New Approaches to Exploration Targeting in the Alligator Rivers

摘要

Uranium Equities (UEQ) has been exploring the Alligator Rivers Uranium Field (ARUF) since 2008. During this time it has targeted unconformity-style uranium deposits focused on the company's core landholding surrounding the historic, high-grade Nabarlek deposit (24 Mlbs at 1.84 per cent U_3O_8). The historic deposit has a small footprint (200 m long x 70 m down dip), with a shallow north plunge truncated by a dolerite sill, and the exploration prize at Nabarlek is to discover the down plunge extensions of the Nabarlek mine shoot beneath the Oenpelli Dolerite sill.While the prize has long been recognised, targeting a blind deposit beneath the sill (220 m true thickness) is a significant exploration problem. To target the shoot UEQ has re-examined lithogeochemical and spectral data from historical drilling and collected additional spectral data through the Northern Territory Geological Survey (NTGS) HyLogger, looking to characterise the alteration signature of the Nabarlek deposit, and track the Nabarlek shear and associated alteration halo beneath the sill.The new data sets can outline vectors to mineralisation within the broader alteration envelope, and critically these vectors have been identified in historic deep drilling below the sill, pointing to an untested position offset from the down plunge extensions of the historic mine.Using the knowledge gained from the historic mine, and by collating and collecting a similar database across the Project area, UEQ has identified a number of new, high-quality targets where alteration indicators suggest either a near-miss or the data provides a vector to new targets under post-mineral cover.The ARUF is a world-class mineral province, which, in addition to Nabarlek, hosts a number of large, high-grade deposits, including ERA's Ranger mine (194 Mlbs at 0.23 per cent U_3O_8) and Tabiluka deposit (312 Mlbs at 0.48 per cent U_3O_8). These high-value deposits were discovered in the 1960s and early 1970s through ground follow-up of regional airborne radiometric anomalies. Given the extent of post-mineral cover, new tools are required to generate the next cycle of discovery in this intensely mineralised province. UEQ has developed what it thinks are the next critical tools to lead to those discoveries.