裂谷与被动陆缘叠合盆地的盐构造与油气成藏——以西非下刚果-刚果扇盆地和宽扎盆地为例

孙自明; 何治亮

doi:10.11781/sysydz201603287

裂谷与被动陆缘叠合盆地的盐构造与油气成藏——以西非下刚果-刚果扇盆地和宽扎盆地为例

doi: 10.11781/sysydz201603287

中国石化石油勘探开发研究院, 北京 100083

基金项目: 中国石化科技项目"安哥拉深水区块勘探潜力与目标评价技术研究"(P11061)资助。

详细信息

作者简介:
孙自明(1964-),男,博士,高级工程师,从事油气勘探和盆地构造分析研究。E-mail:sunzm.syky@sinopec.com。

中图分类号: TE121.1
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出版历程
- 收稿日期: 2015-11-27
- 修回日期: 2016-04-08
- 刊出日期: 2016-05-28

Salt tectonics and its relationship to hydrocarbon accumulation in salt basins with a lower rifted section and an upper continental marginal section: A case study of the Lower Congo-Congo Fan basins and the Kwanza Basin in West Africa

SINOPEC Petroleum Exploration and Production Research Institute, Beijing 100083, China

摘要

摘要: 西非海岸的加蓬、下刚果-刚果扇和宽扎等盆地均为典型的裂谷与被动陆缘叠合含盐含油气盆地,经历了裂谷期(早白垩世凡兰吟期-巴列姆期)、过渡期(阿普第期-早阿尔必期)和被动陆缘期(早白垩世阿尔必期-现今)3个演化阶段,沉积了裂谷期陆相地层、过渡期蒸发岩和被动陆缘期海相地层3套地层层序。古近纪以来,受非洲大陆隆升和大西洋被动陆缘持续沉降的影响,以过渡期蒸发岩为滑脱层,形成了变形特征迥异的盐上和盐下构造变形层;前者为盖层滑脱型构造,变形强烈,盐构造样式类型多样,从陆向海具有明显的构造分带特征;后者属于基底卷入型构造,变形微弱,基本保持了裂谷盆地的原始构造面貌。盐构造变形不仅控制盐上层系储层发育和圈闭形成,而且盐岩层本身又是盐下层系良好的区域盖层,尤其是盐岩层急剧增厚的深水-超深水地区,客观上对盐下和盐上油气系统具有明显的分隔作用,即盐下层系生成的油气仅在盐下层系运移聚集;但在盐岩层厚度急剧减薄或缺失的浅水至陆上地区,盐窗发育,加之断裂的垂向沟通,盐下油气可以向盐上层系运移并聚集成藏。
- 盐构造 /
- 油气成藏 /
- 裂谷 /
- 被动陆缘 /
- 叠合盆地 /
- 西非海岸
Abstract: The West African coastal basins, such as the Gabon Coastal Basin, Lower Congo Basin and Kwanza Basin, are typical oil-bearing salt basins with a lower rifted section and an upper continental marginal section. Three evolution stages can be identified in those basins, including a rifting period (the Early Cretaceous Valanginian to Barremian), a transitional period (Aptian to the early Albian) and a passive continental margin period (the early Cretaceous Albian to present), thus developing three tectono-sedimentary sequences from base to top: pre-salt, evaporites, and post-salt. On one hand, under the influence of the uplifting African craton and the continuing subsidence of the Atlantic passive margin from Paleogene to present, and taking the evaporite layer as a detachment, a gravity gliding tectonic deformation layer was formed in the post-salt sequence. This layer represents a cover-detached structure with complex deformation, various salt structural styles, and obvious tectonic zonation from east to west. On the other hand, tectonic deformation in the pre-salt tectono-sedimentary sequence was very weak, therefore, basement-related geological structures generally remained unchanged since South America and Africa separated some 165 million years ago. Salt tectonics controlled the formation and distribution of post-salt reservoirs and traps. At the same time, the salt layer works as a good regional seal for the subsalt sequence that can be interpreted as a boundary between post-salt and pre-salt petroleum systems. Therefore, in general terms, oil and gas generated in the subsalt petroleum system can only migrate and accumulate locally, particularly in deep to ultra-deep water areas where the salt strata have been thickened. However, in shallower water areas, where salt thickness was dramatically thinned or missing, subsalt oil and gas may migrate into the post-salt sequence through salt windows and/or connecting faults. Existing near-shore post-salt fields in West Africa provide support for this migration and accumulation process.
- salt tectonics /
- hydrocarbon /
- rift /
- passive margin /
- superimposed basin /
- West Africa

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参考文献(21)

[1]	冯杨伟,屈红军,张功成,等.西非被动大陆边缘构造-沉积演化及其对生储盖的控制作用[J].海相油气地质,2010,15(3):45-51. Feng Yangwei,Qu Hongjun,Zhang Gongcheng,et al.Tectonic-sedimentary evolution and its control on source-reservior-cap rocks in passive continental margin,West Africa[J].Marine Origin Petroleum Geology,2010,15(3):45-51.
[2]	汪伟光,童晓光,张亚雄,等.南大西洋重点被动大陆边缘盆地油气地质特征对比[J].中国石油勘探,2012,17(3):62-69. Wang Weiguang,Tong Xiaoguang,Zhang Yaxiong,et al.Features of major passive continental margin Basins,South Atlantic Ocean[J].China Petroleum Exploration,2012,17(3):62-69.
[3]	胡湘瑜.西非被动大陆边缘盆地群大油气田形成条件与成藏模式[J].现代地质,2013,27(1):133-142. Hu Xiangyu.Major oil and gas fields formation conditions and accumulation models of West African passive continental margin basins[J].Geoscience,2013,27(1):133-142.
[4]	冯国良,徐志诚,靳久强,等.西非海岸盆地群形成演化及深水油气田发育特征[J].海相油气地质,2012,17(1):23-28. Feng Guoliang,Xu Zhicheng,Jin Jiuqiang,et al.Basin evolution and development characteristics of deepwater oil and gas fields in coastal basins,West Africa[J].Marine Origin Petroleum Geo-logy,2012,17(1):23-28.
[5]	熊利平,王骏,殷进垠,等.西非构造演化及其对油气成藏的控制作用[J].石油与天然气地质,2005,26(5):641-646. Xiong Liping,Wang Jun,Yin Jinyin,et al.Tectonic evolution and its control on hydrocarbon accumulation in West Africa[J].Oil & Gas Geology,2005,26(5):641-646.
[6]	McHargue T R.Stratigraphic development of Proto-South Atlantic rifting in Cabinda,Angola:A petroliferous lake basin[M]//Katz B J.Lacustrine basin exploration:Case studies and modern analogs.Tulsa:AAPG,1990:307-326.
[7]	Brice S E,Cochran M D,Pardo G,et al.Tectonics and sedimentation of the South Atlantic rift sequence:Cabinda,Angola[M]//Watkins J S,Drake C L.Studies in continental margin geology.Tulsa:AAPG,1982:5-18.
[8]	Valle P J,Gjelberg J G,Helland-Hansen W.Tectonostratigraphic development in the eastern Lower Congo Basin,offshore Angola,West Africa[J].Marine and Petroleum Geology,2001,18(8):909-927.
[9]	Guevara M,Hawkins L,Joaquim L,et al.Structural development and depositional history of the Lower Congo and Kwanza Basins Salt Tectonic Province,Angola[C]//AAPG international confe-rence and exhibition.Rio de Janeiro:AAPG,2009.
[10]	Duval B,Cramez C,Jackson M P A.Raft tectonics in the Kwanza Basin,Angola[J].Marine and Petroleum Geology,1992,9(4):389-404.
[11]	Fort X,Brun J P,Chauvel F.Salt tectonics on the Angolan margin,synsedimentary deformation processes[J].AAPG Bulletin,2004,88(11):1523-1544.
[12]	Spathopoulos F.An insight on salt tectonics in the Angola Basin,South Atlantic[M]//Alsop G I,Blundell D J,Davison I.Salt tectonics.London:Special Publication of Geological Society,1996:153-174.
[13]	Marton L G,Tari G C,Lehmann C T.Evolution of the Angolan Passive Margin Basin,West Africa,with emphasis on post-salt structural styles[M]//Mohriak W,Taiwani M.Atlantic rifts and continental margins:Geophysical Monograph Series 115.[S.l.]:American Geophysical Union,2000:129-149.
[14]	李涛,胡望水,于水,等.西非被动大陆边缘重力滑脱构造体系下的塑性构造[J].海洋地质与第四纪地质,2012,32(3):69-76. Li Tao,Hu Wangshui,Yu Shui,et al.Ductile structures in gravitational decollement structure system at passive continental margin of West Africa[J].Marine Geology & Quaternary geology,2012,32(3):69-76.
[15]	Hudec M R,Jackson M P A.Regional restoration across the Kwanza Basin,Angola:Salt tectonics triggered by repeated uplift of a metastable passive margin[J].AAPG Bulletin,2004,88(7):971-990.
[16]	赵灿,郑荣才,于水,等.下刚果盆地A区块下白垩统阿尔布阶混积相研究[J].岩性油气藏,2011,23(3):84-90. Zhao Can,Zheng Rongcai,Yu Shui,et al.Study on mixed sedimentary facies of Lower Cretaceous Albian in block A of Lower Cong Basin[J].Lithologic Reservoirs,2011,23(3):84-90.
[17]	Anderson J E,Cartwright J,Drysdall S J,et al.Controls on turbidite sand deposition during gravity-driven extension of a passive margin:Examples from Miocene sediments in Block 4,Angola[J].Marine and Petroleum Geology,2001,17(10):1165-1203.
[18]	Katz B J,Mello M R.Petroleum systems of South Atlantic marginal basins:An overview[M]//Mello M R,Katz B J.Petroleum systems of south atlantic margins.Tulsa:AAPG,2000:1-13.
[19]	郑应钊,何登发,马彩琴,等.西非海岸盆地带大油气田形成条件与分布规律探析[J].西北大学学报(自然科学版),2011,41(6):1018-1024. Zheng Yingzhao,He Dengfa,Ma Caiqin,et al.The forming factors and distribution rules of giant oil and gas fields in the coas-tal basins of West Africa[J].Journal of Northwest University(Natural Science Edition),2011,41(6):1018-1024.
[20]	杨永才,张树林,孙玉梅,等.西非宽扎盆地烃源岩分布及油气成藏[J].海洋地质前沿,2013,29(3):29-36. Yang Yongcai,Zhang Shulin,Sun Yumei,et al.Source rock distribution and petroleum accumulation in Kwanga Basin,West Africa[J].Marine Geology Frontier,2013,29(3):29-36.
[21]	Dale C T,Lopes J R,Abilio S.Takula oil field and the Greater Takula area,Cabinda,Angola[M]//Halbouty M T.Giant oil and gas fields of the decade 1978-1988.Tulsa:AAPG,1992:197-215.