[Named by Leach (1910, in Canada Geological Survey Summary Report, 1909, p.64) for series of volcanic rocks and fossiliferous sandstones and shales on Telkwa River and Hudson Bay Mountains to north of Hazelton, Skeena River district, British Columbia.] Beds in Hyder district, southeastern AK, are assigned to Hazelton group because of their lithologic similarity to group in British Columbia and because of similar structural relations to Coast Range intrusive rocks of Jurassic or Cretaceous age. Group is divided into predominantly greenstone unit and graywacke-slaty argillite unit (both shown separately on geologic map of Hyder district). Is of probable Jurassic(?) age based on age of group in Canada where Jurassic fossils were found in upper part.

Source: GNU records (USGS DDS-6; Menlo GNULEX).