georefid:2000-002392SEDIS Publication Catalogue

ana.macario@awi.de

http://sedis.iodp.org/pub-catalogue/informationpointOfContact2011-06-23T00:00:00Zhttp://sedis.iodp.org/pub-catalogue/index.php?id=2000-0023921999-01-01publicationgeorefid:2000-002392Holbourn, AnnNatural History Museum Department of Palaeontology, London, United KingdomauthorKuhnt, WolfgangLacustrine Basin Research, United KingdomauthorEl Albani, AbderrazzakTechnical Outsourcing, United KingdomauthorPletsch, ThomasChristian-Albrechts-Universitaet zu Kiel, Federal Republic of GermanyauthorLuderer, FlorianUniversitaet Bremen, Federal Republic of GermanyauthorWagner, ThomasauthorGeological Society of London, London, United KingdompublisherdocumentHardcopyIn: Cameron, Nick R. (editor), Bate, Raymond H. (editor), Clure, Val S. (editor), The oil and gas habitats of the South Atlantic153195-222Upper Cretaceous benthonic foraminiferal assemblages, clay minerals, kerogen types and carbonate microfacies are examined in organic-rich sediments from western African coastal basins along a latitudinal transect extending from southern Morocco to Nigeria. Samples from onshore sections of the Tarfaya Basin, southern Morocco, from DSDP Site 369, from offshore commercial wells on the Casamance Shelf, Senegal, from DSDP Site 367, from ODP Site 959 and from onshore sections of the Benue Trough in Nigeria, are analysed. Organic-rich sediments from these sites are characterized by smectite-rich clay mineral assemblages, high amounts of marine organic matter and a typical benthonic foraminiferal biofacies dominated by buliminids and bolivinids. Benthonic foraminifera provide robust proxy indicators of palaeoproductivity and organic matter flux to the seafloor. The palaeobiogeographic distribution of benthonic foraminiferal biofacies can be used to identify areas and stratigraphic intervals of hydrocarbon accumulation. Lower Turonian benthonic foraminiferal assemblages exhibit extremely low diversity and are strongly dominated by a Gabonita biofacies, in contrast to Coniacian to Maastrichtian assemblages, which display higher diversity and contain numerous species of Buliminella, Praebulimina, Afrobolivinc, Bolivina and Orthokarstenia. The palaeobathymetric distribution of these high productivity benthonic foraminiferal biofacies reflects the establishment of a productivity driven oxygen minimum zone along the western African shelf, associated with an upwelling system active off coastal Africa during most of the Late Cretaceous. The extent of the high productivity equatorial belt appears to have shifted latitudinally during the Late Cretaceous as sea level and circulation patterns changed. The zone of highest productivity was broadest in the Early Turonian, when it coincided with the maximum sea-level rise and highest atmospheric temperature in the Late Cretaceous.completedEconomic geology, geology of energy sourcesStratigraphyAfricaassemblagesAtlantic Oceanbenthic taxaBenue ValleybiofaciesCampaniancarboncarbon dioxideclay mineralogyCretaceousDeep Sea Drilling ProjectDSDP Site 367DSDP Site 369Equatorial AtlanticForaminiferaGhanaIGCPInvertebrataIvory CoastkerogenLeg 159Leg 41MesozoicmicrofaciesmicrofossilsMoroccoNigeriaNorth AfricaOcean Drilling ProgramODP Site 959offshoreorganic carbonorganic compoundspaleoenvironmentpaleogeographypaleotemperaturepetroleumpetroleum accumulationproductivityProtistareconstructionsea-level changesSebkha TahSenegalSenonianspecies diversityTarfaya Basintotal organic carbontransgressionTuronianUpper CretaceousWest Africaurn:org.iodp:exp:159urnlargerWorkCitationcampaignurn:org.iodp:exp:41urnlargerWorkCitationcampaignurn:org.iodp:exp:41:site:367urnlargerWorkCitationstudyurn:org.iodp:exp:41urnlargerWorkCitationcampaignurn:org.iodp:exp:41:site:369urnlargerWorkCitationstudyurn:org.iodp:exp:41urnlargerWorkCitationcampaignurn:org.iodp:exp:159:site:959urnlargerWorkCitationstudyurn:org.iodp:exp:159urnlargerWorkCitationcampaignEnglishgeoscientificInformation-20.0250-2.44083.374026.3533IGCP Project No. 381