Airborne electromagnetic signature of a paleochannel uranium deposit

Abstract

Yellow Ltd., has been actively exploring four exclusive prospecting licenses (EPLs) in Namibia since 2007. Prior exploration of this area in the 1970?s and 80?s resulted in the discovery of extensive Tertiary uranium mineralization hosted by paleochannels. Detailed airborne radiometric data acquired in 2007 shows good correlation with known surficial mineralization, but provides no depth information about the known channels, and does not identify potential buried channels. In 2008, Aeroquest Surveys completed an AeroTEM helicopter time domain electromagnetic (HTEM) survey over the four EPLs. The electromagnetic (EM) data proved to be an excellent tool for mapping the conductive material associated with both near-surface and buried paleochannels. There is generally good correlation between the stronger AeroTEM responses and the known mineralization. The HTEM data were inverted using a 1- D layered earth algorithm to model the distribution of conductivity laterally and with depth. The modeled data effectively describe the lateral extent, thickness and relative conductivity of the paleochannels and have been found to be very useful in directing the ongoing drill program both for the delineation of known paleochannels and for the drilling of previously unknown paleochannels. Successful trenching and drill results from the Tubas-Oryx-Tumas paleochannel system clearly illustrate the important role that the HTEM data has played in the ongoing exploration on this project.