Minerals Alert

October 2017

A monthly online newsletter with product news, data releases and project highlights relating to the minerals and energy exploration industries.

  1. New Geochronology Report
  2. Southern Thomson Project: Completion of stratigraphic drilling
  3. Exploring for the future - first data release
  4. Update on geophysical data release
  5. About Minerals Alert

1. New Geochronology Report

GA Record 2017/16 (http://dx.doi.org/10.11636/Record.2017.016) by Kositcin and Carson reports new SHRIMP U-Pb zircon ages from nine samples of sedimentary rocks collected from the Paleo- to Neoproterozoic Birrindudu Basin and Victoria Basin, northwest Northern Territory. This work is part of Geoscience Australia's Exploring for the Future initiative. The newly acquired SHRIMP U-Pb data assist in the determination of maximum depositional ages and sedimentary provenance during the evolution of the Birrindudu Basin and Victoria Basin, and contribute to our understanding of lithostratigraphic correlations with other Proterozoic basins across northern Australia, such as the greater McArthur Basin and the Centralian Superbasin.

For further information, email clientservices@ga.gov.au or phone 1800 800 173.

2. Southern Thomson Project: Completion of stratigraphic drilling

The southern Thomson Orogen stratigraphic drilling program was successfully completed on 12 September 2017. The Southern Thomson Project (the Project) is a collaboration between Geoscience Australia (GA) and its state partners; the Geological Survey of New South Wales(GSNSW) and the Geological Survey of Queensland (GSQ). The Project sits within the national UNCOVER Initiative, which aims to reverse the decline in Australia's known mineral reserves by providing new information to explorers about undercover regions.

Very little is known about the evolution and prospectivity of the rocks of the southern Thomson Orogen as the majority are buried underneath younger sedimentary rocks of the Eromanga Basin. The program of ten stratigraphic boreholes (locations in Figure 1) adds to the two boreholes drilled in the Eulo region of Queensland in 2016. All twelve boreholes tested distinctive basement terranes identified from geological-geophysical interpretation. The boreholes were successfully drilled using a combination of rotary mud drilling through cover sequences and diamond drilling of underlying basement rocks to provide a nominal 50 metres of representative core samples from each site. Wireline geophysical logs were run in the holes prior to casing to obtain petrophysical data for further geophysical modelling. Total borehole depths and preliminary basement lithologies are summarised below:

Site ID (ref Figure 1)

Total Depth (m)

Basement Lithology

GSQ Eulo 1(drilled 2016)

379.3

Greenschist facies metasediments

GSQ Eulo 2 (drilled 2016)

135.5

Altered intermediate volcanics

GSNSW Milcarpa 1

290.9

Rhyodacite porphyry

GSNSW Euroli 1

153.7

Metasedimentary schist

GSNSW Tongo 1

312.8

Granodiorite

GSNSW Laurelvale 1

386.8

Siliciclastic turbidite black slate

GSNSW Janina 1

222.2

Granite

GSQ Eulo 3

171.1

Interbedded metasediments

GSQ Eulo 4

357.6

Turbiditic metasediments and intermediate-mafic porphyry intrusive

GSQ Cunnamulla 1

632.4

Foliated metasiltstone and fine grained sandstone

GSNSW Congarrara 1

119.6

Sheared quartz-biotite schist

GSNSW Congarrara 2

317.8

Granite


Map of bourke region of Queesland and New South Walses where boreholes are being drilled

Figure 1: Location of Southern Thomson Orogen stratigraphic boreholes in the
Cunnamulla - Hungerford -White Cliffs - Bourke region of Queensland and New South Wales.


The range of basement samples acquired from the drilling program give Project scientists a new range of materials to analyse and better place the southern Thomson Orogen into the wider context of eastern Australian geodynamics and mineral prospectivity. All cores have been scanned using Hylogger™ and will be comprehensively sampled for mineralogy, geochemistry and geochronological analysis. Final results will be made publicly available through the GA, GSNSW and GSQ websites and presented at Southern Thomson Project workshops.

For further information, email clientservices@ga.gov.au or phone 1800 800 173.

3. Exploring for the Future - First Data Release

On 15 September Geoscience Australia released via the Geophysical Archive Data Delivery System (GADDS) the data from a Gravity Survey in the South Nicholson area of the Northern Territory. This was the first gravity survey completed under the Exploring for the Future Programme which aims to better understand the potential mineral, energy and groundwater resources in northern Australia and parts of South Australia. The survey was conducted in  July 2017 and collected 2,724 new gravity stations at 4km spacing over an area of 43,330 square kilometres on the NT side of the NT-QLD border from Mount Drummond to Sandover River.

4. Update on geophysical data release

Geoscience Australia is managing the geophysical data acquisition programs in Western Australia, Victoria, New South Wales, Queensland, Tasmania and the Northern Territory on behalf of the state/territory geological surveys

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

For further information, email clientservices@ga.gov.au or phone 1800 800 173.

5. About Minerals Alert

For more information, please email clientservices@ga.gov.au; or phone 1800 800 173.

To read past editions of Geoscience Australia's Minerals Alert, visit the Minerals Alert Newsletter Archive.

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