【摘要】 潍北凹陷是郯庐断裂带内部典型的走滑拉分盆地,火山岩发育在古近系孔三段。通过对该区火山岩油气藏成藏要素研究,认为孔二中上亚段油页岩和灰质泥岩为主力烃源岩;遭受强烈风化作用的溢流旋回上部亚相为主要储集层,储集空间以裂缝—孔隙型为主;断距较大的反向断块与两套主力烃源岩直接对接,形成良好的圈源配置;断层和风化壳形成的输导网络提供了有利的运移条件;孔二中下亚段暗色泥岩提供了良好的盖层条件。根据潍北凹陷孔三段火山岩油气藏成藏特征,总结出3种成藏模式,即北部洼陷带近源相控成藏模式、灶户断鼻带断鼻带中源断—相双控成藏模式和南部斜坡带远源断控成藏模式,灶户断鼻带和南部斜坡带是有利成藏区。更多还原

【Abstract】 Weibei sag is a typical strike-slip pull-apart basin in Tanlu fault zone.The volcanic rocks mainly distributed at Ek~3 of Eogene.Based on the analysis of the reservoir-forming factors of volcanic reservoirs in this area,oil shale and lime mudstone of middle-upper submember of Ek~2were considered to be the chief source rocks.The upper overflow subfacies subjected intense weathering were the main reservoir,and fractured-pore was the main reservoir space.Reverse fault blocks with greater displacement exposed directly to two groups of source rocks and formed a favorable trapsource configuration.Grooming network formed by fault and weathering crust provided favorable migration conditions.Dark mudstone of middle-lower submember of Ek~2 provided a favorable cap rock condition.Three kinds of accumulation modes were summarized:Near-source lithofacies controlled accumulation model in northern subsag belt,middle-source fault-lithofacies controlled accumulation model in Zaohu fault zone and farsource faults controlled accumulation model in southern slope zone.Zaohu fault zone and southern slope zone were favorable area of hydrocarbon accumulation.更多还原