TITLE:
Li-Sn and Pb-Zn Type Mineralization in the Birimian Greenstone Belt of Banfora. Recommendations for the Exploration of Strategic and Base Metals, Burkina Faso, West Africa
AUTHORS:
Abdoulaye Ouédraogo, Kafohé Azise Héma, Mamadou Nimi, Seta Naba, Urbain Wenmenga
KEYWORDS:
Banfora, Belt, Exploration, Geochemistry, Anomaly, Mineralization
JOURNAL NAME:
International Journal of Geosciences,
Vol.16 No.10,
October
30,
2025
ABSTRACT: Regional exploration of base and strategic metals (Li, Nb, Ta, Sn) in the Kangounadéni sector, part of the Banfora Belt (Paleoproterozoic greenstone belt, West African Craton), was conducted using stream sediment and soil sampling around the two-micas leucogranite of Ferkessédougou. In this study, a total of 281 stream sediment samples and 640 soil samples from the Kangounadéni sector were analyzed to determine the concentrations of 57 major and trace elements, by the multi-acid digestion followed by the ICP-MS multi-element analysis. We processed geochemical analysis results using multivariate statistical techniques including principal component analysis and hierarchical classification, to identify geochemical trends and anomalous zones. Geochemical enrichment in K, Rb, U, and Nb is primarily related to the Ferkessédougou two-micas leucogranite, whereas enrichment in As, Sb, light rare earth elements (LREE), and medium to high contents of Fe, Ni, Cr, and Sc is characteristic of the volcanosedimentary formations. Two types of anomalies have been identified: (i) Li ± Sn anomalies within and around the two-micas Ferkessédougou leucogranite (Li up to 133 ppm in stream sediments and 194 ppm in soils, Sn up to 2.9 ppm in stream sediments and 19.2 ppm in soils), accompanied with high content in Na, K, and Rb in the granite. (ii) Pb-Zn outlying concentrations on its eastern edge, likely associated with meta-volcanosedimentary units (Pb up to 17.24 ppm in stream sediments and 523 ppm in soils, Zn up to 523 ppm in soils). Background thresholds in soils were determined for Li, Pb, Sn, W, Ta, and U at 120 ppm, 109 ppm, 4.1 ppm, 2.3 ppm, 6.6 ppm, and 9.1 ppm, respectively. The Li ± Sn anomalies align with a petrogenetic LCT granite/pegmatite source, related to the two-micas Ferkessédougou leucogranite. However, Nb and Ta concentrations in soils are low, making them unreliable indicators of mineralized zones. Additionally, the Pb-Zn anomaly suggests base metal enrichment linked to a potential sulfide mineralization process within the surrounding volcano-sedimentary rocks. The behavior of HFSE (W, Ti, Nb, Ta) and U is probably controlled by accumulation of residual minerals or laterization.