Foraminiferal Stratigraphy and Paleoecological Interpretation of Sediments Penetrated by Kolmani River -1 Well, Gongola Basin, Nigeria

Foraminiferal investigation of the Kolmani River -1 well yielded a total of forty two (42) species. The foraminiferal assemblages comprise 86% arenaceous benthonics, 4% calcareous benthonics and 8% planktonic foraminifera. Few ostracod and gastropods shells were recovered and they make up the remain...

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Format: Text
Language:English
Published: Science and Education Publishing 2014
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Online Access:http://pubs.sciepub.com/jgg/2/3/3
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Summary:Foraminiferal investigation of the Kolmani River -1 well yielded a total of forty two (42) species. The foraminiferal assemblages comprise 86% arenaceous benthonics, 4% calcareous benthonics and 8% planktonic foraminifera. Few ostracod and gastropods shells were recovered and they make up the remaining 2% of the assemblages. Quantitative and qualitative analyses of the recovered foraminifers were used to interpret the age, paleoecology, paleobathymetry and paleoenvironment of the sediments penetrated by the well. Three foramineferal assemblage zones consisting of Agathamina sp.2, Haplophragmoides bauchensis and Heterohelix moremani-Haplophragmoides talokensis Assemblage Zones were identified in the drilled interval of Kolmani River -1 Well. These zones are dated Campanian-early Santonian, early Coniacian-early Turonian and early Turonian-late Cenomanian respectively. The paleobathymetry ranges from Inner to Outer neritic suggesting water depths of less than 200 m. The overall depositional environments varies between coastal plain/estuarine to open marine setting. The dominance of agglutinated foraminiferal species such as Ammobaculites sp, Haplophragmoides sp, Miliammina sp and Trochamina sp suggest restricted, low oxygen bottom water conditions for most of the paleoenvironments.