Zone 58N

Zone 58N


Phase: Exploration
Mine Type: Underground

Tags: biotite chalcopyrite dyke molybdenite scheelite sericite stockwork tonalit tourmaline

Gold Map

Canada, Ontario. From the town of Cochrane (population of approximately 5,000 residents), the Project is easily accessible by the Detour Lake Mine road, the northern extension of Highway 652. The first 151 km on Highway 652 is paved surface, followed by 34 km of well-maintained chipseal road to the mine site. Road access is available year-round. An airstrip built in 2021 provides access by air to the site. The closest major airport to the site is at Timmins, Ontario, approximately 61 km to the southeast.

Regional geology:

Abitibi greenstone belt

Abitibi greenstone belt of the Superior province of the Canadian Shield. The area consists mostly of felsic to mafic volcanic rocks of Archean age together with related dioritic sills which are concordant to the regional rock formations. These volcanic and intrusive rocks have generally been metamorphosed to the greenschist facies.

The Superior Province is the largest exposed Archean craton in the world and hosts several world class gold deposits. It has yielded nearly 300 million ounces of gold from hundreds of deposits since the beginning of the twentieth century. One prominent characteristic of all significant gold deposits in the Superior Province is their occurrence within or immediately adjacent to greenstone belts. Another characteristic is their occurrence within major tectonic zones which comprise a series of shear zones (Colvine et al., 1988). The Superior Province is divided into four major subprovince types (Card and Ciesielski, 1986): volcano-plutonic, plutonic, metasedimentary, and high metamorphic grade gneiss. The boundaries of these subprovinces are either major dextral, transcurrent, east-striking faults, or zones of structural and metamorphic transition.

The greenstone belts which host the gold deposits occur as east-north-easterly trending ribbon domains in the volcano-plutonic terrains. They typically consist of mafic to ultramafic and felsic metavolcanic rocks, interlayered with metasedimentary rocks. The supracrustal rocks were intruded by syn-volcanic plutons. Saturated and under saturated felsic to mafic igneous rocks intruded into the greenstone belts in late Archean.

The metamorphic grade of most of the present greenstone terrains ranges from sub-greenschist to greenschist facies in the centre, to lower amphibolite facies at the margin. Amphibolite facies contact metamorphic aureoles occur around intrusions into the greenstones (Jolly 1978, 1980) with the exception of the synvolcanic ones.

The Abitibi Greenstone Belt consists of east–west-trending synclines of felsic to ultramafic volcanic rocks. Intervening domes are cored by syn-volcanic tonalite and gabbro-diorite rocks and alternate with east–west-trending bands of late tectonic turbiditic and conglomeratic sedimentary rocks. Most of the volcanic and sedimentary strata dip vertically and are commonly bound by abrupt, east–west-trending faults with varied dips.

The stratigraphy of the Abitibi Greenstone Belt is subdivided into earlier volcanic-dominated episodes that include the Pacaud assemblage (2770–2736 Ma), the Deloro assemblage (2730–2724 Ma), the Stoughton-Roquemaure assemblage (2723–2720 Ma), the Kidd- Munro assemblage (2719–2711 Ma), the Tisdale assemblage (2710–2704 Ma), and the Blake River assemblage (2704–2695 Ma). These sequences are unconformably overlain by turbidites and calc-alkaline volcanic rocks of the Caopatina assemblage (ca. 2700 Ma) in the north and the Porcupine assemblage (2690–2685 Ma) in the south. These units in turn are unconformably overlain by coarse clastic and alkaline volcanic rocks of the Opemisca assemblage (ca. 2692 Ma) in the north and the Timiskaming assemblage (2676– 2670 Ma) in the south.

Regional Geology Plan

Deposit geology:

The Zone 58N mineralized system has been intersected over an east–west strike length of 450 m, from surface to a depth of 800 m, and the mineralized system remains open along strike and at depth. The mineralization extends from approximately 595,300E to 595,750E and 5,533,700N to 5,533,800N (UTM coordinates). The width of the mineralization is variable, ranging from 4 m to >100 m at the centre of the deposit. Infill drilling has demonstrated that the geology and mineralization dip subvertically at 75º to the south.

Gold mineralization in Zone 58N is within the southern portion of a feldspar porphyry intrusion, and characterized by intense brittle deformation and stockworks of quartz ± carbonate ± tourmaline veins with strong biotite–sericite–silica alteration. The thickness of the feldspar porphyry host rock can be >100 m and on average, mineralized lenses are 30 m wide. The feldspar porphyry intrusion narrows to the east and west near surface. Gold mineralization within Zone 58N is hosted by a swarm of plagioclase-phyric tonalitic dykes that intrude mafic rocks of the Deloro assemblage. The geometry of host dykes is controlled by a large (~1,000 m in diameter) cylindrically-shaped intermediate equigranular intrusion, resulting in emplacement at a slightly oblique angle to the strike of regional stratigraphy. The dyke rocks, and associated mineralization, reach a maximum width of 150 m near the southwestern portion of the intermediate intrusion, and taper along strike.

Cross Section, Zone 58N, Zone 75

Mineralization:

Visible gold is often present and occurs within coarse pyrite or as free gold within quartz. Sulphide mineralization associated with gold ranges from 0.5–5% pyrite with minor chalcopyrite, bismuth-tellurides, molybdenite and scheelite. Gold is found within and at the margins of quartz ± tourmaline ± carbonate stockwork-type veins that infill areas of brittle
deformation. Visible gold occurs in nearly every drill hole that intersects mineralization and is also present as micro-inclusions within pyrite grains, or intergrown with bismuth–tellurides.

Deposit types:

The deposit model for the 75 Zones is not firmly established. These mineralized lenses share characteristics with both syenite-associated oxidized intrusion-related deposits of the Kirkland Lake area (Robert, 2001) and the Sigma-Lamaque deposits of the southern Abitibi (Robert and Brown, 1986a, 1986b), the latter of which are thought to be associated with hydrothermal lode gold deposits.

Note:

Notes to accompany Mineral Resource tables:
1. The Mineral Resources have an effective date of 31 March, 2024. The Qualified Person for the estimates is Ms. Dyane Duquette, P.Geo., an Agnico Eagle employee.

2. Mineral Resources are reported in situ, exclusive of those Mineral Resources converted to Mineral Reserves. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. Mineral Resources are reported using the 2014 CIM Definition Standards.

3. Mineral Resources considered amenable to underground pit mining methods at Zone 58N were estimated assuming long-hole and transverse stoping methods. The estimates used a gold price of US1,300/oz, metallurgical recovery assumption of 97%, refining and transport costs of C$5/oz Au, average mining cost of C$75/t mined, process and tailings costs of C$9/t milled, general and administrative costs of C$11.50/t, assumed dilution average of 12%.

4. The estimate is reported using a cut-off grade of 2.2 g/t Au.

5. Estimates have been rounded in accordance with reporting guidelines. Totals may not sum due to rounding.

Mineral Resources (March 31, 2024)

Class Ore (ktonnes) Au grade (g/t) Au (kg) Au (oz * 1000)
Indicated 2868.00 5.80 16634.40 534.00
Inferred 973.00 4.35 4232.55 136.00

Source: