Update on geophysical data releases

Geoscience Australia will be managing the data acquisition program in New South Wales, Queensland, Western Australia and the Northern Territory.

The current status of Geoscience Australia’s geophysical survey data acquisition is available in a comprehensive table.

Minerals Alert Geophysical Surveys Table – survey boundary polygons in MapInfo TAB format.

Seismic and magnetotelluric data released for Youanmi Survey in Western Australia

The Youanmi deep crustal seismic survey was acquired in 2010 and extends nearly 700 kilometres over the Youanmi Terrane and Eastern Goldfields Superterrane of the Yilgarn Craton. This project was a collaboration between Geoscience Australia and the Geological Survey of Western Australia (GSWA). Funding was provided from the Western Australian Government’s Exploration Incentive Scheme, and Geoscience Australia’s Onshore Energy Security Program. The survey consists of three traverses with a total length of 695 kilometres. These seismic, magnetotelluric and gravity data aim to image the northern Yilgarn Craton from its north-western margin to the Ida Fault, near Leinster.

These data combined with the 2001 Northern Yilgarn and the 2010 Capricorn deep crustal reflection surveys result in a complete section across the northern Yilgarn Craton.

The processed SEG Y data, TIFF images, location information, magnetotelluric and gravity data are available and can be downloaded from the Seismic Acquisition and Processing project.

Interpretations of the seismic sections and magnetotelluric models undertaken by GSWA and Geoscience Australia geologists will be released in February 2013 at a public workshop in Perth.

A cooperative venture between Governments and the mining industry will boost available seismic data being acquired in Western Australia.

Joint survey to increase knowledge

Geoscience Australia Record 2012/04 contains abstracts from the Australian Society of Exploration Geophysics (ASEG) Natural Fields EM Forum 2012, held at the recent ASEG 2012 Conference in Brisbane.

The report is a collation of abstracts presented at the forum and reviews the current state-of-the-art use of natural EM fields in exploration applications. It also includes details of significant developments in acquisition, processing and interpretation methods in recent years, many of which have been made possible through ready access to increased computing power, both in the field and in post-acquisition processing facilities.

Principally, these applications involved aspects of ground-based MT and AMT methods, but also included airborne techniques (e.g., ZTEM) which use only natural EM fields as an energy source. The abstracts cover a wide range of applications of natural EM fields which are used in the search for minerals and energy resources and range from the development of broad-scale regional models to direct detection of drill targets.

The record is available as a free download.

There will be a half-day workshop in Perth, Western Australia on Tuesday 7 June, 2011 starting at 9:00am, at The Celtic Club Inc., 48 Ord Street, West Perth.

Registration forms containing details of the workshop in Perth are available online, and further details are available on the Australasian Institute of Mining and Metallurgy (AusIMM) Uranium Conference web page.

The Pine Creek airborne electromagnetic survey results are now available as a free download.

Geoscience Australia’s Pine Creek AEM survey is one of the three regional AEM surveys funded by the federal government as part of its Onshore Energy Security Program (2006-2011). The results and details of the first AEM survey in the Paterson region of WA are reported in a GA record. The results of the second AEM survey, the Pine Creek survey in NT, were presented, in summary, at a workshop in Alice Springs in March 2011. The full GA record is in progress. Interpretation for the third survey, the Frome survey in SA, is currently in progress.

The Perth workshop will present a summary of the results of the Pine Creek AEM surveys in NT, including data acquisition, processing, geological interpretations and implications for uranium and gold.

Under Geoscience Australia’s Onshore Energy Security Program (OESP), Airborne Electromagnetic (AEM) data is being acquired in areas considered prospective for unconformity-related and palaeochannel-hosted uranium deposits. The program is aimed at reducing exploration risk and promoting exploration activity.

The surveys, which are part of the Airborne Electromagnetic Acquisition and Interpretation project, are designed to reveal new information about regions by acquiring the AEM data at line spacings of one to six kilometres over relatively large areas. The improved understanding of the regional geology resulting from the surveys will be of considerable benefit to mining and mineral exploration companies, which can obtain more detailed data over a specific area of interest by contributing additional funds to the acquisition cost.

As well as enhancing the search for uranium and other energy sources, the survey results will be relevant in exploration for a variety of commodities and other resources, including groundwater. Three priority projects emerged from mineral systems analysis and discussions with the State and Northern Territory Geological Surveys. They are:

1. Paterson Province (Western Australia)
2. Pine Creek (Northern Territory)
3. Frome Embayment (South Australia)

Frome AEM survey Phase 1 data released March 2011. See below for details and free data downloads.

The Woolner Granite and Rum Jungle AEM 2010 Survey infill areas – Phase 1 data released 11 April. See below for details and free data downloads.

Pine Creek AEM Survey Workshop

The AEM project will be presenting a free summary workshop providing information about the results and interpretations of Geoscience Australia’s recently acquired and processed Pine Creek AEM survey data. Presentations will include a summary of the AEM data acquisition program and the nature of the data collected, the geological interpretations, an overview of the mineral systems and new ideas resulting from the program. Time is also included for questions and discussion.

• Perth, Western Australia: Tuesday, 7 June 2011 (prior to the Australasian Institute of Mining and Metallurgy (AusIMM) Uranium Conference). Download the registration form in Word or PDF format.