通过对乌夏地区早二叠世风城组油气生储特征研究,认为该区的火山作用不仅能在近火山口相的流纹质弱熔结角砾凝灰岩中,形成以裂缝-气孔为主要组合的油气储集体,而且能使远火山口相白云质凝灰岩和凝灰质白云岩,在有机质丰富的条件下,共同发育为烃原岩；而这种烃源岩由于裂缝系统发育不但构成了源岩型的自生自储的油气藏,而且在横向上还可与同层异相的裂缝-气孔型储层构成自生自储油气藏,形成一套一源两相的生储系统(其中的源、藏共一系统勘探意义重要).应用地化生标、岩石类型和自生矿物等相关资料,对富含火山物质的有机相、火山岩储集类型和储集性能进行了对比和论证.同时,根据大型火山岩油气藏多与近距离的烃源岩关系密切:近源运聚或可自生自储成藏等特点提出:从不同沉积盆地和不同火山机构,总结火山岩油气生储系统分布规律是指导火山岩油气勘探的有利途径.%By studying the feature of source rock and reservoir nature on Fengcheng Formation of the Lower Permian in Wuxia, it is suggested that, owing to the influence of volcanic action, not only the fracture-air hole reservoir can be formed in rhyotaxitic weak alloying rubble tuff near craters, but also higher bearing source rocks, such as dolomitic tuff and tuffaceous dolomite can be generated in crater facies. Because of this kind of source rocks, a petroleum system of two kinds of reservoirs with one source is formed, in which the reservoirs are the self-generating and self-preserving reservoir of mother rock and the horizontal fracture-air hole reservoir (the former is more important). Using the geochemistry index, rock type and authigene, the organic facies' correlation with volcanic construction has been emphatically studied. According to the fact that big volcanic rock reservoirs contacting with source rock in short distance have the feature of near-source reservoirs and of self-generating and self-preserving reservoirs, we propose that the best way to guide the prospect of volcanic rock reservoir is to sum up the distribution regularity of volcanic rock source and reservoir system from different basins and different volcanic rocks and constructions.
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