苏里格地区马五_5亚段储集层特征及其主控因素

Study on Reservoir Characteristics and Main Controlling Factors of Ma-5_5 Submember in Sulige Area

基于岩心观察、镜下薄片、扫描电镜、压汞以及物性等资料,结合地球物理、地球化学技术方法,对苏里格地区奥陶系马家沟组马五5亚段储集层特征进行了系统的研究,分析了影响储集层形成和发育的主要控制因素,预测了有利储集层的分布范围。马五5亚段储集层主要岩性为泥—粉晶白云岩和粉晶白云岩;主要储集空间类型为晶间孔、晶间溶孔;马五25小层的物性较之马五15小层更好。沉积相是储集层形成的物质基础,云坪微相是储集层发育的有利沉积相带;成岩作用是形成有利储集空间的重要保证,白云岩化、溶蚀作用等为建设性成岩作用;构造作用是储集层发育的有效补充因素。

Based on core observation and the analysis on the data of thin section, SEM, mercury injection and petrophysical property andusing geophysical and geochemical methods, the paper systematically studies the reservoir characteristics of Ma-55 submember of Ordovi-cian Majiagou formation in Sulige area, analyzes the main controlling factors influencing reservoir formation and development and predictsthe distribution of favorable reservoirs. The reservoir of Ma-55 submember is dominated by argillaceous-silty dolomite and silty dolomitewith the main reservoir spaces of intercrystalline pores and intercrystalline dissolved pores. The petrophysical properties of Ma-525 are betterthan those of Ma-515. Sedimentary facies is the material basis for reservoir formation and the microfacies of dolomite flat is the favorable sedi-mentary facies belt for reservoir development. Diagenesis is a significant guarantee to form favorable reservoir spaces and the constructivediagenesis such as dolomitization and dissolution are favorable to reservoir reconstruction. The tectonism is the effective supplement for res-ervoir development.