GEOSCAN, résultats de la recherche


TitreGlacial history and drift prospecting in the Canadian Cordillera: recent developments
AuteurPlouffe, A; Ferbey, T; Levson, V M; Bond, J
SourceProspectors and Developers Association Convention (PDAC), abstracts volume; par Prospectors and Developers Association of Canada; 2012.
Séries alt.Secteur des sciences de la Terre, Contribution externe 20110284
RéunionProspectors and Developers Association Convention (PDAC); Toronto, ON; CA; mars 4-8, 2012
Référence reliéeCette publication est reliée Plouffe, A; Ferbey, T; Levson, V M; Bond, J D; (2012). Glacial history and drift prospecting in the Canadian Cordillera: recent developments, Commission géologique du Canada, Dossier public 7261
ProvinceColombie-Britannique; Yukon
SNRC95C; 95D; 95E; 105; 115; 116B/01; 116B/02; 116B/03; 116B/04; 82F/03; 82E/13; 82L/04; 82L/05; 82L/12; 82M/04; 82M/05; 92H/07; 92H/15; 92H/16; 92I; 92L; 92O/05; 92O/12; 92P; 93B/04; 93B/05; 93C/01; 93C/08; 93C/09; 93C/16; 93E/14; 93E/15; 93F; 93H/04; 93H/05; 93J/05; 93J/06; 93J/11; 93J/12; 93J/13; 93J/14; 93K; 93L/01; 93L/03; 93L/09; 93L/16; 93M/01; 93M/02; 93M/07; 93M/08; 93N; 93O/04; 94G; 94I/09; 94I/10; 94I/11; 94I/12; 94I/13; 94I/14; 94I/15; 94I/16; 104B/11
Lat/Long OENS-141.0000 -124.0000 64.2500 60.0000
Lat/Long OENS-128.0000 -116.0000 60.0000 49.0000
Sujetsexploration de dépôts glaciaires; écoulement glaciaire; directions des mouvements de la glace; profils de dispersion; dépôts glaciaires; tills; potentiel minier; topographie glaciaire; or; argent; plomb; zinc; cuivre; Calotte glaciaire de la Cordillère; Batholite d'Iron Mask ; Mine Faro ; Mine Gibraltar ; géologie des dépôts meubles/géomorphologie; géologie des dépôts meubles/géomorphologie; Quaternaire; Quaternaire
ProgrammeÉtude des gîtes porphyriques, Initiative géoscientifique ciblée (IGC-4)
Résumé(disponible en anglais seulement)
For more than 20 years, provincial, territorial and federal geological surveys have implemented surficial geology and glacial sediment (till) sampling surveys within the Canadian Cordillera with the main objectives of using drift prospecting methods to evaluate the mineral potential of regions covered by glacial sediments. The surveys were completed by processing the till samples for geochemical analyses and tracing the bedrock source of anomalies in the up-ice flow direction. Several mineral exploration targets have been identified by these surveys and followed-up by mineral exploration companies. The success of these surveys and subsequent follow-up relies on reconstructed ice-flow histories based on mapping of glacial sediments and ice-flow indicators varying from landform (e.g. drumlins) to outcrop (e.g. striae) scales.
During the last glacial maximum (LGM), the Canadian Cordillera was covered by the Cordilleran Ice Sheet (CIS) which was thick enough to flow across high summits in both the Rocky and Coast mountains. The position of ice source regions and ice-divides changed during the last glaciation such that ice-flow directions at LGM were different than in early and late glacial times. Northwest Yukon did not receive sufficient precipitation for extensive glacial ice build-up. The CIS left a clear foot print on the landscape including glacial landforms and thick successions of glacial sediments.
Recent developments and current research in the application of this drift prospecting methodology include: 1) the recognition of multiple ice-flow directions (including flow reversals) and associated glacial dispersal patterns, 2) the study of indicator minerals in sediments which could be traced to fertile mineralized bedrock sources, 3) recognition of mineral-rich dispersal trains in areas of thick till (> 30 m thick), and 4) the implementation of surficial sediment sampling strategies for the unglaciated landscape of northwest Yukon.