西西伯利亚大型裂谷盆地侏罗系—白垩系成藏组合与有利勘探领域  

Reservoir forming assemblages and favorable exploration fields of Jurassic-Cretaceous in the West Siberian giant rift basin

作　　者：贺正军[1] 温志新[1] 王兆明[1] 阳孝法[1] 刘小兵[1] 梁英波[1] 吉利洋 汪永华[1] HE Zhengjun;WEN Zhixin;WANG Zhaoming;YANG Xiaofa;LIU Xiaobing;LIANG Yingbo;JI Liyang;WANG Yonghua

机构地区：[1]中国石油勘探开发研究院 [2]中国石油集团长城钻探工程有限公司工程服务公司

出　　处：《海相油气地质》2020年第1期70-78,共9页Marine Origin Petroleum Geology

基　　金：国家科技重大专项课题“全球重点领域油气地质富集规律研究”(编号:2016ZX05029-001)资助。

摘　　要：西西伯利亚盆地是一个富含油气的中生代—新生代大型裂谷盆地,盆地的优质烃源岩和储层均发育于侏罗纪—白垩纪裂后拗陷阶段,这与典型裂谷盆地油气富集于裂谷层系的特点具有明显差异。基于系统的岩相古地理编图、成藏要素与成藏组合分析,划分了盆地拗陷阶段的成藏组合,探讨了各成藏组合的油气分布规律,指明了未来需要重点关注的勘探方向。研究表明:侏罗纪—早白垩世巴雷姆期,盆地经历了一次持续时间长、分布范围广的海侵—海退沉积旋回,控制了盆地最主要烃源岩和下部多套成藏组合的发育;早白垩世巴雷姆期末—晚白垩世,转变为短周期、多期次海侵—海退沉积旋回,控制了上部多套成藏组合的发育。侏罗系—白垩系纵向上可以划分为7套成藏组合,已发现的油气主要富集于下白垩统贝里阿斯阶—巴雷姆阶成藏组合和下白垩统阿普特阶上段—上白垩统塞诺曼阶成藏组合。盆地北部陆架阿普特阶上段—塞诺曼阶成藏组合中的波库尔组大型构造圈闭,南部陆上的侏罗系成藏组合中的秋明组与瓦休甘组的岩性圈闭,将是未来最重要的两大有利勘探领域。The West Siberian Basin is a Mesozoic-Cenozoic giant rift basin rich in oil and gas with an area over 238×104 km2.The high-quality source rocks and reservoirs of the basin are developed in the post rift depression stage of Jurassic-Cretaceous,which is obviously different from the characteristics of typical rift basins where oil and gas are concentrated in rift strata.Based on the systematic lithofacies paleogeographic mapping,analysis of elements and assemblages of reservoir forming,this paper divides the reservoir forming assemblages developed in the basin depression stage,discusses the oil and gas distribution law of each reservoir forming assemblages,and points out the exploration direction that needs to be focused on in the future.The results show that the West Siberian Basin goes through a longtime,large-scale transgression-regression sedimentary cycle from the Early Jurassic to the Early Cretaceous Barremian,which controls the development of the major source rock and the lower reservoir forming assemblages within the basin.During the late Barremian to the end of the Late Cretaceous,the basin changes into the short-period and multiple transgression-regression sedimentary cycles,which control the development of the upper reservoir forming assemblages.The Jurassic-Cretaceous can be vertically divided into seven reservoir forming assemblages.Most of the oil and gas are enriched in the reservoir forming assemblages of the Lower Cretaceous Berriasian to Barremian and upper Aptian to the Upper Cretaceous Cenomanian.The large structural traps of the Pourskoye Formation of the upper Aptian to Cenomanian assemblages in the northern shelf and the lithological traps of the Tyumen Formation and Vasyugan Formation of the Upper Jurassic assemblages in the southern land will be the two most important favorable exploration fields in the future.

关 键 词：岩相古地理 成藏组合 油气分布 勘探领域 侏罗纪—白垩纪 西西伯利亚盆地 

分 类 号：TE121.1[石油与天然气工程—油气勘探]