松辽盆地月亮泡地区岩性油藏成藏规律研究

STUDY ON THE LITHOLOGIC RESERVOIR ACCUMULATION RULES OF YUELIANGPAOAREA IN SONGLIAO BASIN

通过对研究区各成藏组合沉积微相的研究及典型油藏剖面的解剖,分析了在西部英台—白城沉积体系控制下的月亮泡地区垂向上不同含油气组合岩性油藏的成藏主控因素、成藏规律及相应的勘探思路,丰富和完善了松辽盆地斜坡区岩性油藏的研究。研究表明:三角洲前缘相变所造成的岩性变化是上白垩统姚二+三段成藏的主要控制因素,嫩江组区域性水进形成的稳定泥岩为姚二+三段的成藏提供了良好的区域盖层,一定厚度的直接盖层是姚一段、青山口组及泉四段成藏的主要控制因素,而三角洲前缘相带良好的储盖组合及沉积微相相变造成的砂体侧向尖灭是这3套油层发育岩性油藏的又一重要原因;青山口组大套泥岩中发育的超压为形成"源下成藏"的泉四段提供了油源及排烃动力条件。

Based on the study of the sedimentary microfacies and typical reservoir sections of Yueliangpao areacontrolled by western Yingtai-Baicheng depositional system,the main controlling factors,accumulation rules andcorresponding exploration strategies for all plays was analyzed in this paper,which enriched and consummatedthe lithologic reservoir research of the slope area of Songliao Basin.The study showed that lithology changes intransverse caused by sedimentary microfacies change of delta front mainly controlled the 2nd and 3rd Menebersof Yaojia Formation,the upper Cretaceous' accumulation,and the stable mudstone deposited in the process offlooding of Nenjiang stage provided a good regional seal for the 2nd and 3rd Menebers of Yaojia Formation.Acertain thickness direct caprock is the main controlling factor for the 1st Member of Yaojia Formation,QingshankouNo.5 Abstract IIIFormation and the 4th Member of Quantou Formation' accumulation.And the good reservoir-caprock assemblageand sandbody pinch-out under the influence of microfacies changes of delta front also played an important rolein lithologic reservoir forming.Moreover,the overpressure developed in the massive mudstone of QingshankouFormation.It provided oil source and expulsion driving force for the 4th Member of Quantou Formation.