Submarine-fan reservoir architecture of deepwater gasfield X in Rovuma Basin offshore East Africa: insights for the interaction between sediment gravity flows and bottom currents
ZHANG Jiajia1,2, WU Shenghe1,2, WANG Ruifeng3, WANG Min3, CHEN Mei1,2, WANG Xiaofeng4, XU Qingyan3, XIONG Qicong1,2, YU Jitao1,2, WANG Li3
1 College of Geosciences,China University of Petroleum(Beijing),Beijing 102249,China; 2 State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum(Beijing), Beijing 102249,China; 3 Research Institute of Petroleum Exploration and Development,PetroChina, Beijing 100083,China; 4 CNODC Mozambique Ltd.,Company, Beijing 100034,China
Abstract：Bottom currents are common phenomenon in the deepwater setting of continental margins,which have important impacts on the deepwater sedimentary process and sandstone distribution. Extensive studies have been focused on the mechanisms and sedimentary products of gravity flow-bottom current interaction,but it remains much unknown regarding the submarine-fan reservoir architecture model modified by bottom currents. The Rovuma Basin offshore East Africa is a typical region to study the interaction between sediment gravity flows and bottom currents. Taking the representative submarine channel systems from the Lower Eocene as an example,this paper characterizes the reservoir architecture by integrating cores,well logs and 3D seismic data,with an aim to establish the submarine channel architecture model under interaction of sediment gravity flows with bottom currents. Results show that the target channel system developed three types of architectural elements,channel,overbank,and lobe,where channel deposits contain channel complexes, individual channels,and other smaller hierarchical units. Fine-grained materials could be transported by bottom currents forming asymmetrical distribution of overbanks deposits. This forced channel complexes to migrate laterally against bottom currents,with shale barriers easily preserved. Individual channels show downstream migration or lateral migration against bottom currents. In downstream migration,channels incised each other forming good sand connectivity,while indined shale baffles may develop in lateral migration. As influenced by sediment gravity flows,individual channel-fills evolved from mixed sand-shale to sand-prone channels,and in the mapview sandbodies are mostly distributed in the axis of channel bends.
ZHANG Jiajia,WU Shenghe,WANG Ruifeng et al. Submarine-fan reservoir architecture of deepwater gasfield X in Rovuma Basin offshore East Africa: insights for the interaction between sediment gravity flows and bottom currents[J]. JOPC, 2023, 25(1): 163-179.
[1] 曹全斌,唐鹏程,吕福亮,范国章,邵大力,鲁银涛,许小勇,陈宇航. 2018. 东非鲁伍马盆地深水浊积砂岩气藏成藏条件及控制因素. 海相油气地质, 23(3): 67-74. [Cao Q B,Tang P C,Lü F L,Fan G Z,Shao D L,Lu Y T,Xu X Y,Chen Y H. 2018. Formation conditions and controlling factors of gas-bearing turbidite sand reservoirs in deep water deposits in the Rovuma Basin,East Africa. Marine Origin Petroleum Geology, 23(3): 67-74] [2] 陈宇航,姚根顺,吕福亮,唐鹏程,鲁银涛. 2016. 东非鲁伍马盆地深水区构造-沉积演化过程及油气地质特征. 海相油气地质, 21(2): 39-46. [Chen Y H,Yao G S,Lü F L,Tang P C,Lu Y T. 2016. Tectonic-sedimentary evolution and petroleum geology characteristics in deepwater area in Rovuma Basin,East Africa. Marine Origin Petroleum Geology, 21(2): 39-46] [3] 孔祥宇. 2013. 东非鲁伍马盆地油气地质特征与勘探前景. 岩性油气藏, 25(3): 21-27. [Kong X Y. 2013. Petroleum geologic characteristics and exploration prospect in Rovuma Basin,East Africa. Lithologic Reservoirs, 25(3): 21-27] [4] 李华,王英民,徐强,卓海腾,吴嘉鹏,唐武,李冬,徐艳霞. 2014. 南海北部珠江口盆地重力流与等深流交互作用沉积特征、过程及沉积模式. 地质学报, 88(6): 1120-1129. [Li H,Wang Y M,Xu Q,Zhuo H T,Wu J P,Tang W,Li D,Xu Y X. 2014. Interactions between down-slope and along-slope processes on the northern slope of South China Sea: products,processes,and depositional model. Acta Geologica Sinica, 88(6): 1120-1129] [5] 林煜,吴胜和,王星,路瑶,万琼华,张佳佳,张义楷. 2013. 深水浊积水道体系构型模式研究: 以西非尼日尔三角洲盆地某深水研究区为例. 地质论评, 59(3): 510-520. [Lin Y,Wu S H,Wang X,Lu Y,Wan Q H,Zhang J J,Zhang Y K. 2013. Research on architecture model of deepwater turbidity channel system: a case study of a deepwater research area in Niger Delta Basin,West Africa. Geological Review, 59(3): 510-520] [6] 刘飞,赵晓明,冯潇飞,葛家旺,杨莉,杨宝泉,杨希濮. 2021. 基于重力流相的深水水道分类方案研究. 古地理学报, 23(5): 951-965. [Liu F,Zhao X M,Feng X F,Ge J W,Yang L,Yang B Q,Yang X P. 2021. Research on classification of deep-water channels based on gravity flow facies. Journal of Palaeogeography(Chinese Edition), 23(5): 951-965] [7] 王敏,张佳佳,王瑞峰,徐庆岩,文思颖,曹全斌,余季陶,王黎. 2022. 鲁伍马盆地 X 气田深水海底扇储集层质量差异及主控因素分析. 石油勘探与开发, 49(3): 1-11. [Wang M,Zhang J J,Wang R F,Xu Q Y,Wen S Y,Cao Q B,Yu J T,Wang L. 2022. Quality variations and controlling factors of deepwater submarine-fan reservoirs in X gas field,Rovuma Basin,East Africa. Petroleum Exploration and Development, 49(3): 1-11] [8] 张光亚,刘小兵,赵健,温志新,张荻萩,王兆明,张磊,马锋,陈曦. 2018. 东非被动大陆边缘盆地演化及大气田形成主控因素: 以鲁武马盆地为例. 地学前缘, 25(2): 24-32. [Zhang G Y,Liu X B,Zhao J,Wen Z X,Zhang D Q,Wang Z M,Zhang L,Ma F,Chen X. 2018. Passive continental margin basin evolution of East Africa and the main controlling factors of giant gas fields: an example from the Rovuma Basin. Earth Science Frontiers, 25(2): 24-32] [9] 赵晓明,吴胜和,刘丽. 2012. 尼日尔三角洲盆地Akpo油田新近系深水浊积水道储层构型表征. 石油学报, 33(6): 1049-1058. [Zhao X M,Wu S H,Liu L. 2012. Characterization of reservoir architectures for Neogene deepwater turbidity channels of Akpo oilfield,Niger Delta Basin. Acta Petrolei Sinica, 33(6): 1049-1058] [10] Breitzke M,Wiles E,Krocker R,Watkeys M K,Jokat W. 2017. Seafloor morphology in the Mozambique Channel: evidence for long-term persistent bottom-current flow and deep-reaching eddy activity. Marine Geophysical Research, 38(3): 241-269. [11] Cavanna G,Castoro A,Fervari. 2014. Hydrocarbon and lithology indicators by coordinate rotations in the AI-Vop/vs domain. In: 76th EAGE Conference & Exhibition 2014. June,Amsterdam RAI. The Netherlands: 16-19. [12] Chen Y H,Yao G S,Wang X F,Lü F L,Shao D L,Lu Y T,Cao Q B,Tang P C. 2020. Flow processes of the interaction between turbidity flows and bottom currents in sinuous unidirectionally migrating channels: an example from the Oligocene channels in the Rovuma Basin,offshore Mozambique. Sedimentary Geology, 404: 1-13. [13] Deptuck M E,Steffens G S,Barton M,Pirmez C. 2003. Architecture and evolution of upper fan channel-belts on the Niger Delta slope and in the Arabian Sea. Marine and Petroleum Geology, 20(6-8): 649-676. [14] de Ruijter W P,Ridderinkhof H,Lutjeharms J R,Schouten M W,Veth C. 2002. Observations of the flow in the Mozambique channel. Geophysical Research Letters, 29(10): 140-1-140-3. [15] Fonnesu M,Palermob D,Galbiati M,Marchesini M,Bonamini E,Bendias D. 2020. A new world-class deep-water play-type,deposited by the syndepositional interaction of turbidity flows and bottom currents: the giant Eocene Coral Field in northern Mozambique. Marine and Petroleum Geology, 111: 179-201. [16] Fuhrmann A,Kane I A,Clare M A,Ferguson R A,Schomacker E,Bonamini E,Contreras F A. 2020. Hybrid turbidite-drift channel complexes: an integrated multiscale model. Geology, 48(6): 562-568. [17] Gong C L,Wang Y M,Zhu W L,Li W G,Xu Q. 2013. Upper Miocene to quaternary unidirectionally migrating deep-water channels in the Pearl River Mouth basin,northern South China Sea. AAPG Bulletin, 97(2): 285-308. [18] Gong C L,Wang Y M,Rebesco M,Salon S,Steel R J. 2018. How do turbidity flows interact with contour currents in unidirectionally migrating deep-water channels? Geology, 46(6): 551-554. [19] Labourdette R. 2007. Integrated three-dimensional modeling approach of stacked turbidite channels. AAPG Bulletin, 91(11): 1603-1618. [20] Lin Y,Wu S H,Wang X,Ling Y,Lu Y,Zhang J J,Yu Z. 2014. Composite sand bodies architecture of deep-water turbidite channels in the Niger Delta Basin. Acta Geologica Sinica, 88(6): 1822-1834. [21] Lowe D R. 1982. Sediment gravity flows;Ⅱ,depositional models with special reference to the deposits of high-density turbidity currents. Journal of Sedimentary Research, 52(1): 279-297. [22] Mayall M,Jones E,Casey M. 2006. Turbidite channel reservoirs: key elements in facies prediction and effective development. Marine and Petroleum Geology, 23(8): 821-841. [23] Miramontes E,Eggenhuisen J T,Jacinto R S,Poneti G,Pohl F,Normandeau A,Campbell D C,Hernández-Molina F J. 2020. Channel-levee evolution in combined contour current-turbidity current flows from flume-tank experiments. Geology, 48(4): 353-357. [24] Palermo D,Galbiati M,Famiglietti M,Marchesini M,Mezzapesa D,Fonnesu F. 2014. Insights into a new super-giant gas field-sedimentology and reservoir modeling of the coral reservoir complex,offshore northern Mozambique. In: Offshore Technology Conference-Asia,25-28 March,Kuala Lumpur,Malaysia. [25] Peakall J,McCaffrey B,Kneller B. 2000. A process model for the evolution,morphology,and architecture of sinuous submarine channels. Journal of Sedimentary Research, 70(3): 434-448. [26] Piper D J,Normark W R. 1983. Turbidite depositional patterns and flow characteristics,Navy submarine fan,California Borderland. Sedimentology, 30(5): 681-694. [27] Posamentier H W,Kolla V. 2003. Seismic geomorphology and stratigraphy of depositional elements in deep-water settings. Journal of sedimentary Research, 73(3): 367-388. [28] Shanmugam G. 2016. Submarine fans: a critical retrospective(1950-2015). Journal of Palaeogeography, 5(2): 110-184. [29] Sprague A R,Sullivan M D,Campion K M,Jensen G N,Goulding D K,Sickafoose D K,Jennette D C. 2002. The physical stratigraphy of deep-water strata: a hierarchical approach to the analysis of genetically related elements for improved reservoir prediction. In: American Association of Petroleum Geologists Annual Meeting Abstracts,Houston,Texas: 10-13. [30] Zhang J J,Wu S H,Wang X,Lin Y,Fang H J,Jiang L,Wang Q H,Yin H,Lu Y. 2015. Reservoir quality variations within a sinuous deep water channel system in the Niger Delta Basin,offshore West Africa. Marine and Petroleum Geology, 63: 166-188. [31] Zhang J J,Wu S H,Hu G Y,Fan T E,Yu B,Lin P,Jiang S N. 2018. Sea-level control on the submarine fan architecture in a deepwater sequence of the Niger Delta Basin. Marine and Petroleum Geology, 94: 179-197. [32] Wynn R B,Masson D G. 2008. Sediment waves and bedforms. In: Rebesco M,Camerlenghi A(eds). Contourites,Developments in Sedimentology,vol. 60. Elsevier,Amsterdam: 289-300.
