Mount Swan Mag-Rad Survey Geophysics and Drilling Collaborations Program Regional-Scale Geophysics Round 17, 2025-2026 Mount Swan Exploration Licence EL 33877

Abstract

The Mount Swan mag-rad airborne survey covers most of EL 33877 which is located 185 km northeast of Alice Springs in flat country straddling the boundary of the northeastern margin of the Arunta Region Aileron Province and the Georgina Basin. Primary targets are REE's, energy metals and critical minerals. Dominant lithology is outcrop of Proterozoic metamorphics, sediments and granite in the southwestern half with onlap of Georgina Basin sediments to the northeast. Primary direction of outcrop and structures is WNW. The only known mineralisation in the region is small prospects of copper at Perenti, tungsten at Delnys and tantalite/lithium at Spotted Wonder. Only the latter is within the survey area. Limited historical drilling at the prospects has failed to provide results of interest. The airborne survey subject of the Collaborations Program was flown over 361 square kilometres on 100 metre north-south traverses for a total of 4,066 line kilometres. Existing data comprised regional NTGS surveys flown on 400 metre lines circa 25 years ago. The new survey has provided a superior dataset in terms of resolution and clarity in magnetics and radiometrics. The magnetic response over most of the area comprising gneisses and granites is complex. Two anomalies of amplitude up to 2,500 nT are evident over Un-named granite. Lack of outcrop and dated coarse published mapping provide no clues in respect of possible sources. A solid geology interpretation has been completed. It is proposed that a structural corridor evident as a magnetic low in the regional data is a shear zone occupied mostly by Ledan Schists with metamorphic events leading to magnetite destruction. The interpretation redefines the distribution of Palaeoproterozoic lithologies, including granites, as presented on very dated published 1:250,000 scale mapping