摘要
为了进一步研究源-汇系统模式及相关因素,在双层盐岩结构广泛发育的墨西哥Burgos盆地Perdido构造带,以Wilcox组为研究对象.在有限井控条件下,基于测井、岩心、岩石薄片及三维地震资料,研究了板块活动历史与主要水系分布。通过地宴沉积充填结构、岩屑组成明确物源方向,依据单井相、地震反射与属性特征分析刻画了深水沉积体系特征,综合分析了Wilcox组物源及其控制下的深水扇沉积体系,探讨了源-汇各要素间相关性并建立了耦合模式。研究结果表明,Wilcox组物源主要来自于西侧落基山脉,经Rio Grand.Colorado两大水系搬运至研究区,具有双向物源的特征;主要发育水道化朵叶、近端朵叶和远端朵叶,其中水道化朵叶粒度更粗,储集物性更好,是最为有利的沉积相带;Wilcox组上覆巨厚的盐岩沉积密度较低,其导热率较高可降低地层温度,减缓压实和胶结作用,更有利于盐下储层原生孔隙的保存;充足的沉积物供给量和高效的陆架搬运体系为Perdido构造带深水扇沉积创造了极为有利的条件,源-汇模式表现为落基山脉一Rio Grand.Colorado水系一陆架边缘三角洲一大型峡谷一深水扇模式;由于Perdido构造带勘探程度较低,痊源条件优越,砂体分布广泛,双层盐岩构造为油气成藏创造了诸多有利条件,因此具备广阔的勘探空间与巨大的潜力。
Aiming at Wilcox Formation in the Perdido fold belt of the Burgos Basin,Mexico,where double-layered salt rock structures are widely developed,this study explores the history of plate activity and the distribution of major river systems based on logging,core,thin-section and 3D seismic data under limited well control conditions.The provenance direction was determined by the seismic sedimentary filling structure and debris composition;the characteristics of the deepwater sedimentary system were analyzed based on the single well facies,seismic reflections and attributes.The provenance of the Wilcox Formation and the deep-water fan deposition system under its control were comprehensively analyzed,the correlation between source-to-sink elements was explored and the coupling model was established.The results show that the provenance of Wilcox Formation is mainly from the western Rocky Mountains and is transported to the study area by the two major river systems of Rio Grand and Colorado,characterized by bidirectional provenance.Channelized lobe,proximal lobe and distal lobe are mainly developed in this area.Among them,the channelized lobe is characterized by coarser particles and better reservoir property,and is the most favorable sedimentary facies belt.The overburdened hugely-thick salt rock of Wilcox Formation has low density and high thermal conductivity,and thus can reduce formation temperature,slow down compaction and cementation,which is conducive to the preservation of primary pores in subsalt reservoirs.Extremely favorable conditions for deposition of deep-water fan in the Perdido fold belt are created by abundant sediment supply and an efficient shelf-transportation system.The source-to-sink model is represented by the Rocky Mountains-Rio Grand,Colorado drainage system-shelf edge delta-canyons-deep-water fan mode.In addition to the low degree of exploration,superior source conditions,and extensive sand body distribution in the Perdido fold belt,many favorable conditions are provided by the double-layered salt rock structure for oil and gas accumulation,presenting a broad exploration space and huge potential.
作者
梁建设
黄兴文
蔡文杰
王颖
陈亮
张义娜
Liang Jianshe;Huang Xingwen;Cai Wenjie;Wang Ying;Chen Liang;Zhang Yina(CNOOC International Company Limited,Beijing 100027,China)
出处
《石油学报》
EI
CAS
CSCD
北大核心
2019年第12期1439-1450,共12页
Acta Petrolei Sinica
基金
国家科技重大专项“西非和南美海域重点区油气地质评价及关键技术研究”(2017ZX05032-001)
中海石油(中国)有限公司科技项目“墨西哥海域盐构造与第三系大型储集体及油气成藏”(YXKY-2018-ZY-01)资助