QUATERNARY GEOLOGY STUDIES IN CENTRAL MELVILLE PENINSULA, NUNAVUT Tremblay, T.1, Paulen, R.2 and Corrigan, D.2 (1) Canada-Nunavut Geoscience Office, Iqaluit, NU (2) Geological Survey of Canada, Ottawa, ON [email protected] Carbonated till over Precambrian rocks Partners Igloolik, NU This project is funded by the Geo-Mapping for Energy & Minerals (GEM) program (2008-2013) and from the Canada- Nunavut Geoscience Office. Geological Survey of Canada-Ottawa Geological Survey of Canada-Québec Universities (Université du Québec à Montréal, Dalhousie) Hall Beach, Repulse Bay and Igloolik communities Plan 1. Ice flow studies (summer 2009 field work) 2. Economic potential from till geochemistry (from Dredge, 1995, 2002, 2004 and 2009) 3. Lake sediments geochemistry (Day et al., 2009) 4. Future work and sample analysis Highlights • Glacial geology indicates different till types (cold- based, warm-based, shield, carbonated) which impact on glacial dispersal trains aspect • An ice flow reversal is documented in the eastern part of the Peninsula • From geochemistry in till and lake sediment -Prince Albert Gr. (PAG) show potential for Ni, Cu, Cr, V, Pb, Ag, Au, Mo -Penrhyn Gr. Show potential for Au, U, Pb, Zn, Mo Study area and bedrock geology Landsat image DEM and till types Warm-based Warm-based Cold-based Cold-based ice: extensive weathering of outcrops Warm-based ice: ice moulded bedrock forms, with faint post-glacial weathering Glacial geomorphology (Dredge, 1995, 2002) Glacial striae Striae synthesis Ice flow history Ice flow history Ice flow history Late glacial ice divide Ice flow reversal 2. (SE) 1. (NW) Petrographic countings on till pebbles Petrographic counting on till pebbles Petrographic counting on till pebbles 2. Economic potential from till geochemistry (from Dredge, 1995, 2002, 2004 and 2009) Bedrock geology and till types Gossan localization (Dredge, 1995, 2002) Ice flow on Melville Peninsula (Dredge, 2002) Till geochemistry Ni Till geochemistry Ni Ice flow for Melville north Till geochemistry Cr Till geochemistry Co Till geochemistry Fe Till geochemistry V Till geochemistry Cu Till geochemistry Pb Till geochemistry Zn Till geochemistry Au Till geochemistry As Till geochemistry Bi Till geochemistry Sb Till geochemistry Ag Till geochemistry Mo Till geochemistry U 3. Lake sediment geochemistry Lake sediments Mafic deposits elements (Day et al. , 2009) Lake sediments Mafic deposits elements (Day et al. , 2009) Till Lake sediments Mafic deposits elements (Day et al. , 2009) Till Lake sediments Base metals deposits elements (Day et al. , 2009) Lake sediments Base metals deposits elements (Day et al. , 2009) Till Lake sediments Base metals deposits elements (Day et al. , 2009) Till Gold pathfinder elements (Day et al. , 2009) Gold pathfinder elements (Day et al. , 2009) Lake sediments Gold pathfinder elements (Day et al. , 2009) Till As (2 um, ppm) Till As (63 um, ppm) Lake Sediment Au (Day et al. , 2009) Lake Sediment U (Day et al. , 2009) Summer 2009 till sampling (red dots), and Ni (orange bubbles) Ni, Till (63 um) Conclusions North-central Melville Peninsula • 3 phases ice flow history: 1. NW – W (LGM?), 2. W, converging to Garry Bay (deglacial), 3. SE, ice flow reversal to Foxe Basin (deglacial) • Cold-based zone divided into total and intermediate zones, associated with reduction of ice flow transport distances, especially in total cold-based zone • Glacial transport of erratics (PAG, carbonates) indicates preponderance of Phase 1 and 2 on the main plateau, and the lesser importance of Phase 3 Conclusions (suite) Principal anomalous zones, from till and lake sediments geochemistry • W PAG – Cu, Pb, As(Au?), Ag, Mo • E PAG – Ni, Cu, Cr, V, Au?, Fe • Penrhyn Gr. – U, Au, Pb, Zn, Mo From published HM in till data: Tremblay Lake area (kimberlites) Future work • Summer 2009 till samples: -HM geochemical analysis for base metals (Ni, Cu, Cr, Pb, Ag, Mo, PGE), focus on PAG -Gold grains counts in HM, focus on PAG -HM analysis for KIM, regional scale • Summer 2010 field season: -Till sampling for HM analysis, focusing on Penrhyn Gr. most prospective areas (Au, U, Pb, Zn). -Detailled ice flow history for Melville south Aknowledgements Linda Dredge (GSC-Ottawa, till geochemistry) Steve Day (GSC-Ottawa, lake sediments geochemistry) Melville Bedrock mapping crew, co-leaded by David Corrigan (GSC-Ottawa) and Léopold Nadeau (GSC-Quebec) Assistants: Benoît Soucy-De Jocas, Scott Robinson, Lindsay Richan. Universal Helicopter Newfoundland and Labrador Pierre Brouillette, Marco Boutin, Annick Morin, Celine Gilbert and Julien Paradis provided technical support with digital field data acquisition, GIS and IT. Linda Ham and Steve Sharpe (INAC) Assistants from Hall Beach community .