DUCTILE STRUCTURES IN GRAVITATIONAL DECOLLEMENT STRUCTURE SYSTEM AT PASSIVE CONTINENTAL MARGIN OF WEST AFRICAN
-
摘要: 论述了西非被动大陆边缘深水环境下的重力滑脱构造体系中的塑性构造。研究发现塑性地层在整个西非被动大陆边缘都有分布,且盐岩塑性层主要分布在西非被动大陆边缘的西南部和西北部,发育层位为过渡期(J-K)构造层之内;中部尼日尔三角洲等塑性层主要为泥岩塑性层,发育层位为古近系和新近系。根据重力滑脱构造体系发育特征可划分为:以正断裂和塑性焊接构造为主的上部重力滑脱伸展构造、以底辟构造为主的中部重力滑脱底辟构造、以冲断裂、塑性褶皱和塑性冲断构造为主的下部重力滑脱冲断构造。根据塑性构造上覆地层的变形过程,塑性构造演化主要经历了后生变形期和同生变形期。塑性构造变形机制主要受基底掀斜作用和上覆地层的沉积速率控制。塑性构造中的底辟、褶皱、冲断及塑性焊接构造对油气成藏的控制作用依次减弱。Abstract: This article deals with the ductile structures in the deep-water gravitational decollement structure system at the Passive Continental Margin of West African. It is found that ductile structures are widely distributed along the whole passive continental margin, and the ductile salt rocks are particularly developed in the southwest and northwest within the transitional structural layer (J-K). In the Niger delta at the middle part of the passive margin of West Africa, ductile bed is mainly consisting of mudstone of Tertiary. According to the structural characteristics of the gravitational detachment structure system, the ductile structures could be divided into three types:the gravitational decollement extensional structures at the upper part characterized by normal fault and ductile; the gravitational decollement diapir structures at the middle part; and the gravitational decollement thrust structures at the lower part. According to the time of deformation of the ductile structure, the ductile structures could be grouped into two types of epigenetic and syngenetic structures. Deformation of ductile beds is mainly affected by the basement tilting and deposition rate of the overlying strata. The control of structures over oil and gas accumulation decreases in an order of diapir, fold, thrust and ductile welding structure.
-
Keywords:
- ductile structure /
- ductile deformation /
- gravity slip /
- West Africa
-
-
[1] 吕福亮,何训云,等.世界深水油气勘探形势分析及对我国深水油气勘探的启示[J].海洋石油,2007,27(3):41-45. [LV Fuliang, HE Xunyun.The current situation and trend of deepwater oil and gas exploration of the world and the inspiration for us[J].Offshore Oil,2007,37(3):41-45.]
[2] 周蒂,孙珍,陈汉宗.世界著名深水油气盆地的构造特征及对我国南海北部深水油气勘探的启示[J].地球科学进展,2007,22(6):561-570. [ZHOU Di,SUN Zhen,CHEN Hanzong. Tectonic features of world's major deep-water oil/gas fields and their enlightenment to deep-water exploration in northern South China Sea[J]. Advances in Earth Science,2007,22(6):561-570.]
[3] 林闻,周金应.世界深水油气勘探新进展与南海北部深水油气勘探[J].石油物探,2009,48(6):601-605. [LIN Wen,ZHOU Jinying. Progress of deepwater hydrocarbon exploration worldwide and the exploration in the deepwater region of northern South China Sea[J].Geophysical Prospecting for Petroleum, 2009, 48(6):601-605.]
[4] 贾承造,赵文智,魏国齐,等.盐构造与油气勘探[J].石油勘探与开发,2003,30(2):17-19. [JIA Chengzao, ZHAO Wenzhi, WEI Guoqi, et al. Salt structures and exploration of oil and gas[J]. Petroleum Exploration and Development, 2003,30(2):17-19.]
[5] Armentrout J M. Kanschat K A, Meisling K E, et al. Neogene turbidite systems of the Gulf of Guinea continental margin slope, offshore Nigeria[C]//Fine-grained turbidite systems. AAPG Memoir 72 and SEPM Special Publication, 2000,68:93108.
[6] Doust H. Omatsola E. Niger Delta[C]//Divergent/Passive Margin Basins. AAPG Memoir, 1990, 48:201-238.
[7] Marton G, Tari G Lehmann C. Evolution of the Angolan passive margin, West Africa, with emphasis on post-salt structural styles[C]//Atlantic Rifts and Continental Margins. American Geophysical Union, Geophysical Monograph Series, 2000,115:129-149.
[8] Tari,G Molnai J Ashton P. Examples of salt tectonics from West Africa:a comparative approach[C]//New Themes and Developing Technologies. Geological Society, London, Special Publications, 2003, 207:85-104.
[9] Jose de Vera, Pablo Granado. Structural evolution of the Orange Basin gravity-driven system, offshore Namibia[J]. Marine and Petroleum Geology,2010,27:223-237.
[10] Coward M P, Purdy E G, Ries A C,et al, The distribution of petroleum reserves in basins of the South Atlantic margins[C]//The oil and gas habitats of the South Atlantic. Geological Society of London, 1999,153(Special Publication):101-151.
[11] Brownfield M E, Charpentier R R. Geology and total petroleum systems of the Gulf of Guinea Province of West Africa[C]. USGS Bulletin 2207-CU.S, Posted online July 2006 Version 1.0.
[12] Brownfield M E, Charpentier R R. Assessment of the undiscovered oil and gas of the Senegal province, Mauritania, Senegal, The Gambia, and Guinea-Bissau, Northwest Africa[C]. USGS Bulletin 2207 A, Posted online October 2003, version 1.0.
[13] Spathopoulos F. An insight on salt tectonics in the Angola Basin, South Atlantic[C]//Salt tectonics:Geological Society (London) Special Publication, 1996, 100:153-174.
[14] Xavier Fort, Jean-Pierre Brun, Francois Chauvel.Salt tectonics on the Angolan margin, synsedimentary deformation processes[J].AAPG Bulletin, 2004,88(11):1523-1544.
[15] 胡望水,薛天庆. 底辟构造成因类型[J].江汉石油学院学报,1997,19(4):1-7. [HU Wangshui, XUE Tianqing. Genetic types of diapiric structures[J]. Journal of Jianghan Petroleum Institute, 1997,19(4):1-7.]
[16] Martin P A Jackson,Michael R Hudec, et al. Evolution of the Cretaceous Astrid thrust belt in the ultradeep-water Lower Congo Basin, Gabon[J]. AAPG Bulletin, 2008,92(4):487-511.
[17] Zahie Anka, Michel Se'ranne. Evidence of a large upper-Cretaceous depocentre across the Continent-Ocean boundary of the Congo-Angola basin. Implications for palaeo-drainage and potential ultra-deep source rocks[J]. Marine and Petroleum Geology,2010,27:601-611.
[18] Zahie Anka,Michel Séranne. The long-term evolution of the Congo deep-sea fan:A basin-wide view of the interaction between a giant submarine fan and a mature passive margin (ZaiAngo project)[J]. Tectonophysic,2009,470:42-56.
计量
- 文章访问数: 1923
- HTML全文浏览量: 245
- PDF下载量: 8
下载:
