BIOZONATION AND AGE RECONSTRUCTION OF 4000FT TO 4540FT SECTION OF WELL-X, NIGER DELTA, NIGERIA

Abstract

Biozonation and Age reconstruction of an offshore Well-X in the Niger Delta was carried out using10composite ditch cutting samples, Palynological studies was carried out on the samples to determine the age of the formation penetrated in the well, generate a range chart for the palynomorphs and generate biozones. The samples were described and prepared using the standard non mineral acid method of preparing Palynological samples. The interval studied was between 1219m (4000ft) -1384m (4540ft) thickness, belonging to the Agbada Formation which is of late Miocene. Lithologically the section penetrated by the well varies from sandstone bed to shaly bed. One biozone of the SPDC scheme P850 has been erected. The P850 zone palynomorphs observed within this interval which coincides with the P860 subzone include abundance of Zonocostitesramonae, rich occurrence of Stereisporitessp, Retibrevitricolporites obodoensis, and Psilatricolporites crassus, scanty Nympheapollislotus, and Multiareolites formosus as well as the presence of Peregrinipollis nigericus. The age of the sediment is of the late Miocene.

Keywords

• palynology
• biozonation
• range chart
• palynomorphs
• late miocene