Marine Origin Of Nigerian Brines – A Contribution From Recent Trace Element Study

Abstract

Trace element analyses which employ the X – ray fluorescence (XRF) and pelletisation have been carried out on 17 salt samples extracted from Nigerian brines. Results of the analyses reveal that these samples, from the Albian – Turonian formations in the middle Benue and Anambra basins, have Sr values of between 148ppm and Ba values of between 105 ppm and 135 ppm. Enhanced values of Ni (9ppm), Co (4ppm), and Cu (35ppm), indicate close association with carbonate rocks from the area. Such carbonates were deposited during marine maxima. Co, Ni and Cu enrichment in the brines possibly resulted from marine scavenging at the ocean floor occasioned by Albian – Turonian marine effects. These marine effects on the middle Benue and Anambra basins and the tectonic activities of the area provided optimum marine conditions for Co, Cu and Ni enrichment. Similarity in geology and structures in the brine fields correlate well with similar NaCl contents in the salts extracted from the brines. Absence of rock salt in these fields, similar geology and chemistry of the salt samples from the brines point to a common marine source. KEY WORDS: Marine, Scavengers, Glauconite, Albian, Turonian. Global Journal of Geological Sciences Vol.3(1) 2005: 1-8