Reconstitution Paléoenvironnementale des Formations Maastrichtiennes, Cénomaniennes et Albiennes Basée sur les Données Sédimentologiques et Ichnologiques Issues des Carottes du Puits FIM-1X dans le Bassin Sédimentaire Offshore de la Cote d’Ivoire - Fea, Isaac; Jonas, Able Guiako; Kamagate Djodjo, Maria; Assalé Fori Yao , Paul (European Scientific Journal, ESJ, 2022)
Les Ã©tudes sÃ©dimentologiques et ichnologiques dÃ©taillÃ©es du puits FIM-1X ont Ã©tÃ© effectuÃ©es. Les analyses physiques ont Ã©tÃ© rÃ©alisÃ©es sur les Ã©chantillons de carottes. L’objectif principal est de caractÃ©riser la diversitÃ© de faciÃ¨s rencontrÃ©s dans les formations maastrichtiennes, cÃ©nomaniennes et albiennes afin de dÃ©terminer les diffÃ©rents palÃ©oenvironnement rencontrÃ©s dans le puits FIM-1X du bassin offshore de CÃ´te dâ€™Ivoire. Les rÃ©sultats sÃ©dimentologiques indiquent que les successions lithologiques des Ã©chantillons de carottes comprennent quatre grands groupes de lithofaciÃ¨s : galets (PS), grÃ¨s propre (S), sable argileux (SM) et argile (HM, ML, MJ & M). Ces groupes de lithofaciÃ¨s ont ensuite Ã©tÃ© subdivisÃ©s en faciÃ¨s constitutifs basÃ©s principalement sur des structures sÃ©dimentaires. Le groupe des galets comprend uniquement les granules. Le groupe de grÃ¨s propre comprend trois faciÃ¨s : grÃ¨s massif, grÃ¨s laminÃ© et grÃ¨s Ã rides. Le groupe de sable argileux comprend deux faciÃ¨s Ã savoir les sables argileux laminÃ©s et dÃ©formÃ©s. Le groupe dâ€™argile comprend trois faciÃ¨s principaux, Ã savoir les structures hÃ©tÃ©rolithiques Ã dominance argileuses, les argiles calcareuses, et les argiles pures. Une diversitÃ© d’ichnofossiles a Ã©tÃ© identifiÃ©e dans les carottes, notamment : Ophiomorpha, Palaeophycus, Thalassinoides, Spyrophyton et Scolicia. Lâ€™intÃ©gration des donnÃ©es sÃ©dimentaires (faciÃ¨s de granules, grÃ¨s, sable argileux et argile) et des ichnofossiles reconnues a permis de caractÃ©riser des environnements de chenaux du front deltaÃ¯que, de complexe chenaux â€“ levÃ©es et de milieux marins cÃ´tiers (Shoreface) dans ces formations carottÃ©s dâ€™Ã¢ge Maastrichtien, CÃ©nomanien at Albiens. Ces conditions d’environnements bien prÃ©servÃ©s pourraient constituer de possibles bons rÃ©servoirs d’hydrocarbures. Detailed sedimentological and ichnological studies of FIM-1X well were performed. Physical analyses were carried out on the core samples. The main target is to characterize the diversity of facies encountered in the Maastrichtian, Cenomanian and Albian formations in order to determine the different paleoenvironments encountered in the FIM-1X well of the CÃ´te d’Ivoire offshore basin. The sedimentological results indicate that the lithological successions of the core samples include four major groups of lithofacies: pebbles (PS), clean sandstone (S), muddy sandstone (SM) and mudstone (HM, ML, MJ & M). These lithofacies groups were then subdivided into constituent facies based mainly on sedimentary structures. The group of pebbles includes only the granules. The clean sandstone group includes three facies: massive sandstone, laminated sandstone and ripple sandstone. The muddy sandstone group includes two facies namely the laminated and deformed muddy sandstone. The mudstone group includes three main facies, namely heterolithic structures predominantly mudstone, calcareous mudstone, and pure mudstone. A variety of ichnofossils have been identified in cores, including: Ophiomorpha, Palaeophycus, Thalassinoides, Spyrophyton and Scolicia. The integration of sedimentary data (granule, sandstone, muddy sandstone and mudstone facies) and recognized ichnofossils made it possible to characterize the environments of delta front channels, complex channels - levees and shallow marine environments (Shoreface) in these Maastrichtian, Cenomanian and Albian formations. These well preserved environments conditions could be a possible good hydrocarbon reservoirs.