Ancient Environment, Sedimentological Characteristics and Mechanism of Transport of Campanian - Maastritchian Sandstone, Lokoja Formation, Bida Basin, Nigeria

The Campanian - Maastritchian Sandstone, Lokoja Bassange Formation, Bida Basin, was studied to decipher its ancient environment, the mechanism of transport and the sedimentological characteristics of the sandstone. The results of grain size analysis show that the sandstone has medium-sized grains that are leptokurtic to extremely leptokurtic, moderately well-sorted to moderately sorted, and primarily near symmetrical to coarsely skew. The medium-grained sediments imply that grains have been transported over a considerable distance. The near symmetry of the sediments suggests that the processes of erosion and deposition are almost in equilibrium with one another. Leptokurtic grains predominate in the sandstone, indicating compositionally immature and a texturally mature sandstone. The coarse positive skewedness indicates a fluvial (non-beach) paleoenvironment origin. Also, the sorting of Ifon Sandstone at Uzebba and Ori-Ohin ranges from 0.54-1.26(0.90 average) and 0.62 to 1.42 (1.0 average), which are both of fluvial origin, after Folk’ environmental classification. The results from the environmental discrimination plots indicate an ancient fluvial depositional environment. The mechanism of transportation reveals that the sediments were moved and deposited by rolling, bottom suspension, and rolling, which are indicative of a high-energy, turbulent environment with high wave activity and tractive current deposits.