Emmerson Resources Limited (ASX:ERM) has identified large-scale and pervasive alteration in an expanded auger drilling program at the Whatling Hill copper-gold prospect within its wider Fifield Project in NSW.
Geochemical results are still pending but initial indications show correlation with previous rock chip results which graded up to 2% copper and 0.25 g/t gold in quartz stockwork veins within altered monzonite intrusives.
Once assays have been interpreted Emmerson will target the most prospective areas to undertake geophysical induced polarisation (IP) surveys.
The IP surveys will provide insights into the underlying alteration and mineralisation ahead of drilling.
Emmerson managing director Rob Bills said the expanded geochemical survey at Whatling Hill continued to exhibit the hallmarks of an early-stage discovery.
Bills said: “Alteration and quartz-veining from this expanded auger drill program suggests extensions of the original mineralisation to the south.
“Assay results are pending and, if positive, will provide a focus for future geophysical and drilling programs.”
Bills said the company had demonstrated its confidence in the prospectivity and potential of the area by expanded its ground position in the region.
He added: “These copper-gold porphyry deposits typically cluster and we are in a very fertile metallogenic province, bounded by the Macquarie Arc and Lachlan Transfer Zone.”
Alteration encountered by the auger drilling consists of widespread epidote and chlorite alteration which is consistent with intersecting the outer zone of a porphyry copper-gold system.
Emmerson believes that the recent assay results, combined with the previous rock chip results, have expanded the prospective footprint of the system to over 4 square kilometres.
The grid-based auger program also intersected altered monzonite intrusives and volcanics which are believed to be consistent with the host rocks of other Ordovician-aged porphyry systems in the belt.
Examples of these systems are Cadia-Ridgeway, mined by Newcrest Mining Limited (ASX:NCM) and containing 8.7 million tonnes of copper and 42 million ounces of gold, and China Molybdenum’s Northparkes deposit.
The company will use its geological and geophysical data to pinpoint the best parts of the mineralisation in its upcoming exploration work given that Whatling Hill has never been drill tested nor seen systematic exploration.
Pervasive epidote alteration in volcanic rocks