Summary:
The Porcupine Complex deposits are classified as orogenic gold deposits as defined by Gebre-Mariam et al., (1995), Groves et al., (1998), and Goldfarb et al., (2001).
The Project is within the Kapuskasing structural zone of the Wawa sub-province, and Abitibi sub-province of the Archean Superior Craton.
Two major deformation zones pass through the Abitibi sub-province near Timmins, the Porcupine–Destor deformation zone, and the Larder Lake- Cadillac deformation zone.
Gold mineralization is considered to be generally late in the evolution of the Abitibi subprovince. Deposits are juxtaposed along the Porcupine–Destor and Larder Lake– Cadillac deformation zones.
Mineralization in the Timmins area primarily consists of networks of steeply to moderately dipping fault-fill quartz-carbonate ± tourmaline ± pyrite veins and associated extensional, variably deformed, shallowly to moderately dipping arrays of sigmoidal veins hosted in highly carbonatized and sericitized rocks.
The Mineral Resource estimates for the Borden, Dome, Hoyle Pond, and Pamour deposits.
Borden
Mineralization has been defined over about 5.8 km of strike, and remains open in the down-plunge direction. The deposit displays a consistent northeast dip and, locally, a shallow southeast plunge. The mineralized zone can be as thick as 120 m, and has been drill tested to about 1,100 m vertical depth.
The mineralization generally consists of low to moderate grade gold with minor silver concentrations and is typically characterised by a higher-grade core surrounded by a lower-grade envelope.
The west–northwest portion of the deposit is generally lower grade with some higher-grade pods, consisting of disseminated sulphides with localised silicification. It typically lacks strong quartz veining. This lower-grade mineralization rarely hosts visible gold grains.
The higher-grade zone contains abundant quartz and less abundant pyrite and pyrrhotite than the lower-grade area. Free gold is visible at the contacts between deformed quartz veins and brecciated lithologies and also within the groundmass of the deformed quartz veins.
Dome
The mined-out stopes at the Dome mine define a mineralized area that was about 280 m northeast in strike length on plan view, 20–60 m wide, and dipped steeply to the north. Parallel mineralized zones, when projected to surface, cover about 800 m wide and 1,500 m long.
The Dome pit, which is mined-out, is 930 m wide, slightly elongate to the northeast for a strike extent of 940 m, and reached a total depth of 340 m.
All mineralization at the Dome mine is present between these two structures and is commonly associated with lesser reverse shears occupied by ankerite veins or extensional veins acting as accommodation structures.
Gold at the Dome mine occurs primarily as native gold in quartz or ankerite veins. Gold tellurides have been recognized, but constitute a very minor source of the total gold production. Silver is recovered as a by-product.
Sulphides are present in all mineralization types, and average about 2–3%. Pyrites with lesser pyrrhotite are the dominant sulphides; chalcopyrite, sphalerite, and galena are also found locally.
Hollinger
Mineralization at Hollinger has been defined over 1.6 km of northeast strike, generally plunges moderately to the northeast and was mined to depths of 1670 m below surface. The Hollinger mineralization connects with that defined at the McIntyre mine which has been extracted to depths of over 2700 m, approximately 500 m to the northeast. The overall strike of both the Hollinger and McIntyre vein systems has been defined over more than 3.1 km of strike.
Mineralization remains open at depth and parallel veins likely persist. Veins have individual widths of less than 1 m to approximately 20 m and zones of multiple parallel veins exists to over 100 m widths at lower levels in the former operations. Near surface, zones of parallel veins can reach over 300 m in width.
Mineralization is spatially related to the Pearl Lake porphyry and to the Hollinger Main Fault, which is a high-strain zone of lineation and constrictional strain development with no identified offsets.
The principal mineralization type consists of massive, white quartz veins and stringers with well-developed pyrite-carbonate and ankerite-sericite alteration envelopes. Mineralized wall rock contains gold intimately associated with pyrite. Minor free gold commonly occurs along the vein margins.
Vein systems are present as en-echelon veins, quartz veins with branching stringers and individual veins. Gold may be confined to quartz in some veins, but in others, it is associated with pyrite in the adjacent wall rock.
Hoyle Pond
Mineralization at Hoyle Pond has been defined along an 850 m northeasterly strike near surface, and has been mined and drill defined down plunge at about a 40º dip for over 3 km. Currently, mine infrastructure is established to 199 0m below surface and Mineral Resources are drill defined to 2500 m below surface. Veins vary from <0.1–3 m in thickness, but are thicker where later generations of quartz have further dilated the vein. Numerous parallel veins occur throughout the mine system, often allowing for wider zones to be mined.
Most of the gold mineralization at Hoyle Pond occurs as coarse free gold in white to grey–white quartz shear veins with a variable ankerite, tourmaline, pyrite, and arsenopyrite content. The Hoyle Pond Main Zone and 1060 Zone occur on opposite.
sides of the ultramafic core. These zones consist of northeast-striking, subvertical quartz veins that are folded on a small scale. Flat-lying veins (7 veins, VAZ veins) are found throughout the deposit area. The quartz veins are generally boudinaged.
Pamour
Mineralization at Pamour has been drill-defined over a 3.2 km northeast strike. The zone plunges about 30º to the northeast and has been mined to a depth of about 850 m.
Existing drilling suggests zone extensions below the 850 m depth is possible at both the southwest and northeast ends of the existing mining infrastructure. A parallel zone exists 500m to the north of the main Pamour mineralization which shows similar characteristics and has a 1.5 km strike length.
Gold occurs in two principal modes:
• Free gold associated with narrow, quartz–ankerite extension veins with associated traces of sphalerite, galena, and locally arsenopyrite. Pyrite and pyrrhotite also occur within the quartz veins but are more commonly found as disseminated grains in the bleached and altered wall rock;
• Disseminated pyrite–gold alteration halo around the sheeted quartz veinlets and stockworks. In general, an increase in the pyrrhotite/pyrite ratio is indicative of an increase in the gold content. Locally, in order of decreasing abundance, arsenopyrite, sphalerite and galena may occur in minor amounts.