Savanna Journal of Basic and Applied Sciences 2(1):66-73
Biostratigraphy and Paleoenvironment of Amansiodo-1 well, Anambra Basin, Nigeria
Kovona M. T., Obiosio E.O., Najime T., Hamidu I., Nwaejije E.C.
ABSTRACT
Lithostratigraphic and biostratigraphic analyses were carried out on ditch cuttings samples from Amansiodo-1 well, Anambra
Basin Nigeria. The lithostratigraphic description revealed the lithologies to be mainly shales, sandstones, clays, mudstones coal
and siltstone. Biostratigraphic analysis shows a total of thirty benthonic foraminifera species recovered (twenty-six arenaceous
and four calcareous) as a result three benthonic foraminiferal zones Ammobaculites amabensis/Miliammina pindigensis
concurrent range zone, Haplophragmoides saheliense interval zone and Haplophragmoides talokaense interval zone was
proposed for the well. The study also revealed shallow marine depositional environment based on the triangular plot of
foraminifera suborders, paleobathymetric and paleo-oxygenation studies suggested the studied portion of the well belong to
the Mamu Formation in the Anambra Basin. The well sediments are dated Maastrichtian based on the presence of
Haplophragmoides saheliense an index fossil for Campanian –Maastrichtian.
