The Pouni area is made up of basalts belonging to the Boromo belt, lamprophyres and granitoids. These geological formations are similar to geological formations of the same type in other regions of the Palaeoproterozoic domain of the Man/Leo shield. This study, which focused on the petrographic and geochemical characteristics of these geological formations, led to the following main conclusions: The lamprophyres are basic plutonic rocks that cut through other geological formations. The basalt belongs to the northern part of the Borormo belt and is thought to be a relic of overthickened oceanic plateaus. There are two groups of granitoid rocks. The granodiorite has a geochemical signature close to that of Archean TTGs and is metaluminous in character. It has a low potassium content. The minor element and rare earth element spectra indicate that it could be derived from partial melting of basic magmatic rocks. Biotite granites are peraluminous and highly potassic. Minor element contents and rare earth spectra indicate that they could be derived from partial melting of felsic materials. Geotectonic diagrams show that the granitoids identified in the Pouni zone were emplaced in an active tectonic context, similar to that of present-day subduction zones.
References
[1]
Castaing, C., Billa, M., Milési, J.P., Thiéblemont, D., Le Métour, J., Egal, E., Donzeau, M., Guerrot, C., Cocherie, A., Chèvremont, P., Tegyey, M., Itard, Y., Zida, B., Ouédraogo, I., Koté, S., Kaboré, B.E., Ouédraogo, C., Ki, J.C. and Zunino, C. (2003) Notice explicative de la carte géologique et minière du Burkina Faso à 1/1 000 000. Edit. B.R.G.M., Orléans, 147.
[2]
Tapsoba, B., Lo, C.-H., Jahna, B.-M., Chunga, S.-L., Wenmenga, U. and Iizuka, Y. (2013) Chemical and Sr-Nd Isotopic Compositions and Zircon U-Pb Ages of the Birimian Granitoids from NE Burkina Faso, West African Craton: Implications on the Geodynamic Setting and Crustal Evolution. Precambrian Research, 224, 364-396. https://doi.org/10.1016/j.precamres.2012.09.013
[3]
Tshibubudze, A., Hein, K.A.A. and McCuaig, T.C. (2015) The Relative and Absolute Chronology of Strato-Tectonic Events in the Gorom-Gorom Granitoid Terrane and Oudalan-Gorouol Belt, Northeast Burkina Faso. Journal of African Earth Sciences, 112, 382-418. https://doi.org/10.1016/j.jafrearsci.2015.04.008
[4]
Naba, S., Lompo, M., Débat, P., Bouchez, J.L. and Béziat, D. (2004) Structure and Emplacement Model for Late-Orogenic Paleoproterozoic Granitoids: The Tenkodogo-Yamba Elongate Pluton (Eastern Burkina Faso). Journal of African Earth Sciences, 38, 41-57. https://doi.org/10.1016/j.jafrearsci.2003.09.004
[5]
Vegas, N., Naba, S., Bouchez, J.L. and Jessell, M. (2008) Structure and Emplacement of Granite Plutons in the Paleoproterozoic Crust of Eastern Burkina Faso: Rheological Implications. International Journal of Earth Sciences, 97, 1165-1180.
https://doi.org/10.1007/s00531-007-0205-z
[6]
Ilboudo, H., Sawadogo, S., Kagambega, N. and Remmal, R. (2021) Petrology, Geochemistry, and Source of the Emplacement Model of the Paleoproterozoic Tiébélé Granite Pluton, Burkina Faso (Wes-Africa): Contribution to Mineral Exploration. International Journal of Earth Sciences, 110, 1753-1781.
https://doi.org/10.1007/s00531-021-02039-3
[7]
Doumbia, S., Pouclet, A., Kouamelan, A., Peucat, J.J., Vidal, M. and Delor, C. (1998) Petrogenesis of Juvenile-Type Birimian (Paleoproterozoic) Granitoids in Central Cote-d’Ivoire, West Africa: Geochemistry and Geochronology. Precambrian Research, 87, 33-63. https://doi.org/10.1016/S0301-9268(97)00201-5
[8]
Lompo, M. (2009) Geodynamic Evolution of the 2.25-2.0 Ga Palaeoproterozoic Magmatic Rocks in the Man/Leo Shield of the West African Craton. A Model of Subsidence of an Oceanic Plateau. In: Reddy, S.M., Mazumder, R., Evans, D.A.D. and Collins, A.S., Eds., Palaeoproterozoic Supercontinents and Global Evolution, Geological Society, London, Special Publication 323, 231-254.
https://doi.org/10.1144/SP323.11
[9]
Baratoux, L., Metelka, V., Naba, S., Jessell, M.W., Grégoire, M. and Ganne, J. (2011) Juvenile Paleoproterozoic Crust Evolution during the Eburnean Orogeny (~2.2-2.0 Ga), Western Burkina-Faso. Precambrian Research, 191, 18-45.
https://doi.org/10.1016/j.precamres.2011.08.010
[10]
Ouiya, P., Yaméogo, A.O., Ilboudo, H. and Naba, S. (2022) Implication of Paleoproterozoic Basalt Fertility Related to Mantle Plume Activity in Nassara Gold Mineralization (Burkina Faso, West Africa). Open Journal of Geology, 12, 1013-1031.
https://doi.org/10.4236/ojg.2022.1211048
[11]
Jenen, L.S. (1976) A New Cation Plot for Classifying Sub-Alkaline Volcanic Rocks. Ontario Division Mines Miscellaneous Paper No. 66.
[12]
Augustin, J. and Gaboury, D. (2017) Paleoproterozoic Plume-Related Basaltic Rocks in the Mana Gold District in Western Burkina Faso, West Africa: Implications for Exploration and the Source of Gold in Orogenic Deposits. Journal of African Earth Sciences, 129, 17-30. https://doi.org/10.1016/j.jafrearsci.2016.12.007
[13]
Barrett, T.J. and MacLean, W.H. (1999) Volcanic Sequences, Lithogeochemistry, and Hydrothermal Alteration in Some Bimodal Volcanic-Associated Massive Sulfide Systems. In: Barrie, C.T. and Hannington, M.D., Eds., Volcanics-Associated Massive Sulfide Deposits: Processes and Examples in Modern and Ancient Settings, GeoScienceWorld, Alexandria, 105-133.
[14]
Condie, K.C. (1999) Mafic Crustal Xenoliths and the Origin of the Lower Continental Crust. Lithos, 46, 95-101. https://doi.org/10.1016/S0024-4937(98)00056-5
[15]
Peccerillo, A. and Taylor, S.R. (1976) Geochemistry of Eocene Talc-Alkaline Volcanic Rocks from the Kastamonu Area, Northern Turkey. Contributions Mineralogy Petrology, 58, 63-81. https://doi.org/10.1007/BF00384745
[16]
Harker, A. (1909) The Natural History of Igneous Rocks. Methuen and Co., London, and Macmillan, New York, 377 p.
[17]
Sun, S.S. and McDonough, W.F. (1989) Chemical and Isotopic Systematics of Oceanic Basalts: Implications for Mantle Composition and Processes. In: Sanders, A.D. and Norry, M.J., Eds., Magmatism in the Ocean Basins, Vol. 42, Geological Society Special Publication, London, 313-345. https://doi.org/10.1144/GSL.SP.1989.042.01.19
[18]
Pearce, J.A., Harris, N.B.W. and Tindle, A.G. (1984) Trace Element Discrimination Diagrams for the Tectonic Interpretation of Granitic Rocks. Journal of Petrology, 25, 956-983. https://doi.org/10.1093/petrology/25.4.956
[19]
Pearce, J.A. (2008) Geochemical Fingerprinting of Oceanic Basalts with Applications to Ophiolite Classification and the Search for Archean Oceanic Crust. Lithos, 100, 14-48. https://doi.org/10.1016/j.lithos.2007.06.016
[20]
Ouiya, P., Yaméogo, A.O., Sawadogo, S. and Naba, S. (2023) Lamprophyre Rocks in the Nassara Gold Deposit, Southwest Burkina Faso: Characteristics and Implication for Mining Exploration. Open Journal of Geology, 13, 1291-1311.
https://doi.org/10.4236/ojg.2023.1312056
[21]
Yaméogo, A.O., Naba, S. and Traoré, S.A. (2020) Caractères pétrographiques et géochimiques des granitoides de la région de Dori au nord-est du Burkina Faso, Craton Ouest Africain. Afrique Science, 16, 375-395.
[22]
Block, S., Baratoux, L., Zeh, A., Laurent, O., Bruguier, O., Jessell, M.W., Ailleres, L., Sagna, R., Parra-Avila, L.A. and Bosch, D. (2016) Paleoproterozoic Juvenile Crust Formation and Stabilisation in the South-Eastern West African Craton (Ghana); New Insights from U-Pb-Hf Zircon Data and Geochemistry. Precambrian Research, 287, 1-30. https://doi.org/10.1016/j.precamres.2016.10.011
[23]
Pawlig, S., Gueye, M., Klischies, R., Schwarz, S., Wemmer, K. and Siegesmund, S. (2006) Geochemical and Sr-Nd Isotopic Data on the Birimian of the Kedougou-Kenieba Inlier (Eastern Senegal): Implications on the Paleoproterozoic Evolution of the West African Craton. South African Journal of Geology, 109, 411-427.
https://doi.org/10.2113/gssajg.109.3.411
[24]
Vidal, M., Gumiaux, C., Cagnard, F., et al. (2009) Evolution of a Paleoproterozoic “Weak Type” Orogeny in the West African Craton (Ivory Coast). Tectonophysics, 477, 145-159. https://doi.org/10.1016/j.tecto.2009.02.010
[25]
Lompo, M. (2010) Paleoproterozoic Structural Evolution of the Man-Leo Shield (West Africa). Key Structures for Vertical to Transcurrent Tectonics. Journal of African Earth Sciences, 58, 19-36. https://doi.org/10.1016/j.jafrearsci.2010.01.005
[26]
Yaméogo, A.O., Ouiya, P., Traoré, A.S., Sawadogo, S., Naba, S., Rousse, S. and Macouin, M. (2023) Rheological Context of Emplacement of the Dori, Gorom-Gorom and Touka Bayèl Granitic Plutons (Northeast Burkina Faso, West African Craton). Journal of African Earth Sciences, 208, Article ID: 105081.
https://doi.org/10.1016/j.jafrearsci.2023.105081
[27]
Abouchami, W., Boher, M., Michard, A. and Albarède, F. (1990) A Major 2.1 Ga Old Event of Mafic Magmatism in West Africa: An Early Stage of Crustal Accretion. Journal of Geophysical Research, 95, 17605-17629.
https://doi.org/10.1029/JB095iB11p17605
[28]
Boher, M., Abouchami, W., Michard, A., Albarède, F. and Arndt, T.N. (1992) Crustal Growth in West Africa at 2.1 Ga. Journal of Geophysical Research, 97, 345-369.
https://doi.org/10.1029/91JB01640
[29]
Liégeois, J.P., Claessens, W., Camara, D. and Klerkx, J. (1991) Short-Lived Eburnean Orogeny in Southern Mali. Geology, Tectonics, U-Pb and Rb-Sr Geochronology. Precambrian Research, 50, 111-136.
https://doi.org/10.1016/0301-9268(91)90050-K
[30]
Taylor, N.P., Moorbath, S., Leube, A. and Hirdes, W. (1992) Early Proterozoic Crustal Evolution in the Birimian of Ghana: Constraints from Geochronology and Isotope Geochemistry. Precambrian Research, 56, 97-111.
https://doi.org/10.1016/0301-9268(92)90086-4
[31]
Gasquet, D., Barbey, P., Adou, M. and Paquette, J.L. (2003) Structure, Sr-Nd Isotope Geochemistry and Zircon U-Pb Geochronology of the Granitoids of the Dabakala Area Cote d’Ivoire: Evidence for a 2.3 Ga Crustal Growth Event in the Palaeoproterozoic of West Africa. Precambrian Research, 127, 329-354.
https://doi.org/10.1016/S0301-9268(03)00209-2
[32]
Parra-Avila, L.A., Belousova, E., Fiorentini, M.L., Baratoux, L., Davis, J., Miller, J. and McCuaig, T.C. (2016) Crustal Evolution of the Paleoproterozoic Birimian Terranes of the Baoule-Mossi Domain, Southern West African Craton: U-Pb and Hf-Isotope Studies of Detrital Zircons. Precambrian Research, 274, 25-60.
https://doi.org/10.1016/j.precamres.2015.09.005
[33]
Eglinger, A., Thébaud, N., Zeh, A., Davis, J., Miller, J., Parra-Avila, L.A., Loucks, R., McCuaig, C. and Belousova, E. (2017) New Insights into the Crustal Growth of the Paleoproterozoic Margin of the 185 Archean Kemena-Man Domain, West African Craton (Guinea): Implications for Gold Mineral System. Precambrian Research, 292, 258-289. https://doi.org/10.1016/j.precamres.2016.11.012
[34]
Mériaud, N., Thébaud, N., Masurel, Q., Hayman, P., Jessell, M., Kemp, A., Evans, N.J., Fisher, C.M. and Scott, P.M. (2020) Lithostratigraphic Evolution of the Bandamian Volcanic Cycle in Central Cote d’Ivoire: Insights into the Late Eburnean Magmatic Resurgence and Its Geodynamic Implications. Precambrian Research, 347, Article ID: 105847. https://doi.org/10.1016/j.precamres.2020.105847