The southern Mid-Niger Basin also known as the Lokoja Sub-Basin in central Nigeria forms part of the larger Bida or Mid-Niger Basin. An integrated sedimentologic and palynostratigraphic analysis of some exposed Cretaceous outcrops in the southern Mid-Niger Basin was carried out to ascertain the age, palynostratigraphy, and possible environment of deposition of this part of the basin. The Lokoja, Patti, and Agbaja Formations are the mappable lithological units found in this part of the basin. Sedimentologic analysis of the Lokoja Formation from the result of the computed grain size parameters shows a moderately to poorly sorted, symmetrical to negatively skewed, and platykurtic. Depositional environment inferred using skewness, standard deviation, median, and mean values gotten from the sedimentologic analysis shows the environment as of fluvial domain. Palynomorphs which are predominantly Maastrichtian comprises Cyathidites minor, Foveotriletes margaritae, Monocolpites marginatus, Longapertites marginatus, Cingulatisporites ornatus .Ephedripites sp., Echitriporites trianguliformis, Distaverrusporites simplex. Zlivisporites blanensis, Proteacidites longispinosu, Botryococcus braunii, and host of others were observed in different beds sampled in the basin and points at continental to marshy-swampy environment of deposition.
Key words: Sedimentology, palynostratigraphy, Maastrichtian, Lokoja Formation, Patti Formation, Mid-Niger Basin.
Key words: Key words: Sedimentology, palynostratigraphy, Maastrichtian, Lokoja Formation, Patti Formation, Mid-Niger Basin.
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