准噶尔盆地克百断裂带石炭系内幕型火山岩储层特征及成藏规律

Characteristic and accumulation patterns of Carboniferous inside-type volcanic reservoir in Kebai Fault Zone of Junggar Basin

基于测井、实验、试油等资料,根据生油岩、储盖组合、输导体系、圈闭等油藏关键要素的配置,分析准噶尔盆地克百断裂带石炭系内幕型火山岩储层特征及油气成藏规律。结果表明:研究区石炭系内幕型火山岩储层发育于石炭系顶界800 m以下,内幕储层有利岩性主要为凝灰岩和安山岩,储集空间主要为裂缝型和裂缝—孔隙型;火山爆发间歇期沉降的粉砂质凝灰岩为良好的盖层,输导体系为克百断裂及次生断裂,在逆冲推覆构造作用下,形成的构造—岩性圈闭为油气提供良好的富集条件。克百断裂带石炭系内幕型火山岩于玛湖凹陷二叠系烃源岩生成油气,沿油源断裂运移,在火山岩内幕构造—岩性圈闭聚集成藏,形成新生古储的近源成藏模式。该结果为准噶尔盆地克百断裂带石炭系深层内幕型油藏勘探提供指导。

Based on the data of logging,experiment and oil test,and according to the allocation of key reservoir elements such as source rock,reservoir cap combination,transport system and trap,we have summarized the characteristics of insider volcanic reservoir and revealed the reservoir forming law of Carboniferous insider volcanic reservoir.The results indicate that the inner volcanic reservoir in the study area is 800 m away from the top of Carboniferous System.The favorable lithology of the inner reservoir is mainly tuff and andesitic basalt.The favorable combination of reservoir space is fracture type and fracture pore type.The silty tuff deposited during the intermittent period of volcanic eruption is a good gap.The transport system is Kebai Fault and secondary fault.Structural lithologic traps formed under thrust nappe structure provide good enrichment conditions for oil and gas.The reservoir forming law of Carboniferous internal volcanic rock reservoir in Kebai Fault Zone was the oil and gas generated by Permian source rock in Mahu Sag migrated along the oil source fault,accumulated in the inner structural lithologic trap of volcanic rock,and formed the near source reservoir forming model of Cenozoic ancient reservoir.The results provided guidance for the exploration of Carboniferous deep insider reservoir in Kebai Fault Zone in Junggar Basin.