The remote northwest of NSW is the state’s most underexplored and poorly understood geographic region.



The area represents the southern end of the sprawling and undulating geologic formation known as the Thomson Orogen. It has defied explorers for generations with stubbornly thick cover and uncomfortable climatic conditions.



A research project under the NSW government’s New Frontiers initiative helped attract a considerable amount of industry attention in the area in 2005-10, but the global financial crisis soon thinned out the high-risk activity until only a few true believers remained.



The region is so conspicuously underexplored that it has been singled out as the test subject for an ambitious airborne electromagnetic survey aiming to map the entire continent.



Before the broader survey is rolled out across other challenging geologic regions, the southern Thomson Orogen will undergo in-development techniques to measure cover by applying multi-covariate modelling and advanced sample designs of existing datasets.



As part of the effort, a three-year collaborative research program will be carried out by Geoscience Australia, the Geological Survey of NSW and the Geological Survey of Queensland.



“We see it as a key greenfields area,” Geoscience Australia group leader of regional geology and mineral systems Richard Blewett told MiningNewsPremium.net



“When we first came to look at the area and look at the drill holes, there were virtually none.



“We’re basically going to do all the prep, work out the questions we need to ask and then go drill.



“Our aim is to de-risk the southern Thomson.”



Initial electromagnetics and geochemical sampling will begin this year and drilling is planned to follow from 2014-15.



New information derived from the project is expected to determine depth to basement and cover characterisation, with final results delivered in mid-2016.



This final unmasking of NSW’s northwest follows on the years of quiet background work under New Frontiers.



Under that program, Thomson Orogen project senior geophysicist Rosemary Hegarty produced the first map of what might lie under the region’s notorious regolith.



With this unique familiarity for the southern Thomson, she defends the region’s mineral prospectivity.



“We know the units are down there, but we just don’t have the hard-rock samples to work with,” Hegarty said.



“Core can help confirm or deny some of the perceptions we’ve got from studying geophysical data so far. It’ll be very helpful in providing the reality check that you need sometimes in a new province like this.”



The exodus of industry activity following the GFC put something of a freeze on our fledgling understanding of the southern Thomson.



But after companies walked away from project sites, their data often became available in the public arena, where it could be integrated for the first time into an increasingly useful geological framework.



Hegarty says these efforts at amalgamating scattered datasets will ultimately lead to the area’s rediscovery by mining companies.



“Once the new project with Geoscience Australia kicks off and it starts to brew some results, we’re absolutely certain they’ll be something we didn’t know was there and people will find interesting,” he said.



Companies already finding things interesting have been quietly following sniffs of extensions to the region’s rare outcropping occurrences and the complex Cobar superbasin system which trails in from the more southerly Lachlan Orogen.



Thomson Resources controls a range of tenements in the area and says it has proven that magnetic anomalies under cover in northwest NSW are associated with base and precious metal mineralised systems.



The company notched eight positive results after testing the nine most prominent magnetic anomalies over a distance of 150km. Best gold results from Thomson’s largest project site have returned 5.5m at 1.3 grams per tonne from 448.5m down hole including 1m at 3.7gpt.



Meanwhile, Meteoric Resources has recorded intersections of 20m at 5.2gpt gold from 8m and 4m at 11.3gpt gold from 36m at its Tibooburra project.



The “Tibooburra dome” represents an instance of rarely shallow bedrock in the southern Thomson and, as host of the Albert Goldfield, is perhaps the most historically active mining area in the broader region.



Although a strategy rethink within Meteoric is likely to result in the offloading of Tibooburra, the scattered but encouraging data so far and the success of the 19th century old-timers has inspired explorer Awati Resources to queue up to take control of the project.



This sense that the potential of the southern Thomson is greater than currently recognised seems set to be handily complimented by renewed efforts of the research community to open up the region.



Hegarty even hinted that the rising bedrock effect of the Tibooburra dome could be repeated in the southern Thomson’s dramatically deformed central area, where a water bore has delineated granite at just 60m depth.



At this point, however, there are far too many missing pieces to make a map of this puzzle – but that’s what exploration is all about.