Geochemical Properties of Kalambaina Formation: Implication on Limestone and Marlstone Qualities for Industrial Uses, Sokoto Basin, Nigeria

Abstract

Six samples were collected from Bua Cement Quarry site of Kalambaina Formation with a view towards determining the geochemical properties of the lithofacies, the industrial qualities and applications of the limestone and marlstone. Field outcrop litho-log description was carried out by noting the composition, textural attributes, fossil content, structures and diagenetic effect. The samples were subjected to geochemical analysis using atomic absorption spectrometry (AAS). Field result shows that Kalambaina sequence varies at the base from sparsely fossiliferous whitish limestone, overlain by light grey fissile shale, subsequently overlain by poorly fossiliferous limestone. The shale is intercalated within the upper and lower limestone beds. The non-fossiliferous limestone is unconformably overlain by sandstone, marlstone and micaceous shale which is unconformably capped by conglomeratic ironstone. The geochemical results that for the clastic facies (sandstone and shale) have SiO₂, CaO, and Al₂O₃ average concentration values of 66.7, 24.43 and 0.03 % respectively. Carbonate sediments have average concentration values in SiO₂, CaO and Al₂O₃ with 1.26, 52.36 and 0.56 % respectively, which implies that the carbonate were marine sourced while the clastic sediments were continentally derived. The CaO and SiO₂ values for the limestone (52.36, 1.27 %), and marlstone (50.10, 1.26 %) are at variance due to influx of clastic material into the marine carbonate. A comparison of the Kalambaina carbonate rocks with other deposits in Nigeria shows higher CaO content and lower SiO₂ value except Shagamu Limestone (CaO: 59.20 % and SiO₂: 5.70 %) with higher concentration values. The kalambaina Limestone has a moderately high CaO value of 54.61 % and low SiO₂ content of 1.26 % which make it suitable for cement production, and other industrial purposes.