The geology of the Khayyam and Stumble-On deposits, Prince of Wales Island, Alaska
type: CreativeWork
description: The Khayyam and Stumble-On deposits are stratiform copper-zinc-gold-silver massive sulfide deposits within the late Proterozoic(?) to pre-Middle Ordovician Wales Group, a metamorphosed volcanic arc complex within the Alexander tectonostratigraphic terrain. These massive sulfide deposits are interbedded with schist layers of siliceous, felsic, intermediate and mafic composition from 1 m to 30 m thick. Within the study area, these strata strike N 70° - 80° W and dip from 70° S to 70° N. Whole rock geochemistry of five samples indicate that the host rocks are metamorphosed, high-sodium low-potassium tholeiitic to calc-alkalic volcanic rocks. Electron microprobe energy dispersive analysis and petrographic observations show that fine-grained mafic schist contains plagioclase with compositions ranging from An₁₉ to An₃₁, and amphiboles that plot in the compositional fields of calcic ferro-and magnesio-hornblendes. These mineral compositions indicate metamorphism to the lower amphibolite facies. The Khayyam deposit was mined from 1901 to 1907, when approximately 250,000 metric tons of ore, including 3.2 million kg copper, 36,600 g gold and 48,600 g silver were recovered. It is comprised of multiple stacked sulfide lenses up to 80 m long and 7 m thick. Base and precious metal zonation is apparent in the Khayyam mine area, with copper, gold and silver concentrated along the main ore horizon; zinc is in relative abundance along the main ore horizon's western edge. The Stumble-On deposit, 2 km to the east, is a single sulfide lens greater than 170 m long and up to 2 m thick, with a local parting of schist of intermediate composition. A ground VLF-EM survey in the Stumble-On mine area indicates that the orebody may continue along strike in the subsurface to the east. Metal ratio plots show that the relative abundances of copper and gold within this sulfide lens appear to increase in the same direction. Correlation coefficients calculated for massive sulfide samples taken from bo…
abstract: The Khayyam and Stumble-On deposits are stratiform copper-zinc-gold-silver massive sulfide deposits within the late Proterozoic(?) to pre-Middle Ordovician Wales Group, a metamorphosed volcanic arc complex within the Alexander tectonostratigraphic terrain. These massive sulfide deposits are interbedded with schist layers of siliceous, felsic, intermediate and mafic composition from 1 m to 30 m thick. Within the study area, these strata strike N 70° - 80° W and dip from 70° S to 70° N. Whole rock geochemistry of five samples indicate that the host rocks are metamorphosed, high-sodium low-potassium tholeiitic to calc-alkalic volcanic rocks. Electron microprobe energy dispersive analysis and petrographic observations show that fine-grained mafic schist contains plagioclase with compositions ranging from An₁₉ to An₃₁, and amphiboles that plot in the compositional fields of calcic ferro-and magnesio-hornblendes. These mineral compositions indicate metamorphism to the lower amphibolite facies. The Khayyam deposit was mined from 1901 to 1907, when approximately 250,000 metric tons of ore, including 3.2 million kg copper, 36,600 g gold and 48,600 g silver were recovered. It is comprised of multiple stacked sulfide lenses up to 80 m long and 7 m thick. Base and precious metal zonation is apparent in the Khayyam mine area, with copper, gold and silver concentrated along the main ore horizon; zinc is in relative abundance along the main ore horizon's western edge. The Stumble-On deposit, 2 km to the east, is a single sulfide lens greater than 170 m long and up to 2 m thick, with a local parting of schist of intermediate composition. A ground VLF-EM survey in the Stumble-On mine area indicates that the orebody may continue along strike in the subsurface to the east. Metal ratio plots show that the relative abundances of copper and gold within this sulfide lens appear to increase in the same direction. Correlation coefficients calculated for massive sulfide samples taken from bo…
author: Barrie, Charles Prescott
language: en
keywords: Prince of Wales Island Alaska geology, Alaska geology, Prince of Wales Island geology, Prince of Wales Island sulfide deposits, Prince of Wales Island ore deposits, Khayyam geology, Stumble-On geology, Alaska sulfide deposits, Alaska metamorphosed rock, Alaska volcanic rock, Alaska petrography, Alaska porphyroblasts
date published: 1984
date modified: 2026-07-27T21:19:19Z
provider: Texas Digital Library
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Texas Digital Library

PropertyValue
property ID: Handle
value: https://hdl.handle.net/2152/125411

PropertyValue
property ID: DOI
value: 10.26153/tsw/51977