Devonian Miospores from Atiavi-1 Well in the Keta Basin, Southeastern Ghana

摘要

Miospore assemblages from the Atiavi-1 well in the Keta basin have been described to corroborate the upper Lower Devonian (Emsian) to lower Upper Devonian (Frasnian) age assigned to the lower section of the well based on chitinozoan and acritacrch assemblage by Anan-Yorke (1974). The study also assigns Uppermost Devonian (Strunian) age to the upper part of well with a diverse, well preserved and abundant assemblage of pteridophytic spores and phytoclasts which hitherto has not been dated. Observations from palynomorph distribution reflect a change from marine environment of deposition for the lower section to that of fluvio-deltaic or nearshore environment for the upper part in a humid climate. The palynomorophs are well preserved and thermal maturity is within the oil floor and wet-gas zone.