CALCAREOUS BENTHIC FORAMINIFERA BIOSTRATIGRAPHY AND PALEOENVIRONMENT OF DEPOSITION OF KK-1 WELL, OFFSHORE WESTERN NIGER DELTA, NIGERIA
EDWARD A. OKOSUN *
Department of Geology, Federal University of Technology, Minna, Nigeria
JACINTA N. CHUKWUMA-ORJI
Department of Geology, Federal University of Technology, Minna, Nigeria
*Author to whom correspondence should be addressed.
Abstract
A high resolution and quantitative benthic foraminiferal biostratigraphic analysis was carried out on ditch cutting samples from KK-1 well from the offshore Niger Delta. The study was undertaken within the depth intervals of 15280 to 17670 feet with the aim of subdividing the sequence into calcareous benthic foraminiferal biozones and also determine the paleoenvironment of deposition. The standard technique for foraminiferal recovery was followed. Two hundred and thirteen benthic foraminiferal species were identified. The studied depth intervals were very rich in benthic foraminfera and they were moderate to well preserved. Using the age diagnostic species and assemblages, the benthic foraminifera zones established in this study are the interval range zones of: Eponides eshira – Valvulineria sp, Eponides berthelotianus – Epistominella vitrea, Planullaria auris - Buliminella multicamerate, Anomallinoides midwayensis – Lagena laevis and Uvigerina farinosa – Pullenia eocenica respectively. The age of the studied interval ranged from middle – late Eocene to middle Miocene. The paleoenvironment of the studied intervals ranged from the outer neritic to bathyal.
Keywords: Benthic foraminfera, biostratigraphy, paleobathymetry, KK-1 well, Niger Delta, Nigeria