Geochemistry, Depositional Environment, and Economic Potential of the Toto-Muro Banded Iron Formation, North-Central Nigeria

Abstract

The Toto-Muro Banded Iron Formation (BIF) in north-central Nigeria is a Precambrian
iron deposit whose geochemical characteristics provide insights into its genesis,
depositional environment, and economic significance. Major and trace element
geochemistry, including Fe₂O₃, SiO₂, and Al₂O₃ concentrations, indicate a dominant
hydrothermal origin with minimal detrital input, as confirmed by MnO/TiO₂ vs.
Fe₂O₃/TiO₂ and Fe-Mn-Al ternary plots. Rare earth element (REE) patterns exhibit
light REE (LREE) enrichment, weak to moderate Eu anomalies, and Y/Ho ratios ranging
from 3.5 to 51, suggesting a mixed hydrothermal-seawater depositional environment.
The presence of negative Eu anomalies in some samples reflects increasing atmospheric
oxygenation during the Paleoproterozoic (Planavsky et al., 2012). Tectonically, the
deposit is consistent with passive margin to back-arc basin settings, similar to other
West African BIFs. Comparisons with BIFs in Cameroon highlight variations in detrital
input and tectonic evolution.Economically, the high Fe₂O₃ content and low
concentrations of deleterious elements (Ti, Al, and P) indicate potential for direct
shipping ore (DSO) suitability, enhancing its viability for iron and steel industries. This
study provides critical insights into the geodynamic evolution of the region and
underscores the economic importance of the Toto-Muro BIF in Nigeria’s mineral
resource sector.