PARASEQUENCE SET ANALYSIS OF THE MAASTRICHTIAN TO PALEOCENE STRATIGRAPHIC SUCCESSION IN THE SOKOTO SECTOR OF IULLEMMEDEN BASIN, NORTHWESTERN NIGERIA

Abstract

ABSTRACT

Detailed geological field mapping of Maastrichtian - Paleocene sedimentary deposits exposed at the Sokoto sector of Iullemmeden Basin was carried out in this study. The principle of sequence stratigraphy was applied on the exposed outcrops for a better understanding of their depositional history. Results of the sequence stratigraphic analyses reveal three (3) parasequence types, Two (2) system tracts and one (1) condensed section. The parasequence of the lower and upper portion of Taloka and Wurno formations are made up of aggradational and progradational stacking patterns – which all belong to the Lowstand system tracts. Retrogradational stacking pattern was observed within the Dukamaje, Dange and Kalambaina formations which consist of fossiliferous limestone and shales. The retrogradational stacking pattern belongs to the Transgressive system tracts. The condensed section which was observed at the transitional boundary between Wurno and Dange formations near Gada village is represented by a 7 cm thick phosphate bed fused with glauconite and fossil bones. This indicate a strata associated with the maximum flooding surfaces, represented by sedimentary intervals deposited during the maximum marine transgression