Accumulation conditions of far-source lithologic reservoirs and exploration strategy in Melut Basin, Central Africa

doi:10.3969/j.issn.1672-7703.2017.06.010

Abstract

Abstract: Systematic studies have been carried out on the conditions and characteristics of the Paleogene far-source hydrocarbon accumulation and the exploration strategy in the Melut Basin, Central Africa, and state that the strong differentiation of rifting and sagging is the main controlling factor on the development of the sandstone-rich formations and far-source reservoirs.The delta front facies in the upper Paleogene Yabus Formation is developed with shallow buried depth and good reservoir properties, and favorable for forming high-productivity reservoirs, so it is the ideal target for discovering commercial lithologic reservoirs in the Melut Basin. The oil source condition is the key factor on the Paleogene far-source hydrocarbon accumulation,and the structural-lithologic traps controlled by oil-migrating faults are favorable traps.Based on the study on oil-water contact and hydrocarbon detection, discovered structural traps with oil-water contacts over over-flowing points were selected as initial targets for exploring far-source lithologic and structural-lithologic traps. This may reduce exploration risk and increase drilling success rate. This paper proposes favorable far-source lithologic reservoirs and their controlling factors, accumulation characteristics and exploration technology, expands the exploration field and provides technical support for the exploration of the Paleogene far-source lithologic and structural-lithologic traps in the developed northern exploration block in the Melut Basin.

Key words: Central Africa, Melut Basin, Paleogene, far-source lithologic reservoirs, exploration strategy

CLC Number:

TE112.3

Shi Zhongsheng, Xue Luo, Niu Huiyun, Wang Guolin, Chen Bintao, He Weiwei, Ma Lun. Accumulation conditions of far-source lithologic reservoirs and exploration strategy in Melut Basin, Central Africa[J]. China Petroleum Exploration, 2017, 22(6): 87-95.

References

[1] Rosendahl B R. Architecture of continental rifts with special reference to East Africa[J]. Annual Review Earth Planetary Science,1987,15:445-503.
[2] Lowell J D. Structural styles in petroleum exploration[M]. Tulsa, Oklahoma, Oil and Gas Consultants International Inc. 1985,477.
[3] 杜金虎,何海清,赵贤正,张以明,王权,张锐锋,等. 渤海湾盆地廊固凹陷杨税务超深超高温奥陶系潜山油气勘探重大突破实践与启示[J]. 中国石油勘探,2017,22(2):1-12. Du Jinhu, He Haiqing, Zhao Xianzheng, Zhang Yiming, Wang Quan, et al. Significant exploration breakthrough in Yangshuiwu ultra-deep and ultra-high temperature Ordovician buried-hill in Langgu sag, Bohai Bay Basin[J]. China Petroleum Exploration, 2017,22(2):1-12.
[4] 赵贤正,周立宏,蒲秀刚,肖敦清,姜文亚,韩文中,等. 断陷湖盆斜坡区油气富集理论与勘探实践——以黄骅坳陷古近系为例[J]. 中国石油勘探,2017,22(2):13-24. Zhao Xianzheng, Zhou Lihong, Pu Xiugang, Xiao Dunqing, Jiang Wenya, Han Wenzhong, et al. Hydrocarbon enrichment theory and exploration practice in the slope of fault lake basin-a case study of Paleogene in Huanghua depression[J]. China Petroleum Exploration, 2017,22(2):13-24.
[5] 武龙,闫兵,李海滨,李一泉,王毛毛.全球大型油气田的盆地类型与分布规律[J].高校地质学报,2011,17(2):170-184. Wu Long, Yan Bin, Li Haibin, Li Yiquan, Wang Maomao. Basin types and distribution of the global giant oil and gas fields[J]. Geological Journal of China Universities, 2011,17(2):170-184.
[6] 汤戈,孙志华,苏俊青,唐鑫萍. 西非Termit盆地白垩系层序地层与沉积体系研究[J]. 中国石油勘探,2015,20(4):81-88. Tang Ge, Sun Zhihua, Su Junqing, Tang Xinping. Study of Cretaceous sequential stratigraphy and sedimentary system in Termit Basin of West Africa[J]. China Petroleum Exploration, 2015,20(4):81-88.
[7] 刘淑文,李志,潘校华,客伟利,胡胜福,张新顺. 苏丹富油气凹陷岩性油气藏区带评价探讨——以Muglad盆地Fula凹陷为例[J]. 中国石油勘探,2017,22(2):90-98. Liu Shuwen, Li Zhi, Pan Xiaohua, Ke Weili, Hu Shengfu, Zhang Xinshun. Play evaluation on lithologic reservoirs in hydrocarbon-rich sags in Sudan:a case study on Fula sag, Muglad Basin[J]. China Petroleum Exploration, 2017,22(2):90-98.
[8] 窦立荣.苏丹迈努特盆地油气成藏机理和成藏模式[J].矿物岩石地球化学通报,2005,24(1):50-57. Dou Lirong. Formation mechanism and model of oil and gas accumulations in the Melut Basin, Sudan[J].Bulletin of Mineralogy Petrology and Geochemistry, 2005,24(1):50-57.
[9] 张运东,薛红兵,朱如凯,高朝阳.国内外隐蔽油气藏勘探现状[J]. 中国石油勘探,2005,10(3):64-68. Zhang Yundong, Xue Hongbing, Zhu Rukai, Gao Chaoyang. Development status of exploration techniques on subtle oil-gas reservoir at home and abroad[J].China Petroleum Exploration,2005,10(3):64-68.
[10] 赵贤正,田福清,王权,范炳达,董雄英,赵淑芳,等. 老区富油凹陷"五精一创"勘探实践与启示[J]. 中国石油勘探,2016,21(6):1-8. Zhao Xianzheng,Tian Fuqing,Wang Quan,Fan Bingda,Dong Xiongying,Zhao Shufang, et al. Application and performance of delicate and innovative exploration practices in oil-rich sags of matured areas[J]. China Petroleum Exploration, 2016,21(6):1-8.
[11] 贾承造,赵文智,邹才能,冯志强,袁选俊,池英柳,等.岩性地层油气藏地质理论与勘探技术[J].石油勘探与开发,2007,34(3):257-272. Jia Chengzao, Zhao Wenzhi, Zou Caineng, Feng Zhiqiang, Yuan Xuanjun, Chi Yingliu, et al. Geological theory and exploration technology for lithostratigraphic hydrocarbon reservoirs[J].Petroleum Exploration and Development, 2007, 34(3):257-272.
[12] Schull T J. Rift basins of Interior Sudan:Petroleum exploration and discovery[J]. AAPG Bulletin 1988,72(10):1128-1142.
[13] Genik G J. Petroleum Geology of Cretaceous-Tertiary Rift Basins in Niger, Chad, and Central African Republic[J]. AAPG Bulletin, 1993,77(8):1405-1434.
[14] Mchargue T R, Heidrick T L, Livingston Jack E. Tectonostratigraphic development of the Interior Sudan rifts, Central Africa[J]. Tectonophysics, 1992,213(1/2):187-202.
[15] Jorgensen, G J, Bosworth, W. Gravity modeling in the central African rift system, Sudan:rift geometries and tectonic significance[J]. Journal of African Earth Science, 1989,8(2/3/4):283-306.
[16] Turcotte D L, Emermann S H. Mechanisms of active and passive rifting[J]. Tectonophysics, 1983,94(1):39-50.
[17] Sengor A M C, Burke K. Relative timing of rifting and volcanism on Earth and its tectonic implications[J]. Geophysical Research Letters, 1978,5(6):419-421.
[18] Morgan P, Baker B H. Introduction-Processes of continental rifting[J]. Tectonophysics, 1983,94:1-10.
[19] 窦立荣,潘校华,田作基,肖坤叶,张志伟. 苏丹裂谷盆地油气藏的形成与分布——兼与中国东部裂谷盆地对比分析[J].石油勘探与开发, 2006,33(3):255-261. Dou Lirong, Pan Xiaohua, Tian Zuoji, Xiao Kunye, Zhang Zhiwei. Hydrocarbon formation and distribution of rift basins in Sudan-a comparative analysis of them with rift basins in East China[J]. Petroleum Exploration and Development, 2006, 33(3):255-261.
[20] 欧阳文生,张枝焕,陆黄生,张明华,程言东.储集层沉积的两种极端模式——主动裂谷和被动裂谷[J].石油勘探与开发,2007, 34(6):687-690. Ouyang Wensheng, Zhang Zhihuan, Lu Huangsheng, Zhang Minghua, Cheng Yandong. Two extreme modes of reservoir sedimentation:active rift and passive rift[J]. Petroleum Exploration and Development, 2007,34(6):687-690.
[21] 贾承造,赵文智,邹才能,袁选俊,陶世振,池英柳,等.岩性地层油气藏地质理论与勘探技术[M]. 北京:石油工业出版社,2008:81. Jia Chengzao, Zhao Wenzhi, Zou Caineng, Yuan Xuanjun, Tao Shizhen, Chi Yingliu, et al. Geological theory and exploration technology for lithostratigraphic hydrocarbon reservoirs[M]. Beijing:Petroleum Industry Press, 2008:81.
[22] 史忠生,王天琦,方乐华,李娟,白洁,何巍巍,等.从类比中探索Muglad与Melut两大盆地勘探潜力与转型[J].中国石油勘探, 2014,19(2):67-75. Shi Zhongsheng, Wang Tianqi, Fang Lehua, Li Juan, Bai Jie, He Weiwei, et al. Study exploration potential and transformation of Muglad Basin and Melut Basin on basis of analogy[J].China Petroleum Exploration, 2014,19(2):67-75.
[23] 童晓光,徐志强,史卜庆,窦立荣,肖坤叶.苏丹迈卢特盆地石油地质特征及成藏模式[J].石油学报,2006,27(2):1-10. Tong Xiaoguang, Xu Zhiqiang, Shi Buqing, Dou Lirong, Xiao Kunye. Petroleum geologic property and reservoir-forming pattern of Melut Basin in Sudan[J]. Acta Petrolei Sinica, 2006,27(2):1-10.
[24] 陈云林.论富油洼陷及其意义[J].勘探家,1999,4(2):8-11. Chen Yunlin. Concept of oil-rich subsag and its significance[J].Petroleum Explorationist, 1999,4(2):8-1.
[25] 赵文智,邹才能,汪泽成,李建忠,李明,牛嘉玉.富油气凹陷"满凹含油"论——内涵与意义[J].石油勘探与开发,2004,31(2):5-13. Zhao Wenzhi, Zou Caineng, Wang Zecheng, Li Jianzhong, Li Ming, Niu Jiayu. The intension and signification of"Sag-wide Oil-Bearing Theory"in the hydrocarbon-rich depression with terrestrial origin[J].Petroleum Exploration and Development, 2004,31(2):5-13.