Citation: | WANG Hongyu, ZHANG Feng, CAI Yuwei. Sedimentary evolution of the passive continental margin of the north sub-basin, Senegel Basin and its controlling factors[J]. Marine Geology & Quaternary Geology, 2020, 40(4): 67-77. doi: 10.16562/j.cnki.0256-1492.2019081501 |
The north sub-basin of the Senegel Basin is a rift and passive continental margin superimposed basin along the Atlantic coast of Northwest Africa. It is characterized by multiple types of continental slopes, well-developed carbonate sediments and relatively underdeveloped salt structures. Based on the seismic and drilling data of the southern area of the sub-basin, this paper analyzed the paleogeomorphic evolution of the continental slope and the sedimentary filling history during the development period as a passive continental margin basin. Main controlling factors for the geological characteristics of the sub-basin are discussed in the paper. The study reveals that during Cretaceous, the continental slope of the study area had experienced several phases of evolution, from the platform margin slope, to the syndepositional fault slope, and to the broad and gentle sedimentary slope, corresponding to the tectono-sedimentary evolution stages: the carbonate platform construction stage of early Cretaceous, the Albian-Santonian stages while the clastic deposits area be separated into internal and external areas by fault slope, and the Campanian-Maastrichtian stages dominated by a gentle slope covered by clastic deposits. Sediment distributions in different stages show different depositional patterns. Global sea level changes and relatively insufficient supply of terrigenous clastic are important factors for the sediment filling features of the passive continental margin basin in the study area. Regional tectonic activities have a direct impact over the evolution of landform, the occurrence of unconformity and the movement of provenance back and forth in the study area. The paleoclimate and provenance conditions have indirect influences on the type, scale and sediment depositional pattern in the basin.
[1] | Abdelrahman E M, Tealeb A, Hassan R M. A least-squares derivative analysis of gravity data applied in Senegal, West Africa [J]. Journal of African Earth Sciences, 2001, 33(1): 165-175. doi: 10.1016/S0899-5362(01)90097-1 |
[2] | Brownfield M E, Ronald R Charpentier. Assessment of the Undiscovered Oil and Gas of the Senegal Province, Mauritania, Senegal, The Gambia, and Guinea-Bissau, Northwest Africa[R]. U. S. Geological Survey Bulletin 2207-A. Posted online October 2003, version 1.0. Published in the Central Region, Denver, Colorado. Manuscript approved for publication June 5, 2003. |
[3] | IHS Energy Group. Basin monitor of Senegal(M. S. G. B. C)Basin(Mauritania, Senegal, Guinea-Bissau, Guinea, Guinea-Bissau/Senegal JEZ, Cape Verde, Western Sahara, Gambia, North Atlantic Ocean Region, Sierra Leone)[DB/OL]. 2012, http://energy.ihs.com/. |
[4] | Faye M, Hameh P, Rochet J. New concepts on the geology of palaeozoic and post Hercynian formation in the Basin of Senegal [C] // European Association of Petroleum Geologists 4th Conference, Poster Abstract, Paris, France, 1992: 176-177. |
[5] | Reymond A. Oil reservoir character in northwest Africa including Mauritania, Senegal and Guinea Bissau [J]. World Oil, 1989, 208(6): 53-57. |
[6] | 刘延莉. 塞内加尔盆地油气地质特征及勘探潜力[J]. 地质与资源, 2014, 23(2):197-201 LIU Yanli. The petroleum geology prospective analysis of the Senegal basin [J]. Geology and Resources, 2014, 23(2): 197-201. |
[7] | 孙涛, 王建新, 孙玉梅. 西非塞内加尔盆地深水区油气地球化学特征与油气成藏[J]. 沉积学报, 2017, 35(6):1284-1292 SUN Tao, WANG Jianxin, SUN Yumei. Petroleum Geochemical Characteristics and Accumulation in Offshore of Senegal Basin [J]. Acta Sedimentologica Sinica, 2017, 35(6): 1284-1292. |
[8] | 王大鹏, 殷进垠, 田纳新, 等. 塞内加尔盆地成藏组合划分与资源潜力评价[J]. 现代地质, 2017, 31(6):1201-1213 WANG Dapeng, YIN Jinyin, TIAN Naxin, et al. Division and resource evaluation of hydrocarbon plays in the Senegal Basin, West Africa [J]. Geoscience, 2017, 31(6): 1201-1213. |
[9] | Brun M V L Lucazeau F. Subsidence, extension and thermal history of the West African margin in Senegal [J]. Earth and Planetary Science Letters, 1988, 90: 204-220. doi: 10.1016/0012-821X(88)90101-X |
[10] | Lehner P, De Ruiter P A C. Structural history of Atlantic margin of Africa [J]. AAPG Bulletin, 1977, 61(7): 961-981. |
[11] | 郑应钊. 西非海岸盆地带油气地质特征与勘探潜力分析[D]. 中国地质大学(北京)博士论文, 2012. [ ZENG Yingzhao. Petroleum Geology Features and Exploration Potential Analysis in the Coastal Basins of West Africa[D]. A Dissertation Submitted to China University of Geosciences for Doctoral Degree, Beijng, 2012.] |
[12] | Davison I. Central Atlantic margin basins of North West Africa: Geology and hydrocarbon potential (Morocco to Guinea) [J]. Journal of African Earth Sciences, 2005, 43: 254-274. doi: 10.1016/j.jafrearsci.2005.07.018 |
[13] | Uchupi E, Emery K O, Bowin C O, et al. Continental Margin Off Western Africa: Senegal to Portugal [J]. AAPG Bulletin, 1976, 60(5): 809-878. |
[14] | 熊利平. 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 and Gas Geology, 2005, 26(5): 641-646. |
[15] | Ndiaye M, Ngom P M, Gorin G, et al. A new interpretation of the deep-part of Senegal-Mauritanian Basin in the Diourbel-Thies area by integrating seismic, magnetic, gravimetric and borehole data: Implication for petroleum exploration [J]. Journal of African Earth Sciences, 2016, 121: 330-341. doi: 10.1016/j.jafrearsci.2016.06.002 |
[16] | Watts A B, Stewart J. Gravity anomalies and segmentation of the continental margin offshore West Africa [J]. Earth and Planetary Science Letters, 1998, 156: 239-252. doi: 10.1016/S0012-821X(98)00018-1 |
[17] | Gouiza M, BertottiG, Hafid M, et al. Kinematic and thermal evolution of the Moroccan rifted continental margin: Doukkala‐High Atlas transect [J]. Tectonics, 2010, 29: TC5008. doi: 10.1029/2009TC002464 |
[18] | Lambiase J J. The framework of African rifting during the Phanerozoic [J]. Journal of African Earth Science, 1989, 8(2/3/4): 183-190. |
[19] | Seibold E. The Northwest African Continental Margin-An Introduction [J]. Geology of the Northwest African Continental Margin, 1982. doi: 10.1007/978-3-642-68409-8_1 |
[20] | Sebastian K, Russell B W, Aggeliki G. Large-scale mass wasting on the Northwest African Continental Margin: Some general implications for mass wasting on passive continental margins [C]// 5th International Symposium on Submarine Mass Movements and Their Consequences, Kyoto, Japan. 2011. |
[21] | Binks R M, Fairhead J D. A plate tectonic setting for Mesozoic rifts of west and central Africa [J]. Tectonophysics, 1992, 213: 141-151. doi: 10.1016/0040-1951(92)90255-5 |
[22] | Rene G, Jean-Christopheb M. Early Cretaceous rifts of western and central Africa—An overview [J]. Tectonophysics, 1992, 213: 153-168. doi: 10.1016/0040-1951(92)90256-6 |
[23] | Gerd W. Stratigraphy and structural features of the continental margin basin of Senegal and Mauritania [C]// in von Rad U, Hinz K, Sarnthein Met al, eds. Geology of the northwest African continental margin. Berlin Heidelberg, New York, Springer-Verlag, 1982: 160-181. |
[24] | Michard A, Saddiqi O, Chalouan A, et al. Continental Evolution: The Geology of Morocco. Lecture Notes in Earth Sciences 116[M]. Springer-Verlag Berlin Heidelberg, 2008. |
[25] | Mitchum R M, Vail P R, Sangree J B. Seismic stratigraphy and global changes of sea level [J]. Memoir-American Association of Petroleum Geologists, 1977, 26: 117-133. |
[26] | Scotese C R, Boucot A J, Mckerrow W S. Gondwanan palaeogeography and palaeoclimatology [J]. Journal of African Earth Sciences, 1999, 28(1): 99-114. doi: 10.1016/S0899-5362(98)00084-0 |
[27] | Mourlot Y, Roddaz M, Dera G, et al. Geochemical evidence for large-scale drainage reorganization in Northwest Africa during the Cretaceous [J]. Geochemistry Geophysics Geosystems, 2018. doi: 10.1029/2018GC007448. |
Geotectonic map showing regional geological units and the study area (modified from reference [3])
A stratigraphic section of the north sub-basin (see a-b in fig. 1 for location of the section, modified from references [9, 10])
Cretaceous seismic-logging section and geological interpretation (see c-d in Fig. 1 for section location)
Tectonic evolution of the study area (see e-f in Fig. 1 for section location)
Tectono-sedimentary evolution of the study area
Geomorphologic evolution characteristics of the shelf edge in the study area
Integrated stratigraphic column showing lithology, sea level fluctuation, tectono-sedimentary stage, and deep-sea fan types of the study area
RMS amplitude attribute and geological interpretation of Coniacian-Santonian
Distribution map of major faults and current rivers in Senegel Basin (fault data from reference [3])