Geochemistry of Gold Deposits in Anka Schist Belt, Northwestern, Nigeria

Abstract

Gold quartz veins have been identified associated with the rock formations of the Anka Schist Belt forming eight gold deposits that include Kuba I, Kuba II, Doka, Dumi I, Dumi II, Zurzurfa I, Zurzurfa II, Jameson and Kwali. The present study involves the use of major and trace elements to characterize some of the features that are diagnostic of their setting and origin. The gold mineralization is characterized by average composition that plot within the sedimentary- metamorphic field of Na₂O/Al₂O₃ - K₂O/Al₂O₃ discrimination diagram, suggesting a metamorphic origin for the gold mineralizing fluids. Characterization of the inter-elemens ratios of the lithophile elements K, Rb, Ba. Rb, and Sr revealed that they are similar to those of average metasedimentary rocks; further suggesting mineralizing fluids of metamorphic origin. The result obtained is similar to what has been reported from Zuru, Birnin Gwari and Kushaka schist belts; and many other areas of gold mineralization in the country and the world. The study has also shown that favourable geochemical factors exist for the discovery of a Cu, Pb and Zn deposits in the study area, and that the old Zurzurfa mines may be as prospective for these base metals as they were for gold.