| |
Ashley Jackson
Senior Resource Geologist – Fosterville Gold Mine
Tuesday 7th May, 2019
Nibblies from 6.30pm Presentation 6.50pm (approx.)
Basement on View
50 View St, Bendigo VIC 3550
The Fosterville Gold Mine, 100% owned by Kirkland Lake Gold Ltd is located in Central Victoria, approximately 20 kilometres east of Bendigo. The mine occurs within the Bendigo Tectonic Zone and is hosted within sub-greenschist facies Ordovician turbidites. Two primary gold mineralisation types occur within the deposit: disseminated sulphide mineralisation and quartz vein hosted visible-gold, with the latter becoming more prevalent since 2016 as mining has progressed deeper within the underground operation.
Structurally gold mineralisation is localised around faults straddling a syncline between the west-dipping Fosterville fault and the Phoenix splay. As mining and exploration has progressed to greater depths the geological knowledge of the Fosterville structural architecture has progressively grown. The present understanding of the structure and importantly the faulting includes the moderate-steep west-dipping Fosterville Fault, which has several en echelon arrays of footwall reverse faults that link across from a western anticline to a syncline in the east.
At greater depths within the mine (>850m) mineralisation is observed to undergo a rapid transformation from disseminated sulfide dominant to a quartz and visible-gold overprint of a pre-existing sulphide mineralized system with an observed increase in grade along gold bearing structures at increasing depth. This discovered change in mineralisation has resulted in Mineral Reserves that have more than tripled from December 2016 to December 2017, driven by an increasing grade profile with depth. The primary driver for the grade increase was the conversion of a portion of the Swan Mineral Resource to Reserve status that includes 1.16Moz at grade of 61.2g/t Au (almost two ounces per tonne), and underpins the Fosterville 1.7 Moz Reserve at a grade of 23.1g/t Au.
Fosterville Mineral Resources are estimated using the Ordinary Kriging method applied to wire framed sub-domains. The statistical population of the Swan is one of extremely high grades, but without the variability or the nugget normally found within high-grade gold bearing structures. As understanding of these high-grade visible-gold environments evolves with progressive drilling, mining, mapping and processing of the ore system, resource estimation techniques are improving to produce more reliable and robust Resource model estimates. This presentation will provide an overview of these techniques and methods being employed within the mine.
Ashley Jackson is a Geologist with over 25 years’ experience, holding a variety of roles in exploration,open pit and underground roles throughout Australia.
Mr Jackson has experience working in the Permian New England Orogen, Archaean greenstone, Archaean Hamersley basin, the Delamerian Tasman Orogen, including the Ordovician turbidites of Central Victoria.
Employed by a number of operations in NSW, Western Australia, Tasmania and currently Central Victoria, Mr Jackson has been working in Central Victorian Gold operations since 2011, and enjoys living in Bendigo with his family.
Mr Jackson joined the Fosterville Gold Mine in May 2012 as the Senior Resource Geologist and has been involved in the Resource estimation of the Fosterville Gold Operations during this time.
In his time at Fosterville, Mr Jackson has been intrinsic to the significant growth of the mine, with the recent discovery of the Eagle and Swan structures, which form the basis of the 1.7 Moz current Mineral Reserve.
Mr Jackson holds a Bachelor of Science (University of New England) and a Masters of Mineral Economics (Western Australian School of Mines), and is a member of the Australian Institut e of Geoscientists.
To support our Victorian Branch and ongoing future events we kindly ask for a small admission fee from our attendees:
AIG & AusIMM Members $10
Non-Members $15
Students Free
AIG Victoria will supply refreshments and nibblies.
Ben Jupp – bjupp@srk.com.au
Download the event flyer.
