FORAMINIFERAL BIOSTRATIGRAPHY AND PALAEOENVIRONMENTAL INTERPRETATION OF WELL – 004 (OML – 34) CENTRAL

Abstract

A total of seventy – two ditch cutting samples from well – 004 in OML – 34 onshore Niger Delta
were described and analyzed for their foraminiferal content. Lithologic description of the
samples shows that the entire sediments belong to the paralic sequence of Agbada Formation. A
total of sixty three foraminiferal species were recovered out of which forty – five were
benthonics and eighteen are planktonics. The planktonic foraminifera index species recovered
from the well revealed that the sediments penetrated in the well range in age from Late
Oligocene to Early Middle Miocene. Five planktonic foraminiferal zones namely Globigerina
ciperoensis - Globorotalia opima nana Interval zone, Globigerina ciperoensis - Globigerinoides
altiaperturus Interval zone, Globigerinoides altiaperturus – Catapsydrax dissimilis Interval zone,
Catapsydrax dissimilis - Catapsydrax stainforthi Interval zone and Catapsydrax stainforthi -
Praeorbulina sicana Interval zone have been identified based on First Downhole Occurrences and
Last Downhole Occurrences of the planktonic foraminiferal index forms. Based on the triangular
plot of the wall composition of the foraminiferal suborders the sediments in the study well are
considered to be of normal salinity depositional environment deposited in dysoxic to oxic
condition. Paleobathymetric ranges of some selected benthic foraminifera species shows that the
palaeobathymetry of the studied well section ranges from non-marine to outer neritic.