石油与天然气地质 ›› 2017, Vol. 38 ›› Issue (1): 79-89.doi: 10.11743/ogg20170109

• 油气地质 • 上一篇    下一篇

渤海海域辽西凹陷陡坡带LX构造特稠油藏内部油品品质分布及成因

王冰洁, 徐长贵, 吴奎, 彭靖淞, 刘丰   

  1. 中海石油(中国)有限公司 天津分公司, 天津 300452
  • 收稿日期:2015-06-30 修回日期:2016-12-06 出版日期:2017-02-28 发布日期:2017-02-27
  • 作者简介:王冰洁(1984-),男,工程师,石油地质。E-mail:wangbj6@cnooc.com.cn。
  • 基金资助:

    国家科技重大专项(2011ZX05023-006)。

Quality distribution and origin of super heavy crude in LX Structure of the Liaoxi Sag, Bohai Sea

Wang Bingjie, Xu Changgui, Wu Kui, Peng Jingsong, Liu Feng   

  1. CNOOC Tianjin Company, Tianjin 300452, China
  • Received:2015-06-30 Revised:2016-12-06 Online:2017-02-28 Published:2017-02-27

摘要:

正确认识特稠油藏内部油品品质分布及成因在油藏的勘探评价和开发设计阶段都具有非常重要的意义。基于岩石热解-地震多属性联合的方法建立油品品质判别模型,对渤海海域辽西凹陷陡坡带LX构造新近系明化镇组和馆陶组的块状特稠油藏内部油品品质进行了三维空间刻画,结合流体包裹体资料恢复的古流体活动史和储层物性分析结果,对形成油品品质分布特征的成因进行研究。结果表明:油藏内部油品品质在垂向上明化镇组油层顶部比底部差,馆陶组油层底部比顶部差;平面上在靠近构造高部位相对较差,在断层附近和油藏边界部位油品品质有所变好。整体上油品品质呈现出环带状分布的特征,这种分布特征与原油的“两期成藏和两次稠化”过程关系密切。早期东营组原油经历了成藏第一期和初次稠化过程;晚期东营组经历了初次稠化的油藏遭受破坏在明化镇组和馆陶组再次聚集成藏,并在储层物性越好的层段,由于进一步发生了更强的稠化作用,原油的油品品质也越差。在成藏第二期内,新生成的油品品质较好的原油沿断层和油藏边界充注,导致这些部位的油品品质相对变好,并最终形成现今油品品质空间分布特征。

关键词: 岩石热解, 地震属性, 油品品质, 块状特稠油藏, 辽西凹陷, 渤海海域

Abstract:

A correct understanding of the quality distribution and origin of super heavy crudes is critical to their exploration assessment and development planning.A quality assessment model for characterizing heavy crude samples from the Neogene Minghuazhen and Guantao Formations in the steep slope zone of LX structure in Liaoxi sag of Bohai Sea was established based on a method combining rock pyrolysis with seismic multi-attribute analysis.The quality distribution and origin of the samples was also studied through analyses of paleo fluid activities and physical properties of relevant reservoirs.The result shows that,vertically speaking,the quality of samples from the top is worse than that from the bottom of the Minghuazhen Formation while the Guantao Formation is the opposite with samples from the top better than that from the bottom.Horizontally,the quality of samples from areas near structural highs is less favorable while those near faults and reservoir boundaries yield better-quality samples.As a whole,sample quality shows a zonal distribution,which is considered to be closely linked to the "two-stage reservoiring and densification" of the crude.It is suggested that the crude of the Dongying Formation experienced a reservoiring and densification process in the early stage,and later the reservoirs that had experienced the first densification in the Dongying Fm were destroyed,leading to the re-reservoiring of the crude in the Minghuazhen and Guantao formations.It is also suggested that crude quality is poorer in intervals with better physical properties as a result of more extensive densification.The second stage of reservoiring is proposed to be accompanied by charges of newly-generated better-quality crude along faults and reservoir boundaries that helped improving the quality of existing crude in these areas and resulting in the current spatial distribution of crude quality.

Key words: rock pyrolysis, seismic attribute, oil quality, massive super heavy oil reservoir, Liaoxi Sag, Bohai Sea

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