川中地区震旦系灯影组储层特征及物性影响因素

Reservoir Features and Physical Influences of the Sinian Dengying Formation(Sinian)in Central Sichuan,China

以钻井资料为基础,采用宏观和微观观测相结合的方法,从岩石学特征、储集空间类型及特征以及物性特征3方面,对川中地区震旦系灯影组储层特征进行研究,同时针对该区碳酸盐岩储层特点,从沉积相、成岩作用和构造作用3方面开展储层物性影响因素分析。研究结果表明,灯影组储层岩石类型主要为白云岩和角砾岩,储集空间主要为次生作用形成的孔、洞和缝,储层类型为低孔低渗的裂缝—孔隙型储层。储层的物性特征受沉积相、成岩作用和构造作用的影响,沉积相是储层形成的基础,物性在滩亚相中最好,并受其分布范围控制。成岩作用则决定了储层的储集性能好坏,其中压实作用、胶结作用、充填作用和硅化作用是破坏孔隙的主要成岩作用;重结晶作用是改善储层物性的重要原因;溶蚀作用储层形成的最关键成岩作用;构造作用形成的裂缝,极大地改善了储层的渗透能力。

The reservoir characteristics of Dengying Formation （Sinian） in central Sichuan Basin were studied from petrology,reservoir space types and characteristics and physical property based on drilling data, macroscopic and microscopic observation. Factors affecting physical properties were also discussed from sedimentary facies, diagenesis and tectonic movement. The rock types are mainly dolomite and breccia, the reservoir spaces are secondary pores, caves and fractures, the reservoir is fracture-pore type with low porosity and low permeability and the beach subfacies have the best physical property. Compaction, cementation, filling and silicification are the destructive diagenesis. Recrystallization and dissolution are beneficial for physical properties. Fractures formed by tectonic movement greatly improve the reservoir permeability.