intergranular dissolved pore and intergranular pore)are characterized by low porosity and low permeability,which is mainly controlled by dolomization and dissolution in quasi-synonymous and early diagenetic stages.The low degree of dolomization and the development of early cementation caused the development of carbonate reservoir space and poor physical properties of the Longwangmiao Formation in Zhenba Area.更多还原