Geology and Gold Mineralization around Kutcheri, northwestern Nigeria

Abstract

The study area predominantly consists of metasediments, porphyritic granites with minor amphibolite dykes, quartz vein and quartzofeldspathic intrusions. The metasediments are fractured and folded in places. The dominant fold axes and quartz vein intrusions trend NNE-SSW parallel to the regional foliation of the rocks. Artisanal mining of placer gold mineralization were documented around the banks of Rivers in northwestern part of the study area. Panning of 40kg sediments from pits in the area around Gidan Boss and Dutsen Burka yields 0.28g Au. Grain morphology shows both eluvial and alluvial deposits occur. The eluvial gold are presumed to occur within steeply dipping (70° E and above) quartz veins. Geochemical analysis of 13 quartz vein samples to characterize samples enriched with target (Au) and some pathfinder elements (Pb, Hg, Cu, Ag and Zn) above background levels were carried out. The concentration in ppm had Au (< 1-4.8) and others, Pb (<1-28), Hg (<0.5), Cu (6.2 to 61.4), Ag (<0.5) and Zn (8.8 to 39). There is no significant difference between concentration of analytes in Dutsen Burka and Gidan Boss at α = 0.05. Also, strong positive correlation between Au and Cu, Au and Pb confirms they are indicator elements for Au in the area.