|Title||Evolution of the Selwyn Basin region, Sheldon Lake and Tay River map areas, central Yukon|
|Author||Gordey, S P|
|Source||Geological Survey of Canada, Bulletin 599, 2013, 190 pages (5 sheets), https://doi.org/10.4095/293034|
|Publisher||Natural Resources Canada|
|Map Info.||geological, structural, lithological, 1:250,000|
|Map Info.||geological, structural, lithological, 1:100,000|
|Projection||Universal Transverse Mercator Projection (NAD83)|
|Related||This publication contains the following
|File format||readme /
|Area||Selwyn Basin; Sheldon Lake; Tay River; Pelly River; Prevost River; Jackfish Lake; Ross River; South MacMillan River|
|Lat/Long WENS||-134.0000 -130.0000 63.0000 62.0000|
|Subjects||stratigraphy; structural geology; metallic minerals; sedimentology; basins; basin evolution; sedimentary basins; bedrock geology; structural features; lithology; mineral occurrences; faults; faults,
thrust; folds; lineations; structural features; stratigraphic analyses; stratigraphic correlations; igneous rocks; volcanic rocks; sedimentary rocks; sandstones; limestones; shales; cherts; siltstones; turbidite sedimentation; turbidites;
conglomerates; clastics; deformation; granites; basalts; Selwyn Basin; McEvoy Platform; Slide Mountain Terrane; Yukon-Tanana Terrane; Selwyn Plutonic Suite; Jones Lake Formation; Mount Christie Formation; Tay Formation; Earn Group; Prevost Formation;
Portrait Lake Formation; Road River Group; Rabbitkettle Formation; Gull Lake Formation; Hyland Group; Yusezyu Formation; Mesozoic; Paleozoic; Cretaceous; Triassic; Permian; Carboniferous; Mississippian; Pennsylvanian; Devonian; Ordovician; Silurian;
Cambrian; Proterozoic; Precambrian|
|Illustrations||location maps; photographs; stratigraphic columns; ternary diagrams; tables; Concordia diagrams; cross-sections|
|Program||GEM Tri-Territorial Information Management & databases (Tri-Territorial Bedrock Framework), GEM: Geo-mapping for Energy and Minerals|
|Links||Metadata - Métadonnées|
|Released||2014 02 12|
|Abstract||Late Precambrian to Cretaceous, weakly metamorphosed strata of the ancestral North American margin comprise four sequences:|
Upper Precambrian to Middle Devonian (more than 3000 m) turbiditic
sandstone, deep-water limestone, shale, and chert (Selwyn Basin), flanked southwesterly in the Siluro-Devonian by shallow-water carbonate and clastic sediments (McEvoy Platform). Early Cambrian pelite hosts deposits of stratiform lead-zinc.
Devonian and Mississippian turbiditic quartz-chert sandstone and chert-pebble conglomerate (2000 m) shed from elevated fault blocks of Selwyn Basin strata. Stratiform barite occurs within siliceous shale of mid- to Upper Devonian
Mississippian to Triassic shale, chert, limestone, minor sandstone, and siltstone (1700 m) deposited on a shallow-marine shelf; and Lower Cretaceous clastic sediments (120+ m) derived from Jura-Cretaceous deformation and uplift. Regional
Jura-Cretaceous deformation formed décollement style, northwest-trending folds and large, shallow-dipping thrust faults. Incompetent Cambro-Ordovician to Lower Devonian strata are complexly deformed above a regional flat-lying detachment. Deformation
was accompanied by obduction of oceanic ultramafite, basalt, chert, and carbonate (Slide Mountain Terrane) as well as siliceous mylonite and schist (Yukon-Tanana Terrane).
Granitic intrusions of the mid-Cretaceous (100 Ma) Selwyn Plutonic Suite
crosscut regional structure and are responsible for small skarn and base-metal vein deposits. Coeval pyroclastic rocks of the South Fork volcanics are preserved within huge calderas.
Cretaceous-Tertiary dextral slip along Tintina Fault has offset
geological elements at least 430 km and formed pull-apart basins along and near the fault. Eocene fill of fluvial clastic and bimodal volcanic rocks host epithermal precious-metal veins.