DMITRE Minerals

Jump to content

Search

 

Navigation

 

TEiSA 2020

TEiSA press release

TEiSA 2020 reflects the target date for completion of the vision set by the Resources Task Force and the State Resources Plan. New funding recently announced under TEiSA 2020 will ensure that the mineral and petroleum exploration industry has continued access to pre-competitive geoscientific data. The South Australian Government has allocated an initial $1.14 million in new funding to acquire strategic geoscientific data under this new initiative. The funding will increase to almost $2 million per year over five years, when it will become part of the core budget.

The objectives of TEiSA 2020 are to:

  • reduce exploration risk for minerals and petroleum in key areas of the state (Musgrave Block, Gawler Craton, Curnamona Province and Officer Basin) through improved understanding of their prospectivity and enhanced access to critical data to support business decisions
  • develop methods to see through the cover sediments which obscure most of these highly prospective regions
  • promote South Australia’s competitive advantages, nationally and internationally, as an exploration destination
  • increase exploration, new mineral discoveries, developments and production in line with targets identified in the government’s State Resources Plan developed in response to the Resources Task Force recommendations.

TEISA 2020 Press Release

 

Current minerals projects

Willyama Architecture and Mineral Potential

Detailed geological mapping (1:25 000 scale) continued in key areas of the Willyama Inliers. Mapping was completed and is available digitally for the Radium Hill North and South areas (Mingary 1:100 000 sheet area) and the Coppertop Inlier (Winnininnie 1:100 000). In addition, contractor Geosurveys Australia completed syntheses and interpretations of previous mapping in the Outalpa Inlier and Billeroo area. Mapping is underway in the Mingary North and South and Billeroo North 1:25 000 map areas, and Morialpa and Walparuta Inliers. A draft report and map has been received from Geoscience Australia on the structure and stratigraphy of the Ameroo Hill area.

A comprehensive new field guide to the Willyama Inliers and a compilation and reinterpretation of data on metamorphic grade across the Olary and Broken Hill Domains are both near completion. A MESA Journal article on the architecture and nomenclature of the Willyama Inliers has been published.

CSIRO Mineral Exploration is undertaking processing of ASTER satellite remote sensing data across the Curnamona Province for the Curnamona Program, with the objective to produce seamless mineral maps to assist geological mapping particularly of major alteration features.

Curnamona Tectonic History

A collaborative University of Adelaide study provided new geochemical and isotopic data on the provenance of the Willyama Supergroup and Bimbowrie Suite granites. A paper on stratigraphic correlations between Olary and Broken Hill Domains incorporating recent geochronology for international journal publication is nearing completion.

A major new program of U–Pb geochronology on Willyama Supergroup metasediments and volcanics and later intrusive phases in South Australia and New South Wales has commenced in collaboration with Dr Rod Page of ANU, Geoscience Australia and the Cooperative Research Centre for Predictive Mineral Discovery.

Three PIRSA-supported collaborative research projects have received Australian Research Council funding approval. The projects ‘Magma, metamorphism and mineralisation’ (University of Adelaide), ‘Early tectonic evolution’ (Monash University) and ‘Fluid processes’ (University of Adelaide) are designed to provide a major improvement in understanding of the geological and mineralising history of the Curnamona Province, thereby leading to better targeted exploration.

Greenstone Drilling Project Phase 2

The Greenstone Drilling Project Phase 2 was carried out from 7 June to 8 August 2002 as a follow up to the phase 1 drilling which was completed during May–August 2001. A total of 61 drillholes were completed for 3110.45 m, comprising 2680.7 m of aircore and open hole percussion and 429.75 m of diamond coring. The drilling provided undisturbed core for regolith studies, and information on the age and distribution of palaeochannel sediments. Regional drillholes discovered a new occurrence of komatiite 3 km east of Kenella Rocks and finalised four detailed drill traverses across the strike of the metakomatiite-bearing sequence in the Mullina Well area. Two regional drill traverses further defined depths to basement and basement lithology.

Of the four drill traverses in the Mullina Well area, the westernmost traverse at 461100E identified a metabasalt–metakomatiite-bearing sequence with an estimated width of ~300 m. The traverse at 468650E, initiated in phase 1 drilling, was extended to the south and sampled the basal section of the metakomatiite-bearing sequence. The drillholes penetrated alternating bands of metakomatiite and previously unrecognised, low metamorphic grade, highly sheared metasediment. A drill traverse at 471000E identified a much-reduced thickness of metakomatiite with a similar basal sequence of metasediment. Three holes were drilled to test an airborne electromagnetic anomaly near Kenella Rocks. The source of anomalism was identified as graphite-bearing rock.

Geochemical results include elevated gold values in TAR 119 (18–59 m, 41 m at 23 ppb in weathered metakomatiite), TAR 127 (42–54 m, 12 m at 25 ppb in highly sheared metasediment) and KEN 1 (71.7–72 m at 30 ppb in a mafic rock). Metakomatiite was readily identified by its elevated nickel and chromium values which were generally >1000 ppm. The best intersection was TAR 132 with 28.5 m (82–110.5 m) at 2400 ppm Cr and 1130 ppm Ni; platinum and palladium values were slightly elevated.

Landscape evolution

Module 1 — Regolith

The Landscape Evolution Regolith Project involves detailed regolith mapping of selected areas of the Harris Greenstone Belt along with detailed regolith subsurface modelling based on drillhole data. The Harris Greenstone Belt is covered by thin surficial sediments and has been affected by moderate to deep weathering (<10–>100 m). To undertake efficient geochemical exploration over the greenstones, relationships between geochemical dispersion patterns, weathering processes and evolutionary stages of regolith and landform development needed to be studied. The Landscape Evolution Project will characterise the regolith within the greenstone Belt and allow comparisons with regolith development in more established geochemical exploration regions in Western Australia.

Preliminary results show a high variability in the depth of weathering and extent of preserved weathering profile. A good correlation has been established between depth of weathering and response to airborne electromagnetics. Samples have been submitted for geochemical analysis, with results expected in the near future. This will allow the dispersion effects of selected elements within the regolith to be studied in more detail.

Module 2 — Sedimentary Synthesis

The Sedimentary Synthesis Project is aimed at updating the differences in mapped sedimentary geology over the Harris Greenstone Belt. As it is important for explorers to understand the sedimentary geology if they are to explore effectively, this project will reconcile these differences by production of a revised sedimentary stratigraphy and an ‘explorers guide’ to mapping and logging the sedimentary cover.

The production of stratigraphic unit identification sheets is underway and will be collated into a sedimentary guide to the Harris Greenstone Belt.

Module 3 — Kingoonya Palaeochannel

The Kingoonya Palaeochannel Project is a sedimentological study of the main palaeochannel crosscutting the Archaean greenstones and adjacent Proterozoic goldfields in the central Gawler Craton. The aim is to better define the palaeochannel systems developed across the Harris Greenstone Belt and define target areas within these systems which have potential for placer deposits (gold, diamonds, uranium and heavy minerals) and for determining mineralisation in the basement. The study will enhance the understanding of the area’s landscape evolution, groundwater resources and regolith development, and allow a better understanding of the results from exploration geochemistry.

Relogging of existing drillholes is complete, allowing a better interpretation of true depth to basement and palaeochannel dynamics. Preliminary interpretation of geophysical and remote sensing data is underway and has already revealed previously unrecognised palaeochannel systems. Five holes have been drilled into palaeochannels as part of the phase 2 drilling to determine the physical parameters of these systems.