Palynological zonation and paleoclimatic condition of the sediments penetrated by Ash-3 well in the greater Ughelli Depobelt, Niger Delta Basin

Abstract

Palynological zonation and paleoclimatic condition of the sediments penetrated by Ash-3 Well in the Greater Ughelli Depobelt, Niger Delta was carried out in order to determine the palynological biozonation, age and the paleoclimatic condition the sediments were formed. The palynological analysis was carried out on seventy (70) ditch cutting samples at different intervals between 15ft to 11,430ft which allowed the recovery of one thousand, three hundred and twelve (1312) palynomorphs that includes one thousand, one hundred and fifty (1150) miospores, eleven (11) dinocysts and one hundred and fifty one (151) ancillary microfossils. Five (5) palynological zones were established using palynological characteristic of the age diagnostic index markers. The palynological zones established were the lumped P650-P670, lumped P620-P630, P580, P560 and P540 Zones. The age of the sediments penetrated by the well using the age diagnostic markers range from Oligocene to Early Miocene epoch. Based on the dominance of Zonocostites ramonae over Monoporites annnulatus, it showed that the sediments were deposited in a predominantly humid climate, cooler and wetter climatic condition.

Keywords: biozonation, depobelt, paleoclimatic, Agbada, diagnostic index markers