There is increasing demand from policy makers for high levels of certainty before committing to decisions on water security infrastructure. This demand for higher certainty in groundwater model predictions has provided an impetus for new hydrogeological research directions. This has included a renewed impetus in the search for technologies and methods to aid rapid groundwater resource assessment. Critical measurements used to parameterise groundwater models include effective porosity and hydraulic conductivity measurements. Typically, values for effective porosity are derived by lithological comparisons with published data, and measurements of hydraulic conductivity acquired by limited constant head pumping tests or slug tests. Look-up tables are used for deriving effective porosity as a surrogate for expensive and time consuming laboratory measurements of cores that may be biased by sampling, and the difficulty of making measurements on unconsolidated materials. However, pump tests are costly and time-consuming, with environmental permissions for disposal of produced waters increasingly difficult to obtain. Nuclear Magnetic Resonance (NMR) can provide a direct measurement of the presence of water in the pore space of aquifer materials. The detection is possible due to the nuclear magnetization of the hydrogen (protons) in the water. The NMR measurement is the basis of MRI (magnetic resonance imaging) in medical applications, and geophysical logging applications within consolidated sediments for the petroleum industry. In the Darling River floodplain, NMR data were acquired in 26 boreholes in a 4-week period. Effective porosity values were derived directly from the NMR data, and hydraulic conductivity values were calculated using empirical relationships calibrated and verified with limited laboratory permeameter and field aquifer tests.

The Gilmore Project is a pilot study designed to test holistic systems approaches to mapping mineral systems and dryland salinity in areas of complex regolith cover. The project is coordinated by the Australian Geological Survey Organisation, and involves over 50 scientists from 14 research organisations. Research partners include: Cooperative Research Centres for Advanced Mineral Exploration Technologies (CRC AMET), Landscape Evolution and Mineral Exploration (CRC LEME), the CRC for Sensor Signal and Information Processing, and the Australian Geodynamics Cooperative Research Centre (AGCRC) Land & Water Sciences Division of Bureau of Rural Sciences (BRS) NSW Department of Land & Water Conservation and the NSW Department of Mineral Resources. Various universities including the Australian National University, University of Canberra, Macquarie University, Monash University, University of Melbourne, and Curtin University of Technology, and Australian National Seismic Imaging Resource (ANSIR). The project area lies on the eastern margin of the Murray-Darling Basin in central-west NSW. The project area was chosen for its overlapping mineral exploration (Au-Cu) and salinity management issues, and the availability of high-resolution geophysical datasets and drillhole materials and datasets made available by the minerals exploration industry. The project has research agreements with the minerals exploration industry, and is collaborating with rural land-management groups, and the Grains Research and Development Corporation. The study area (100 x 150 km), straddles the Gilmore Fault Zone, a major NNW-trending crustal structure that separates the Wagga-Omeo and the Junee-Narromine Volcanic Belts in the Lachlan Fold Belt. The project area includes tributaries of the Lachlan and the Murrumbidgee Rivers, considered to be two of the systems most at risk from rising salinities. This project area was chosen to compare and contrast salt stores and delivery systems in floodplain (in the Lachlan catchment) and incised undulating hill landscapes (Murrumbidgee catchment). The study area is characteristic of other undulating hill landscapes on the basin margins, areas within the main and tributary river valleys, and the footslopes and floodplains of the Murray-Darling Basin itself. Studies of the bedrock geology in the study area reveal a complex architecture. The Gilmore Fault Zone consist of a series of subparallel, west-dipping thrust faults, that juxtapose, from west to east, Cambro-Ordovician meta-sediments and granites of the Wagga Metamorphics, and further to the east, a series of fault-bounded packages comprising volcanics and intrusions, and siliciclastic meta-sediments. Two airborne electromagnetic (AEM) surveys were flown in smaller areas within the two catchments. Large-scale hydrothermal alteration and structural overprinting, particularly in the volcanics, has added to the complexity within the bedrock architecture.

In this paper, we report the results of analysing data where the same flight line has been flown repeatedly. When these data are corrected for the effects of variable survey altitude they provide a good measure of the reproducibility of AEM data. The analysis has been conducted for a variety of frequency and time domain systems and has demonstrated that the realistic noise levels can be up to 5 to 10 times larger than those normally quoted. In addition, in order to characterise the measurements accurately, it is necessary to consider both multiplicative (percentage) and additive errors.

Under the Community Stream Sampling and Salinity Mapping Project, the Australian Government through the Department of Agriculture, Fisheries and Forestry and the Department of Environment and Heritage, acting through Bureau of Rural Sciences, funded an airborne electromagnetic (AEM) survey to provide information in relation to land use questions in selected areas along the River Murray Corridor (RMC). The proposed study areas and major land use issues were identified by the RMC Reference Group at its inception meeting on 26th July, 2006. This report has been prepared to facilitate recommendations on the Boundary Bend - Nyah study area. The work was developed in consultation with the RMC Technical Working Group (TWG) to provide a basis for the RMC Reference Group and other stake holders to understand the value and application of AEM data to the study area. This understanding, combined with the Reference Groups assessment of the final results and taking in account policy and land management issues, will enable the Reference Group to make recommendations to the Australian Government.

Exploring for the Future (EFTF) is a four-year geoscience data and information collection programme that aims to better understand on a regional scale the potential mineral, energy and groundwater resources that are concealed under cover in northern Australia and parts of South Australia. This factsheet explains one of a range of activities being undertaken to collect these data and information.

Ashmore Reef, 12°20 South, 123°0 E East, is a category one, Marine Protected Area administered by the Australian Government under the Environmental Protection and Biodiversity Conservation Act 1999. It is named after Irish, free mariner, Charles Samuel Ashmore, captain of the mercantile brig 'Hibernia'. He located, named and charted parts of Ashmore Reef on the 11th June, 1811. Since then there has been a range of Navy and research vessels who have continued the charting effort. Such traditional work has been supplemented by data from airborne laser bathymetric technology and Royal Australian Air Force photography. We present a maritime mapping history of Ashmore Reef and demonstrate the range of technologies which have influenced the progression of mapping processes over time. The advancement in sounding / data density and its presentation has been important for the management of Ashmore Reef as the Marine Protected Area is largely guided by the 50 metre contour and latitude and longitudinal references. Onsite compliance and enforcement of the EPBC Act 1999 is provided by personnel from the Australian Custom Service, National Marine Unit.

Presentation to minerals industry representatives at the Geological Survey of Western Australia, 4 May 2010

This record reports on an AGSO/PIRSA/CRC LEME/Dominion Mining AEM Interpretation Workshop. The workshop focused on AEM data acquired over the Challenger Prospect in South Australia.

Displays the coverage of publicly available digital gamma-ray spectrometric data. The map legend is coloured according to the line spacing of the survey with broader line spacings (lower resolution surveys) displayed in shades of blue. Closer line spacings (higher resolution surveys are displayed in red, purple and coral.

The Natural Fields EM Forum was held in Brisbane, Queensland, Australia, on February 26, 2012, in conjunction with the ASEG 22nd International Geophysical Conference & Exhibition 2012. The forum was organised to review the current state of development of natural field EM methods (NFEM), being those methods that utilise the ambient electromagnetic field rather than deploying an additional active source as an element of a survey. NFEM methods are used to acquire data from which various parameters can be obtained to help interpret the electrical characteristics of the subsurface.