Vein-hosted gold mineralization in the Wilding Lake area, central Newfoundland: structural geology and vein evolution

Abstract

Crustal-scale fault zones in central Newfoundland are being recognized as significant gold-mineralized structures. In particular, a northeast-trending structural corridor in the eastern Dunnage Zone (Exploits subzone), delineated by the Rogerson Lake Conglomerate, contains highly prospective vein-hosted gold deposits. Such mineralized vein systems, exposed near Valentine Lake (Marathon Gold Corp.) and Wilding Lake (Antler Gold Inc.), are products of progressive Paleozoic deformation and fluid-pressure cycling along crustal-scale faults that cut the Late Silurian to Early Devonian Rogerson Lake Conglomerate and underlying Neoproterozoic basement rocks. Well exposed, gold-bearing quartz-vein systems in the Wilding Lake area reveal a kinematic history that involved a main phase of reverse sinistral shearing and subsequent transient phases of horizontal extension, oblique compression, and, at least locally, components of late dextral strike-slip. High-grade gold mineralization is associated with siderite-ankerite-sericite alteration of the host rocks, structurally controlled quartz-vein emplacement, and supergene alteration of pyrite and chalcopyrite. Gold-bearing vein sets contain quartz, pyrite, chalcopyrite, tourmaline, native gold, Ag-poor electrum, bismuth-silver-gold tellurides, rutile, and secondary goethite, malachite, and acanthite. Prospective gold exploration targets in the Wilding Lake area are Late Silurian feldspar porphyry and felsic volcanic rocks overlying the Rogerson Lake Conglomerate, as well as, rheologically favourable Neoproterozoic basement granitoids that may provide a setting similar to that at Valentine Lake.

Latest Silurian syntectonic sedimentation and magmatism and Early Devonian orogenic gold mineralization, central Newfoundland Appalachians, Canada: Setting, structure, lithogeochemistry, and high-precision U-Pb geochronology

“…The Rogerson Lake Conglomerate structural corridor hosts a highly prospective orogenic gold system, which includes an approximately four to five million ounce gold deposit in Neoproterozoic rocks at Valentine Lake (Lincoln et al, 2018) and numerous gold showings and prospects hosted within the conglomerate (e.g., Wilding Lake prospect; Figs. 1 and 2; Evans, 1996;Honsberger et al, 2019aHonsberger et al, , 2019bHonsberger et al, , 2020b. The gold-mineralized Neoproterozoic rocks at Valentine Lake include trondhjemite, tonalite, gabbro, and mafic dikes of the Valentine Lake Intrusive Suite (Fig.…”

“…In addition to gold mineralization, felsic volcanic rocks of the Wilding Lake prospect (Figs. 3C and 5B) also locally host galena, sphalerite, pyrite, and arsenopyrite-bearing, quartz-vein-related mineralization (Honsberger et al, 2020b).…”

Overview of age constraints for gold mineralization in central and western Newfoundland and new 40Ar/39Ar ages for muscovite from selected auriferous zones

“…422 Ma felsic subvolcanic and volcanic rocks in the footwall of the northeastern extension of the Valentine Lake shear zone (WL on Fig. 1; Honsberger et al 2019a;2019b;2020a;2020b;2022a). Overlapping ca.…”