Abstract
The Frome airborne electromagnetic (AEM) survey was designed to provide reliable pre-competitive AEM data to aid the search for energy and mineral resources around the Lake Frome region of South Australia. Flown in 2010, a total of 32,317 line kilometres of high-quality airborne geophysical data was collected over an area of 95,450 km2 at a flight line spacing mostly of 2.5 km, opening to 5 km spaced lines in the Marree–Strzelecki Desert area to the north. The Lake Frome region hosts a large number of sandstone-hosted uranium deposits with known resources of ∼60 000 tonnes of U3O8 including the working In Situ Recovery operations at Beverley, Pepegoona, Pannikin and Honeymoon, and deposits at Four Mile East, Four Mile West, Yagdlin, Goulds Dam, Oban, East Kalkaroo, Yarramba and Junction Dam. The aims of the Frome AEM Survey were to map and interpret critical elements of sandstone-hosted uranium mineral systems including basin architecture, paleovalley morphology, sedimentary facies changes, hydrological connections between uranium sources and uranium deposition sites and structures. Interpretations of the data show the utility of regional AEM surveying for mapping crucial elements of sandstone-hosted uranium mineral systems as well as for mapping geological surfaces, structures and depth of cover over a wide area. Data from the Frome AEM Survey allow mineral explorers to put their own high-resolution AEM surveys into a regional context. Survey data were used to map and interpret a range of geological features that are associated with, or control the location of, sandstone-hosted uranium mineral systems and have been used to assess the uranium prospectivity of new areas to the north of the Flinders Ranges.
ACKNOWLEDGEMENTS
The authors gratefully acknowledge the contributions made to obtain the Frome AEM Survey data by survey partners The Geological Survey of South Australia, South Australia Department of Manufacturing, Innovation, Trade, Resources and Energy (DMITRE), a consortium led by Callabonna Uranium Ltd (now Callabonna Resources Ltd) and Fugro Airborne Surveys (now CGG). The authors also gratefully acknowledge the contributions of Adelaide Resources Ltd, Alinta Energy Ltd, Areva Australia Pty Ltd, Cameco Australia Pty Ltd, Curnamona Energy Ltd, Eromanga Uranium Ltd, Gold Fields Australasia, Havilah Resources NL, Heathgate Resources, Maximus Resources, Sinosteel-PepinNini Curnamona Management Pty Ltd, Scimitar Resources Ltd (now Cauldron Energy Ltd), Toro Energy and Uranium One Australia Pty Ltd for discussions, access to data, site access and encouragement. A number of people contributed to interpretations used in this paper including Adrian Fabris and Bernd Michaelsen (Geological Survey of South Australia) for paleovalley outlines and discussions of fault structures around the Beverley uranium mine, respectively, and Andrew Cross (GA) and Stephen Hore and Elizabeth Jagodzinski (Geological Survey of South Australia) for discussions on zircon provenance work. The authors gratefully acknowledge the constructive reviews of Alan Whitaker and Terry Mernagh (GA), John Greenfield (Geological Survey of New South Wales) and Steven Hill (Geological Survey of South Australia) that substantially improved the manuscript. ICR is indebted to Steven Hill and Stephen Hore for discussions on the geology and landscape evolution of the northern Flinders Ranges and for their local knowledge imparted during a number of field trips to the Beverley area. This paper is published with the permission of the CEO, Geoscience Australia.