Foraminiferal Biostratigraphy Studies Of Agbara 17 Well Niger Delta Basin Nigeria

Abstarct The biostratigraphy of Agbara A-17 well which penetrated the Tertiary sediments of the Niger Delta well was studied. Stratigraphical and taxonomic studies are made of the arenaceous and calcareous benthonics as well as planktonic foraminifera of the middle Miocene to Pleistocene strata of southern Niger Delta. Benthonic foraminifera appeared to control about 58.45 percent and planktonic foraminifera control about 41.55 percent of the total fauna counts. Fourty genera comprising fourty five species have been identified from eighty five bore hole samples. The species are composed of calcareous benthons which are typified by the Buliminids. Amphistigerinids Rotalids Anomalinids Alveolinellids and lituoloids. The calcareous are typified by Globigerinids and Globorotalids.The arenaceous are typified by Urnula Artica. The interval studied is assigned a Middle Miocene to Pleistocene age based on the presence of Orbulina universa dorbigny. The abrupt break in the span of both benthonic and planktonic foraminifera in the upper part of the well also marks the PliocenePleistocene boundary. The fossil assemblages suggest that the strata containing them were deposited in littoral through neritic environment in an area that was periodically exposed to the sea as evidenced by the foraminifera fauna assemblage. The paleo environment of deposition of sediments in the Agbara-A17 well was shallow through neritic as indicated by benthonic and planktonic foraminiferas.