Tapping geoscience energy in the Curnamona
Cross-border collaboration in the Curnamona Province has been strengthened following the recent UNCOVER Curnamona conference in Broken Hill.
Ideas for new collaborations under an ongoing memorandum of understanding between the Geological Surveys of South Australia (GSSA) and New South Wales (GSNSW) were discussed at a meeting led by Steve Hill (Director) and Chris Yeats (Executive Director). Geologists working in the region are also looking forward to new developments, with the MinEx CRC Bid (which includes the proposed National Drilling Initiative) and its potential application in the Curnamona Province.
Broken Hill is a mining heartland of Australia and has drawn some of the best economic geologists and researchers to it. The work on the Broken Hill orebody and other aspects of the Willyama Supergroup and Olarian Orogeny has revealed much about the metallogenic and tectonic evolution of the Curnamona Province and about fundamental earth processes over the decades. There remains a keen interest in the geology of the Curnamona Province and surrounds, and an optimism regarding prospectivity that has been sustained through difficult economic times for the minerals industry.
UNCOVER Curnamona, held from 26 to 27 July 2017, attracted around 100 participants keen to hear the latest knowledge on the geology of the Curnamona Province and surrounding related regions, such as the Koonenberry Belt. The event was organised by the GSSA, GSNSW and the Geological Society of Australia (GSA).
It provided an opportunity to showcase some of the exciting work being done. Twenty-eight presentations were given from all areas of geoscience, with speakers from the minerals industry, the two geological surveys, CSIRO, Geoscience Australia and academia. Highlights included the integration and uptake of results between industry and government researchers.
The conference was opened by the Mayor of Broken Hill, Darriea Turley, who gave a personal account of the importance of mining to the Broken Hill community. This was followed by Tony Webster on the Broken Hill Line of Lode covering aspects of the mining history and its unique and complex geology.
Presentation from companies actively working in the region brought great depth to the forum. Dean Rogers (Perilya) and Chris Giles (Havilah Resources) gave insightful descriptions of the geology of two active deposits – the Broken Hill orebody and the Portia gold deposit respectively. The geological context for tin and related mineralisation in the Prospect Hill region of the Mount Babbage Inlier was covered by Adrian Brewer (Teale and Associates), while new ideas about nickel – platinum group elements (PGE) mineralisation associated with Neoproterozoic ultramafic rocks in the Curnamona Province were presented by Mike Jones (Impact Minerals). Reflections on the Broken Hill orebody were made via a possible analogue from Mount Isa, the Maronan Pb–Ag deposit, by Rob Rutherford (Red Metals), and potential for cobalt mineralisation in the Thackaringa region was discussed by Anthony Johnston (Broken Hill Prospecting). Finally, there were also talks by Noel Archer (Awati Resources) on orogenic gold potential in the Koonenberry Belt, and Rob Gordon (Silver City Minerals) on possible iron oxide – copper– gold deposit potential in the western Curnamona Province.
The remaining talks were arranged into the four themes of the UNCOVER initiative.
Characterising the cover. John Davidson (GSNSW) presented the GSNSW seamless geology integrated into a 3D model of the region; Camilla Sorensen (CSIRO) presented work on the utility of airborne electromagnetic data in the Frome Basin; and Anthony Reid (GSSA) presented recent work on understanding the provenance and geochemistry of the cover sequences of the Curnamona Province.
Lithospheric architecture. Stephan Thiel and Kate Robertson (GSSA) provided an overview of new Australian Lithospheric Architecture Magnetotelluric Project (AusLAMP) data and the relationship between conductivity in the mantle and crust and uranium mineralisation in the Frome Embayment, as well as the location and possible causes of the large conductivity anomaly beneath the Curnamona Province. John Greenfield (GSNSW) gave an update on the AusLAMP survey across NSW.
Distal mineral footprints. Keynote speaker Roger Skirrow (Geoscience Australia) provided an inspired overview of the mineral systems of the Curnamona Province. New data on the metamorphic petrology of the Broken Hill domain generated via HyLogger™ were discussed by David Tilley (GSNSW), while Eline Baudet (GSSA-sponsored PhD student) presented on the use of geochemistry in the Mesozoic Bulldog Shale for host signatures of mineral systems such as at Prominent Hill and near Lake Frome.
4D geodynamic evolution and metallogenesis. Steve Hore (GSSA) presented new data on 440 Ma events of the Mount Painter region and possible relationship to Ordovician tectonics of the Tasmanides. Phil Gilmore (GSNSW) presented a new synthesis of the Neoproterozoic to Cambrian evolution of the region and John Greenfield (GSNSW) presented work on the metamorphic petrology of the Curnamona Province and its relationship to mineral systems, particularly related to Sn–W bearing pegmatites.
Impact Minerals led the field trip on 27 July to view mafic and ultramafic rocks of the Red Hill Ni–Cu–PGE prospect, southeast of Broken Hill. Also observed were granulite facies Willyama Supergroup rocks, including the Farmcote Gneiss, and Cenozoic silcrete developed in the hinterland to the Murray Basin. A preconference geotour trip exploring the geology of the Broken Hill Line of Lode was led by Tony Webster (University of Tasmania) and geologists from the GSNSW on the 25 July.
The field trip convoy at the Farmcote Gneiss locality. (Courtesy of John Greenfield, GSNSW; photo 415931)
View the presentations given by members of the GSSA.
– Anthony Reid (GSSA), Steve Hill (GSSA), Phil Gilmore (GSNSW), John Greenfield (GSNSW) and Sue Fletcher (GSA)