Distribution pattern of REE and other elements in the host rocks of the Gubrunde uranium occurrence,NE Nigeria

Prospecting for high grade uranium deposits in NE Nigeria has over the years among other reasons been handicapped by lack of adequate understanding of the elemental primary dispersion pattern associated with known occurrences in this region. Thirty six samples from a low grade uranium occurrence at Gubrunde consisting of disseminated ores and hostrocks were therefore analyzed for 38 elements by NAA, DNAA, EDXRF and flame AAS techniques. The analytical data were evaluated using multivariate statistical techniques. The results show three element groupings (associations). The first group consists of Pb, Ba, Ce, Sm (LREE), that are enriched with increasing uranium concentration in the mineralized zone and are therefore capable of serving as pathfinder elements for uranium. The second group comprising of MgO, K₂O, CaO, Na₂O and the HREE are depleted in the mineralized zone due to action of hydrothermal fluids and are indicative of altered/mineralized rocks. The third group consists of the rest bulk of elements which feature little or no significant enrichment with increasing uranium but associate with ferruginization (haematite) and possibly refractory minerals.