Location: 90 kms south east of Charters Towers, North Queensland
Geological Province: Drummond Basin, Queensland
Ground Holding: 2 tenements comprising 270 sq kms
Ownership Status: 100% owned by Adelaide Resources
- Rock chip sampling support widespread anomalous gold in vein material
- vein textures and presence of signature epithermal pathfinder elements and petrological study confirm target epithermal mineralisation style
- successful trial FPXRF soil geochemistry defines very strong arsenic anomalies
- proven strong gold and arsenic association
- similar geological characteristics to the ~3 million ounce Pajingo Field located 70 kms to the west
- significantly under-explored with only ~20 historic holes drilled
Adelaide Resources holds 100% equity in EPM 18090 and EPMA 25660 which together secure 270 sq kms of ground in the northern Drummond Basin in Queensland. There are no third party interests, royalties or other encumbrances on either of the tenements.
Drummond Epithermal Gold Project location plan
Geological Setting – The Drummond Basin
The Drummond Basin in Queensland hosts a number of significant, high grade epithermal gold deposits, the most notable being the ~3 million ounce Pajingo Field.
The Company’s Drummond Epithermal Gold Project tenements secure volcanic dominated stratigraphy of the Drummond Basin just south of the interpreted boundary with older Mt Windsor Volcanics and intrusives of the Lolworth-Ravenswood Block, a geological setting similar to that seen at the Pajingo Field, located about 70 kilometres to the west.
An epithermal gold deposit is one in which gold mineralisation is deposited relatively close to the ground surface from hot volcanic fluids. The fluids are estimated to range in temperature from less than 100°C to about 300°C and, during the formation of a deposit, can appear at the surface as hot springs and geysers. Gold is carried in solution and is deposited when the water approaches the land surface and boils. Epithermal deposits are formed during periods of active volcanism around the margins of continents, a geological situation that existed in the Drummond Basin during the Late Devonian to Carboniferous.
Epithermal deposits exhibit a number of characteristic geological features including specific vein textures, alteration assemblages and the presence of associated pathfinder metals, all of which vary depending upon the vertical position in the system. A general model of an epithermal deposit is shown below.
Geological model of an epithermal gold system
Previous explorers located gold mineralised systems on the area secured by EPM 18090. At the Limey Dam prospect, historical soil sampling delineated a cluster of gold anomalies in a five kilometre long, northeast trending corridor. Rock chip samples collected from outcropping quartz veins returned anomalous gold values with a best result of 3.15g/t gold. Limited drilling at Limey Dam returned 40 metres at 0.19g/t gold from 23 metres, 12 metres at 0.48g/t gold from surface and 14 metres at 0.38g/t gold from 42 metres.
Commencing in 2013 the Company completed a highly successful first exploration program on EPM 18090 “Glenroy”, which included rock chip sampling, trial FPXRF pathfinder soil geochemistry, and a petrological study of vein and host rock materials.
Assaying of rock chips confirmed the presence of anomalous gold and epithermal pathfinder metals, including one sample from the South West Limey Dam prospect which returned 55.4g/t gold.
The FPXRF soil geochemistry trials showed that the method is able to successfully define epithermal gold pathfinder metal anomalies at a resolution sufficient to allow the direct targeting of drill holes.
Rock chip sample from South West Limey
Dam assaying 55.4g/t gold.
FPXRF sampling conducted on a semi-systematic grid at the South West Limey Dam prospect revealed a large and coherent arsenic anomaly containing internal narrow high magnitude zones. Initial traverses of FPXRF soil geochemistry at other prospects indicate the presence of similar strongly anomalous arsenic in areas that show every chance of developing into further highly regarded anomalies with systematic sampling.
South West Limey Dam prospect FPXRF summary
More recent field exploration work has now identified 3 discrete epithermal quartz gold bearing veins at the South West Limey Dam prospect which have been named the Alexandra, Nadia and Anna veins.
The east-west trending Alexandra vein has been traced alsong strike for 250 metres and has returned a number of very high grade gold rock chip samples assaying 51.5g/t gold, 31.0g/t gold, 26.9g/t gold and 21.7g/t gold over a 50 metre long sectiion of the vein. The nearby east-west trending Nadia vein has been mapped over 95 metres and includes rock chip sample results of 55.4g/t gold, 34.2g/t gold, 9.32g/t gold and 7.99g/t gold on a 30 metres section. The north-south striking Anna vein has been traced over 750 metres along the western edge of the South West Limey Dam prospect with rock chip assay results returning 6.93g/t gold, 6.33g/t gold and 4.53g/t gold.
South West Limey Dam prospect rock chip summary
The petrological study confirmed the presence of signature epithermal textures including colloform and crustiform banding and bladed calcite textures considered indicative of fluid boiling in mineralised veins. Alteration mineral assemblages typically seen in epithermal systems were also observed in the volcanic host rocks.
In 2013, the Queensland Government announced collaborative drilling funding as part of its “Future Resources Program”. The Collaborative Drilling Initiative (CDI) is designed to encourage the testing of new exploration concepts with economic and technical merit by directly supporting companies to drill high quality exploration targets in greenfield and under-explored areas of Queensland to stimulate the discovery of a new generation of mineral and energy resources.
Adelaide Resources applied through the Collaborative Drilling Initiative for funding to complete a program of up to 2800 metres of reverse circulation drilling to test an epithermal gold target at the South West Limey Dam prospect delineated by the 2013 FPXRF soil geochemistry survey.
The Company’s application was successful with the Queensland Government to contribute up to a maximum of $100,000 to fund 50% of the direct drilling costs of the exploration program. Adelaide Resources will fund the remainder of the drilling costs, along with associated expenses such as field personnel and assaying charges. A condition of the Collaborative Drilling Initiative funding agreement requires that the program of drilling is completed by 13 April 2016.