松辽盆地南部张强凹陷义县组火山岩储层特征及成藏规律  

Characteristics and hydrocarbon accumulation patterns of volcanic rocks in the Yixin Formation Zhangqiang depression,southern Songliao Basin

作　　者：张斌[1] 

机构地区：[1]中国石油辽河油田分公司勘探开发研究院,辽宁盘锦124010

出　　处：《石油与天然气地质》2013年第4期508-515,共8页Oil & Gas Geology

摘　　要：松辽盆地南部辽河外围探区的义县组广泛发育中-基性火山岩,并在张强凹陷获得了工业油流。依据岩心观察和薄片分析,可将义县组火山岩归纳为14种岩石类型,安山岩类揭示厚度最大、分布范围最广。火山岩主要发育3类岩相7种亚相,喷溢相约占84%。研究区共发育6类主要的原生、次生储集空间类型,4种主要的孔隙组合方式。岩性、岩相和断裂共同控制了储层的平面分带和纵向展布,成岩作用和构造作用决定了储层的储集空间类型、储集性、渗透性和连通性。物性和油藏资料分析表明,火山碎屑熔岩、气孔杏仁状熔岩和火山通道相(火山颈亚相、隐爆角砾岩亚相)、喷溢相上部亚相是最有利的储集岩性、岩相带。在靠近或紧邻生烃洼陷和靠近大断裂的构造高部位,寻找火山口-近火山口相带、以及火山岩喷发旋回的上部和顶部,火山岩油气成藏几率最大。Mafic-intermediate volcanic rocks are widely developed in the Cretaceous Yixian Formation （Kly） in the pe- riphery of Liaohe oilfield in southern Songliao Basin, and commercial oil flow has been tested in these volcanic rocks in Zhangqiang depression. Based on core observation and slice analysis, 14 different rock types have been recognized in the Yixian Fm vocanic rocks. Among them, andesitic lava and andesitic volcanoclastic rocks have the greatest thickness and most extensive distribution. The volcanic lithofacies can be divided into 3 lithofaeies and 7 subfaeies, of which effusive lithofacies accounts for about 84 %. The volcanic reservoirs have 6 main types of primary and secondary reservoir spaces and 4 kinds of pore associations. The plane and vertical distribution of reservoirs are jointly controlled by lithology, litho- facies and faults. The reservoir space types, reservoir capacity, permeability and connectivity are determined by diagenesis and tectonism. According to analyses of physical property and reservoir data, the most favorable reservoir facies belts in- elude the pyroclastic lava, vesicular mandelstone lava, volcanic conduit facies （volcanic neck lithofaeies or concealed ex- plosion breccia lithofacies） and the upper effusive lithofaeies. It is highly possible for the hydrocarbons to accumulate in the vent and proximal vent lithofacies, as well as the upper and top of volcanic eruption cycle/stage in areas adjacent to hydrocarbon kitchen and/or the structural high of deep large faults.

关 键 词：成藏规律 储层特征 岩性-岩相 火山岩 义县组 辽河外围 

分 类 号：TE122.2[石油与天然气工程—油气勘探]