GEOSCAN Search Results: Fastlink


TitlePaleoredox and lithogeochemical indicators of the environment of formation and genesis of the Monster River hyper-enriched black shale showing, Yukon
LicencePlease note the adoption of the Open Government Licence - Canada supersedes any previous licences.
AuthorGadd, M GORCID logo; Peter, J MORCID logo; Fraser, T A; Layton-Matthews, D
SourceTargeted Geoscience Initiative 5: volcanic- and sediment-hosted massive-sulfide deposit genesis and exploration methods; by Peter, J MORCID logo (ed.); Gadd, M GORCID logo (ed.); Geological Survey of Canada, Bulletin 617, 2022 p. 113-127, Open Access logo Open Access
PublisherNatural Resources Canada
Mediaon-line; digital
RelatedThis publication is contained in Targeted Geoscience Initiative 5: volcanic- and sediment-hosted massive-sulfide deposit genesis and exploration methods
RelatedNRCan photo(s) in this publication
File formatpdf
AreaYukon River; Ogilvie Mountains
Lat/Long WENS-140.5400 -140.5397 64.8350 64.8347
Subjectseconomic geology; geochemistry; sedimentology; stratigraphy; Science and Technology; Nature and Environment; Middle Devonian; mineral exploration; exploration methods; mineral deposits; sedimentary ore deposits; nickel; molybdenum; zinc; gold; ore mineral genesis; mineralization; ore controls; paleoenvironment; continental margins; marine environments; sea water geochemistry; depositional environment; sedimentation; lithogeochemistry; trace element analyses; major element analyses; geochemical anomalies; host rocks; bedrock geology; lithology; sedimentary rocks; shales; metals; sulphur; lithostratigraphy; cerium geochemistry; molybdenum geochemistry; uranium geochemistry; yttrium geochemistry; Monster River Showing; Yukon Block; Blackstone Trough; Canol Formation; Road River Group; platinum group elements; Phanerozoic; Paleozoic; Devonian
Illustrationslocation maps; geoscientific sketch maps; lithologic sections; photographs; tables; profiles; plots
ProgramTargeted Geoscience Initiative (TGI-5) Volcanic and sedimentary systems - volcanogenic massive sulphide ore systems
Released2022 01 27; 2022 11 17
AbstractNorthern Yukon hosts occurrences of Middle Devonian hyper-enriched black shale (HEBS) Ni-Mo-Zn-platinum-group element-Au-Re mineralization, including the Monster River showing in the Ogilvie Mountains. This mineralization has been documented predominantly in the Paleozoic Richardson trough; however, the Monster River showing is atypical, occurring within the Blackstone trough, more than 200 km to the west on the southern margin of the Yukon block. The ambient paleoredox conditions of the marine water column and sediments may be primary controlling factors in HEBS formation. We use major and trace element lithogeochemistry to better understand ambient paleoenvironmental redox conditions through the application of robust redox proxies to HEBS mineralization and host rocks. Uniformly negative Ce anomalies (0.6-0.9) indicate that the water column was predominantly suboxic throughout the deposition interval, even during HEBS mineralization. Although there is a strong terrigenous influence on the rare earth element-yttrium (REE-Y) abundances of the sedimentary rocks, superchondritic Y/Ho ratios (>27) indicate that seawater contributed REE-Y to the host rocks and HEBS. High (>10) authigenic Mo/U ratios indicate that a Fe-Mn particulate shuttle operated in the water column; this is corroborated by negative Ce anomalies and high Y/Ho ratios. The data indicate that metalliferous sedimentary rocks formed by hydrogenous metal enrichment (e.g. Ni, Mo, Pt) caused by ferromanganese oxyhydroxide particulate shuttling as chemical sediments; moreover, the REE- and Mo-based paleoenvironmental indicators suggest a complexly redox-stratified depositional environment with an abundant supply of metals, metalloids, and sulfur.
Summary(Plain Language Summary, not published)
The Targeted Geoscience Initiative (TGI) is a collaborative federal geoscience program that provides industry with the next generation of geoscience knowledge and innovative techniques to better detect buried mineral deposits, thereby reducing some of the risks of exploration. This contribution summarizes the results of a 5-year study of multiple mineral deposit types: polymetallic hyper-enriched black shale; sedimentary exhalative Pb-Zn; carbonate-hosted Pb-Zn, magnesite; fracture-controlled replacement Zn-Pb, rare-earth element-F-Ba; and volcanogenic massive sulfides. Studies employed field geology, combined with geochemical (lithogeochemistry, stable and radiogenic isotopes, fluid inclusions, and mineral chemistry) and geophysical (rock properties, magnetotelluric, and seismic) methods. Collectively, the research provides advanced genetic and exploration models for volcanic- and sedimentary-hosted base-metal deposits, together with new laboratory, geophysical, and field techniques.

Date modified: