The Thorn Project hosts a district scale Paleocene-Cretaceous-Triassic-Jurassic, volcano-plutonic complex and related sedimentary units with several styles of mineralization related to porphyry and epithermal environments.
THORN GOLD-COPPER-SILVER PROJECT
Geology at the Thorn Property is defined by volcanic and sedimentary rocks of the Stikine tectonostratigraphic terrane intruded by Late Cretaceous to Eocene volcanoplutonic rocks. In this area, the Stikine arc is composed of the Stuhini and Laberge Groups. The Stuhini Group is a Late Triassic island arc sequence comprised of massive submarine andesite and pillow basalts overlain by the Sinwa Formation, which are deep submarine clastic sedimentary rocks that shallow upwards, with increasing occurrences of limestone beds upwards. The Laberge Group is Early to Middle Jurassic in age and unconformably overlies the Stuhini Group. It is composed of 3-5 km of calcareous clastic sediments, including sandstone, conglomerate and shale. Multiple stages of subduction-related magmatism were emplaced at the Thorn Property from the Paleocene-Eocene, Cretaceous, Triassic and Jurassic. At the Outlaw Zone, Jurassic-aged rhyodacite dykes are related to gold mineralization. The Golden Bear Mine gold mineralization was Jurassic in age, however, mineralization at Camp Creek is Cretaceous in age.
Geological and geochemical work completed on the Thorn Project to date, has outlined several significant copper-gold porphyry targets across the property, in addition to epithermal mineralization and intrusion-related mineralization.
- Mineralization at the Camp Creek is within a 2km by 1km area has been the main focus of drilling by Brixton Metals thus far. However, it was only in 2019 that drilling was deep enough to test the blind porphyry. Deeper drilling in 2019 and 2020 encountered porphyry-style veining beginning at depths of roughly 300m-500m. THN20-181 returned 439m of mineralized porphyry Cu-Au-Ag-Mo. Further drilling is needed to determine the extent of this mineralization. The 2021 plan is to drill test the Camp Creek porphyry in several locations, starting with extending hole 181 to greater depths.
- The Oban zone is a porphyry-related diatreme breccia where polymetallic (Au-Ag-Cu-Pb-Zn) mineralization is hosted in the breccia matrix. Subrounded clasts are composed mostly of quartz diorite porphyry, some of which contain mineralized porphyry-style veining. Hole THN19-150 drill tested the diatreme to 829m depth, intersecting 0.57g/t Au, 0.24% Cu, 43.18g/t Ag, 0.55% Zn and 0.28% Pb over 554.7m (97.00-651.70m).
- The Glenfiddich zone consist of high-sulphidation veins and silica-flooded breccia hosting high Cu-Ag-Au. Intense silicification with vuggy texture is exposed on several outcrops at surface and is host to pyrite, tetrahedrite and enargite. Hole THN13-121 drilled 10.6% Cu, 583 g/t Ag, 2.5 g/t Au over a true width of 1.1m.
- The Talisker zone is defined by a northeast striking high sulphidation vein corridor. It has strike length of 600 m and is open to the northeast. Disseminated and vein-hosted pyrite and sulphosalts with strong sericite alteration yield significant Au-Cu-Ag values. The best Talisker hole, THN11-51, returned 48.78m of 1.42 g/t Au, 19.2 g/t Ag, and 0.25% Cu.
The Outlaw Zone is composed of sediment-hosted (siltstone-greywacke-argillite-carbonates) Au-Ag related to pyrite and pyrrhotite veins, and stratiform disseminated to semi-massive py-po. Mineralized horizons may be related to the Jurassic-aged felsic dykes, suggesting the mineralization is intrusion-related. Gold-in-soil anomaly is greater than 4 km, with a gold horizon in the central part of the target that extends an east-west trend for 600m through drilling. Hole THN14-128, drilled in the Central Outlaw area, returned 59.65m of 1.15 g/t Au. Surface rocks samples have returned up to 22.9 g/t Au from East Outlaw and 68.8 g/t Au from West Outlaw. The goal for 2021 is to extend the Central Zone to the East Zone for a 2 kilometer strike through channel sampling and drilling.
Geology at Trapper is predominantly volcanic and volcaniclastic rocks of the Upper Triassic Stuhini group, which are intruded by feldspar-phyric diorite sills thought to be part of the Thorn Magmatic Suite. Porphyritic dykes crosscut both rock groups. These porphyritic dykes are often elevated in Au-Cu-Ag mineralization. Gold mineralization is associated with structurally-controlled quartz-carbonate stockwork and epithermal veins that host sulphides (pyrite, galena, sphalerite), and rare occurrences of visible gold. As of 2011, 42 diamond drillholes have been drilled in the Trapper area and hole TG-11-11 returned 32.64m of 1.78 g/t Au, including 0.41m of 92.8 g/t Au. Rock samples collected in 2020 included high-grade assays of 47.0 g/t Au, 41.6 g/t Au, and 31.9 g/t Au, outlining a new drill-ready gold target. The gold mineralization is associated with copper and silver, with values up to 5.2% Cu and 1,490 g/t Ag.
Metla is a new 20km copper-gold porphyry anomaly within the Thorn Project. Major rock units at Metla include sedimentary and mafic- to ultramafic-intrusive rocks of the Stikine assemblage, volcanic and volcaniclastic rocks of the Stuhini Group, Late Cretaceous to Paleocene felsic intrusive rocks, and hydrothermal breccia dykes that crosscut all of the previous units. Several distinct styles of mineralization occur in the Metla area. Massive pyrite, chalcopyrite and sphalerite are hosted in the hydrothermal breccia and porphyry, along with bornite, chalcopyrite and chalcocite. Rock samples collected have returned up to 62.7 g/t Au and 4.54% Cu. A 1989 trench by Cominco returned 9m of 4.6 g/t Au. A satellite camp is planned for Metla to define drill targets through additional geochemistry, mapping and geophysical surveys.
The East Target is a 10km by 10km area where geology is dominated by Middle to Late Triassic quartz diorite and granodiorite intrusive rocks, with windows of Stuhini Group volcanic rocks. There are anomalous copper values throughout the area, across a 600m trend on surface. Copper mineralization is commonly observed as vein-hosted. Previous drilling did not target the area hosting the most anomalous samples. Surface rock samples have returned up to 5.15% Cu and 145 g/t Ag.
The West target is primarily a copper target. Geology at the West Target is composed of volcanic rocks of the Stuhini Group, and argillite and conglomerate of the Laberge Group. The lower volcanic and sedimentary rocks are cut by granitic intrusions, migmatitic metamorphic rocks, and volcaniclastic rocks. Mineralization is vein-hosted and disseminated, with porphyry-style quartz-pyrite-chalcopyrite veins in the intrusive and volcanic rocks. Rock sampling in 2020 returned up to 4.27% Cu.
The Central Target geology is dominated by plutonic rocks, with Middle to Late Triassic quartz-diorite intruded by granitic intrusive rocks of the Sloko Suite. At surface there are stockwork quartz-molybdenite-chalcopyrite veins, as well as several historic drillholes. East-west trending sheeted veins, up to 1.5m thick, contain molybdenite, which is locally massive.
Geology at the South Target includes greenstones of the Whitewater Metamorphic Complex, coarse clastic sedimentary rocks of the Stikine Assemblage and Late Triassic quartz diorite intrusive rocks. Mineralization includes vein-hosted chalcopyrite and disseminate pyrite and chalcopyrite. Further geochemical surveys, prospecting and mapping are planned.
The GoldBee Target is the southern extension of the Golden Bear Mine trend. Gold mineralization is structurally controlled and hosted within sediments. Geochemical surveys and prospecting are planned.
Mr. Gary R. Thompson, P.Geo., Chairman, President and CEO of Brixton, is the QP who approved the scientific and technical information on this website.