Foraminiferal Micropaleontology of Tertiary sediment in F-Well Niger Delta Basin were carried out
using foraminiferal biostratigraphy as geologic tools. Sedimentological description was carried out on 679 ditch cutting
samples which aided the erection of 103 lithozones. Fifty (50) ditch cutting samples was used with the aim of establishing
the Foraminiferal Biozones and age of the well. A total of eighty (80) foraminiferal species were recorded, most of the
species recorded are calcareous and arenaceous benthic foraminiferal species. They were about twenty-eight (28)
diagnostic foraminifera recognized. The evaluation of these foraminifera species enabled us to recognize the zones. The
foraminiferal abundances revealed two bio zones
N4-N3 Planktic zone and N3 – N2 Planktic zone which were suggested
based on index species among the recovered foraminiferal assemblages.
N4-N3 Planktic zone has a reference interval of
8,000ft – 9,400ft. The top of this zonal interval which ought to be marked by the FDO of
Ammonia becarril was
absent
but was estimated to be 8,000ft. The base of this zonal interval is marked by the LDO of
Epistominella vitriea
at 9,400ft.
Planktic zone N3 – N2 has a reference interval of 9,400ft – 10,000ft. The top of this interval is marked by the FDO of
Bolivina imperatrix
at 9,400 ft. The base of this interval is marked by the LDO of
Spirosplectamina wrightii
at 10,000 ft.
The studied intervals in the wells are dated Early Miocene - Oligoocene. Using the lithologic and foraminiferal studies, it
is inferred that the intervals penetrated by the well correspond to Agbada Formation.
