Forbes-Dubbo
MinEx Cooperative Research Centre (MinEx CRC) activities will be undertaken over the Macquarie Arc, in the greater Forbes to Dubbo region (Figure 1).
Location map of the Forbes-Dubbo MinEx focus area
Figure 1: Location map of Forbes-Dubbo MinEx focus area
Current activities
Forbes - Dubbo Airborne Electromagnetic (AEM) Survey
GSNSW and Geoscience Australia will carry out an airborne electromagnetic (AEM) survey to measure the natural electrical properties of rocks and soil to a maximum of 400 metres deep in the Forbes to Dubbo region. These properties vary depending on the type of rocks and soil, and the water content and salinity. The data collected will help to improve our knowledge of the geology and groundwater resources of the area, which will be used to make informed decisions by mineral explorers, the government, and farmers.
This survey is being undertaken to support two projects, MinEx CRC and Future Ready Regions (FRR). FRR is the NSW Government’s commitment to building strong communities and diversified regional economies that are not just built to survive drought but are able to thrive as an economic powerhouse. The data collected from the AEM survey will be used to help identify areas with potential deep groundwater and those that could store groundwater (in times of surplus).
The MinEx CRC project has groundwater synergies with the FRR project and will also focus on minerals and geology, to help NSW discover critical minerals needed for a cleaner, greener NSW.
A specialist and experienced contractor will undertake the survey. An aircraft will fly at a height of between 60 and 120 metres above the ground, along approximately 140 east-west lines. The lines will typically be about 60 km long and up to 2.5 km apart. An interactive map of the survey lines is below.
The data will be made publicly available after it is processed. If you are interested in receiving the data please email us at minex.crc@regional.nsw.gov.au
A comprehensive community engagement plan will be actioned to inform the community and stakeholders about the survey. The survey is proposed for first half of 2023.
Expression of interest for infill
To assist with survey planning we are seeking expressions of interest (EOI) for infill. Infill is a way of attaining closer line spacing data for private and public use. Infill is usually flown with a closer line spacing than our surveys, as we acquire data for regional studies not exploration. Private parties can engage the company we contract and save on mobilisation costs. Infill data has a one-year confidentiality, then is publicly released. For more information of on the AEM survey and how to submit an EOI go here (PDF, 1.63 MB).
Proposed survey area
Proposed AEM survey area for the Forbes-Dubbo area (Download zipped shapefile)
Geological mapping and sampling
Rock samples will be collected from outcrops and existing drillhole material during ongoing field mapping and core library visits. Samples will be analysed for geochemistry, mineralogy and age dating. View more information and a video explaining geological mapping here.
The data acquired will be analysed and synthesised and gradually made available through MinView. Results will also be incorporated into the NSW Seamless Geology Geodatabase, which is available on MinView.
Completed activities
Two audit and gaps studies of the area are available on DIGS (GS2019/1238 and GS2020/0185). Ongoing geological mapping and sampling will address recommendations in this report.
Hydrogeochemistry
A 60-sample hydrogeochemistry (water sampling) survey was completed between July and October 2020 as part of an initial study of groundwater chemistry in the Forbes region (see figure below). Each sample was analysed for a range of elements as well as parameters such as salinity and pH. As part of the survey, an additional 13 samples were collected for radiocarbon dating to provide insight into the residence times of groundwaters in the region. The analytical results were forwarded to landholders in July 2021 and are available on MinView. To download the data, click Tools > Data download > Hydrogeochemistry.
The results of this survey are currently being synthesised in an interpretive report (by CSIRO and Geological Survey of NSW researchers), which is expected to be made publicly available in mid-2022.
Figure 2: Map showing the Forbes MinEx CRC hydrogeochemistry sample locations overlain onto the surface geology layer of the NSW Seamless Geology dataset.
Whole rock geochemistry
10 new whole rock geochemical analyses have been obtained across several igneous units in the Forbes region through a combination of outcrop and drillcore sampling. A comprehensive suite of elements as well as bulk-density was determined for each sample, which cover a range of basic through to silicic rock types. The units sampled include the Currumburrama, Parkes and Carawandool volcanics, and the Bundaburrah Granodiorite. The analytical results are now available for download on MinView, as part of GSNSWs whole rock geochemistry dataset. To download the data, click Tools > Data download > All whole rock geochemistry. Within this dataset the new analyses within the Forbes focus area are found by searching the dataset using the sample number project identifier ‘MXFO’.