Enhancing Stream Sediment Geochemical Anomalies Using Spatial Imaging: Case Study from Dagbala and Its Environs

Abstract

The exploration for solid minerals is a very demanding and costly operation and exploration techniques are continually modified, with the better data interpretation approach continuously sought after by operators of the solid mineral industry, so as to improve the success rate of mineral deposit discovery. Spatial imaging approach to interpretation of anomalies related to stream sediment geochemical data is increasingly being recognized, as a significant component of the geochemical survey data analysis in the prospect for concealed mineral deposits. It is apparent that the spatial rendering of such data enhances the interpretation of associated anomalies. The present study, therefore, adopts this technique to investigate the regional distribution of five chemical elements (Au, Zn, Pb, Cu, and Ag) in stream sediments derived predominantly from Precambrian Basement rocks in the Dagbala area. Stream sediment samples were analyzed for these elements in bulk fractions with an Atomic Absorption Spectrophotometer after hot extraction with aqua regia. In order to improve the spatial mapping of geochemical anomalies, the computed statistical threshold for the chemical data is used to augment geochemical models developed with Surfera contouring and 3-D surface mapping package. Stream sediment concentration data are extrapolated or interpolated at the sample points on stream beds, allowing geochemical anomalies to be aptly extracted for optimal spatial assessment. Geochemical models show anomalies of Ag, Cu, Au, and Zn, while grid vector maps depict the dispersion trend of the elements studied.