Mina Lake
Location, Access, Description
The Mina Lake property is located in the Jamesie MRC of the Nord-Du-Quebec administrative region, about 45 km southeast of Waswanipi (Qc) and 45 km southwest of Chibougamau (Qc). It is composed of 5 contiguous mining titles totalling 279 ha northeast of Mina lake, in NTS 32G11, Eeyou-Istchee James Bay Territory. These titles are fully owned by Globex mining entreprises inc. The property is accessible by road from Chapais (Qc), driving about 50 km to the south on gravel roads.
Main commodities can be found in Chapais / Chibougamau regarding contractors, equipment rental, as well as sleep and food accommodation of remote workers.
Topography is quite flat on the property, with elevations comprised between 370 and 380 metres above sea level. North half is covered with black spruce and jack pine, while south half is swampier and dominated by peatlands and alders. Outcrops can be observed essentially in the north half of the property. Several streams run through the property and connect to the Mina lake to the south-west. Limited exploration can be done during summer months due to swampy grounds, but every part of the property is accessible with machinery during winter months as streams and lakes are iced.
Geology and Mineralization
Regional Settings
The Mina Lake property is located in the northeast part of the Archean Greenstone Belt of the Abitibi Sub-province, in the Superior Province of the Canadian Shield. This area belongs to the Northern Volcanic Zone of Chown et al (1992) which exposes the eldest rocks of the Abitibi Sub-province (2,730 – 2,710 Ma).
The property is part of the southern band of the Chibougamau-Matagami belt, so called the Caopatina-Quévillon greenstone belt (MB 90-01). The region comprises a synclinal structure (Druillettes synclinal) and an anticlinal structure (Opawica anticline) both oriented N090° to N100° (Figure 2). The heart of the anticline is occupied by the Opawica Pluto, a tonalitic (syn-volcanic) pre-kinematic age. The Druillettes synclinal is made up of sequences of volcano-sedimentary rocks from the Obatogamau and Caopatina Formations. It is bordered to the northwest by a mylonitic band associated with the Guercheville fault which lies approximately 1.3 kilometres north of the property. To the north, the synclinal of Druillettes is bordered by the gneiss of the Lapparent Complex, to the northeast by the tonalitic syn-tectonic pluto of Rachel and to the west by the post-tectonic La Ronde Pluto (MB 90-01). The Obatogamau and Caopatina Formations are located at the very base of the 1st volcanic cycle of the Chapais-Chibougamau area (MM 89-03).
Rocks from the Chibougamau-Matagami greenstone belt were deformed and metamorphosed by two orogens. The earlier Kenorean orogen (2800-2600 Ma), was a three phase regional deformation that resulted in large E-W domes & basins structures and associated E-W, SE and NE regional fault systems. The Grenville orogen (1300-1000 Ma), on the other hand is responsible for the NNE regional fault system visible on figure 2.
Several intrusions are present in the surroundings of the Mina Lake property. The Rachel pluton is a syntectonic tonalite, located to the north of the property. The La Ronde pluton is a syntectonic monzonite, located to the west. The Opawica River Complex is similar to the Doré Lake anorthositic Complex and consists of a banded intrusion with an anorthositic level at its base, surmounted by a 900 metres thick gabbro-ferropyroxenite level. The Opawica Pluto is a 500 m to 3.5 km wide intrusion lying in the heart of the Opawica River Complex. It’s composed of tonalite, quartz-diorite and QFP dykes (Midra, 1989).
The metamorphic grade of the Caopatina-Quévillon belt is of greenshist facies, locally reaching the amphibolites facies near the Grenville front and along deformational corridors and intrusion margins.
Property Geology
The Mina Lake property is located over a section of basalts from the Obatogamau Formation (Figure 3), mostly composed of massive and pillowed basalts of tholeiitic affinity. 3 to 20% plagioclase feldspar megacrysts can be observed locally (MB 90-01). In this area, the basalts are squeezed between the Rachel pluton to the NE and the La Ronde pluton to the SE. Mafic volcanoclastites, gabbro sills, wacke horizons and massive felsic volcanics are also observed in intercalations within basalts of the Obatogamau formation.
The property is located over the Druillettes syncline which is overfolded to the north and plunges to the east. The Guercheville fault zone crosses the property in a northwest/southeast direction and corresponds to a series of parallel shear zones limited to a corridor less than 1 km wide. This structure is parallel to the regional schistosity and possesses a distinct magnetic signature, marked by the presence of numerous Input anomalies (Figure 3).
The schistosity on the Mina Lake property is sub-vertical and SE-oriented (MB 90-01). In this area, the stratigraphy and regional schistosity of the volcanics are parallel, which is generally the case in the Obatogamau Formation. Metamorphism is at the greenschists grade. More details on the Mina Lake property are presented in Amrhar & Rioux (2017 – GM 70968).
Metallogeny
The mining district of Chapais-Chibougamau has for long been known as “the shear zone hosted deposits region” and produced approximately 1.2M tons of copper, 3.7M oz of gold, 20.9M oz of silver, 115 000 kg of zinc and 4000 kg of lead (MB-96-14). The region is host to several types of deposits and showings within a wide variety of geological context. The Caopatica Segment is host of the principal gold
producing mine in the district, the Joe Mann mine. It is also host of two past producing gold deposits (Lac Shortt and Lac Bachelor mines), and of one past producing Zn-Pb-Ag deposit, the Coniagas mine.
Following Brochu & Hamel-Hébert (BG 2023-06), deposit types that are the most likely to be found in this area include 1) Orogenic Gold associated to the Guercheville shear corridor, 2) VMS or vein-type synvolcanic mineralization hosted in felsic or mafic volcanics, associated with positive Mag and EM anomalies (Fenton deposit style), and 3) Gold associated with hydrothermalism of felsic to intermediate late intrusives (Drouet Pluto).
The Guercheville corridor represents the first-class metallotect for both Au and base metals mineralization in the area of the property. This regional structure hosts several showings and deposits, the most important one being the former Joe Mann mine located some 65 kilometres ESE of the Mina Lake property, with a historical production of 4,289,221 tonnes of ore at 7.56 g/t Au and 0.23% Cu (GM 70966).
Historical work by both the Quebec Ministry and private companies listed 3 gold showings and 1 Cu showing within the property boundaries : 1) The Lac Mina-Guercheville showing exposes about 60% qz-carb veins associated to carbonate-chlorite-sericite alteration in sheared basalts of Obatogamau. Assays up to 20.57 g/t Au returned in historical grab samples (GM 40469) ; 2) the Ex-In showing exposes up to 10% sulphides (Py-Po-Asp) disseminated in quartz veins and breccias hosted in chloritic schists. Assays up to 1.3 g/t Au over 1.0 m were obtained historically in channel-sampling (GM 53325) ; 3) the Papillon showing is composed of semi-massive sulphides (30% Py) hosted in mudrocks interbedded with iron formations of the Caopatina Formation. Decimetric milky quartz veins affect both hostrocks and semi-massive sulphides. Assays up to 686 ppb Au have been observed historically on grab samples (BG 2023-06).
Works of the Quebec Ministry of Energy and Natural Resources (BG 2023-06) recently defined several favorable potential horizons for both Au and Cu mineralizations within the Obatogamau basalts. On figure 2, one of these Cu-favorable horizons is identified directly on the Mina Lake property.
HISTORY
The first work reported on the property began in 1957 with the discovery of the Lac Mina-Guercheville showing where a grab sample returned 17.14 g/t Au (0.5 oz/t) in sheared basalts (GM 47661).
Several mining companies have successively undertaken various exploration work including geological surveys, ground and airborne geophysics (Mag, EM), trenching, stripping, and channel-sampling, but no drilling has ever been implanted on the Mina Lake property. More details are given in Amrhar & Rioux (2018 – GM 70968).
Among the most recent works on the property, those of Native Exploration Services Reg’d (NES) are of particular interest. In 2014 the company carried-out both ground Mag and HLEM-MaxMin geophysical surveys on the Mina Lake property (GM 69041 & 69440) which highlighted several strong conductors, some of which are related, at least partially, to magnetic horizons and Input anomalies (Figure 4). Rock stripping and channel-sampling was then carried-out by NES in 2015-2016 in order to test the best geophysical anomalies. Trench #4000W – 1750N located on Globex’s Mina Lake property revealed anomalies up to 11,234 ppm Cu over 1.0 m and up to 634 ppb Au over 1.0 m in sheared felsic tuffs injected with QFP dykes (GM 70081).
In 2016, NES implanted two (2) DDH just east of the Mina Lake property of Globex in order to investigate a favourable (VMS) volcanogenic massive sulphide environment identified within trench #3200W – 2125N and also test the gold potential associated with porphyries (GM 70080). Assays up to 0.28 g/t Au, 1 033 ppm Cu and 3 485 ppm Zn over 1.5 metre returned from graphitic tuffs mineralized with semi-massive pyrrhotite ±chalcopyrite in hole SB-16-01, and up to 1.26 g/t Au, 189 ppm Cu and 78 ppm Zn over 1.0 metre in felsic tuffs from hole SB-16-02.
In 2017, Globex carried-out both geological mapping and channel-sampling on the NES trench (GM 70968). A total of 21 channel-samples and 4 grab samples were collected and returned up to 13 500 ppm Cu (grab sample) in oxidized sheared mafic volcanics and up to 346 ppb Au over 1.0 metre (channel sample) in chloritized and ankeritized sheared mafic volcanics (Figure 5).
In 2021, Nimsken Corporation carried-out ground Mag and IP surveys on the Mina Gold property (GM 72956). Numerous IP axis were highlighted in strike with Globex’s Mina Lake property, some of which being related to both positive Mag / MaxMin / Input anomalies (Figure 6).
In 2022, Globex mandated NOVATEM to survey the Mina Lake property with new Very-High Resolution Mag (GM 72868).
Resources and Potential
Numerous Gold (Au) and copper (Cu) showings have been uncovered historically in the vicinity of the Mina Lake property, which sets a strongly favorable area for both gold and base metals exploration. This favorability is due to both the existence of regional structures as the Opawica anticline, the Druillettes syncline and the Guercheville shear corridor, and large plutos which brought both heat and metallic fluids.
The presence of both the Guercheville shear corridor and several gold showings on the property, as well as numerous coincident Mag / EM / IP anomalies immediately east of the property are some major reasons to actively pursue the exploration of the Mina Lake property. No DDH has ever been drilled on the Mina Lake property, despite encouraging results on historical DDHs east of the property.
Further work should include new geophysical surveys (EM and IP) in order to highlight coincident anomalies with the recent NOVATEM Mag data. Depending on the results, mechanical stripping and DDH should be necessary.