Evolution of the Hazelton arc near Terrace, British Columbia: stratigraphic, geochronological, and geochemical constraints on a Late Triassic – Early Jurassic arc and Cu–Au porphyry belt

Understanding the development of island arcs that accreted to the North American craton is critical to deciphering the complex geological history of the Canadian Cordillera. In the case of the Hazelton arc (part of the Stikine terrane, or Stikinia) in northwestern British Columbia, understanding arc evolution also bears on the formation of spatially associated porphyry Cu–Au, epithermal, and volcanogenic massive sulfide deposits. The Hazelton Group is a regionally extensive, long-lived, and exceptionally thick Upper Triassic to Middle Jurassic volcano-sedimentary succession considered to record a successor arc that was built upon the Paleozoic and Triassic Stikine and Stuhini arcs. In central Stikinia, near Terrace, British Columbia, the lower Hazelton Group (Telkwa Formation) comprises three volcanic-intrusive complexes (Mt. Henderson, Mt. O’Brien, and Kitselas) that, at their thickest, constitute almost 16 km of volcanic stratigraphy. Basal Telkwa Formation conglomerates and volcanic rocks were deposite...