New geologic mapping + and associated economic potential on northern Hall Peninsula, Baffin Island, Nunavut

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1 New geologic mapping + and associated economic potential on northern Hall Peninsula, Baffin Island, Nunavut Holly Steenkamp, M.Sc. Regional Mapping Geoscientist David Mate, M.Sc. Chief Geologist November 21, 2013

2 Hall Peninsula Integrated Geoscience Project Gather geoscience information to aid in accurately interpreting the tectonostratigraphic and metamorphic evolution of Hall Peninsula, and evaluate the potential for economic resources in this area. Collaborative effort 7 Canadian universities (2 PhD, 5 MSc, 1 BSc) GSC - Ottawa AANDC GN Nunavut Arctic College Field mapping in 2012 and 2013 Bedrock at 1:250,000 Surficial sediment at 1:100,000 Detailed thematic studies

3 Hall Peninsula Integrated Geoscience Project 2013 Field Campaign Northern Hall Peninsula 10 days out of Iqaluit 38 days out of Sunrise Camp (rented from Peregrine Diamonds) Traverses and targeted helicopter stops ᐱᓕᕆᕝᕕᐅᔪᑦ Project Areas:

4 Bedrock Field Observations Eastern Rock Units: Archean basement orthogneiss - tonalite to monzogranite Steenkamp and St-Onge (in press)

5 Bedrock Field Observations Eastern Rock Units: Archean basement orthogneiss - tonalite to monzogranite Overlain by supracrustal strata - quartzite, psammite, pelite, ironstone, amphibolite, calcsilicate units - record amphibolite-facies metamorphism Steenkamp and St-Onge (in press)

6 Bedrock Field Observations Western Rock Units: Supracrustal strata - psammite to pelite - record granulite-facies metamorphism Steenkamp and St-Onge (in press)

7 Bedrock Field Observations Western Rock Units: Supracrustal strata - psammite to pelite - record granulite-facies metamorphism Opx±Cpx±Mag felsic intrusives - tonalite to quartz diorite - charnockite panels Steenkamp and St-Onge (in press)

8 Bedrock Field Observations Western Rock Units: Supracrustal strata - psammite to pelite - record granulite-facies metamorphism Opx±Cpx±Mag felsic intrusives - tonalite to quartz diorite - charnockite panels Grt±bt leucogranite - Likely generated by muscovite and/or biotite dehydration melting in supracrustal units Steenkamp and St-Onge (in press)

9 Bedrock Field Observations Metamorphism: Increasing grade from E to W Deformation: 3 major phases documented Steenkamp and St-Onge (in press)

10 Bedrock Field Observations Metamorphism: Increasing grade from E to W Deformation: 3 major phases documented D 1 D 2 Steenkamp and St-Onge (in press)

11 Bedrock Field Observations Metamorphism: Increasing grade from E to W Deformation: 3 major phases documented D 3 Steenkamp and St-Onge (in press)

12 Bedrock Field Interpretations 1. Paleoproterozoic sedimentary strata suggest gradational change from shallow marine to shelf or slope-rise depositional setting within proximity to a local rifting environment. 2. Increasing metamorphic grade from E to W, and fold and thrust geometry likely represent a transition from an orogenic foreland to hinterland, related to the terminal collision of the Trans-Hudson Orogen. Steenkamp and St-Onge (in press)

13 Economically Interesting Finds Two layered maficultramafic intrusions 25 ultramafic intrusions with post-emplacement hydrothermal alteration 9 silicified gossans Calc-silicate containing marble and semi-precious fluorapatite Granitic pegmatites Steenkamp and St-Onge (in press); Steenkamp et al. (in press)

14 Layered Mafic-Ultramafic Intrusions Ni-Cu-PGE Northern LM-UI Southwestern LM-UI Steenkamp et al. (in press)

15 Northern LM-UI Three segments over ~7 km distance Sills emplaced in garnet-biotitepsammite Rip-up clasts embedded in base of intrusion Magmatic internal layering from clinopyroxenite to layered peridotite to gabbro Tectonic context and mineralogy comparable to the upper Raglan-type deposits in the Cape Smith Belt in northern Quebec Steenkamp et al. (in press)

16 Northern LM-UI Three segments over ~7 km distance Sills emplaced in garnet-biotitepsammite Rip-up clasts embedded in base of intrusion Magmatic internal layering from clinopyroxenite to layered peridotite to gabbro Tectonic context and mineralogy comparable to the upper Raglan-type deposits in the Cape Smith Belt in northern Quebec

17 Northern LM-UI Three segments over ~7 km distance Sills emplaced in garnet-biotitepsammite Rip-up clasts embedded in base of intrusion Magmatic internal layering from clinopyroxenite to layered peridotite to gabbro Tectonic context and mineralogy comparable to the upper Raglan-type deposits in the Cape Smith Belt in northern Quebec

18 Hydrothermally Altered Ultramafics Carving Stone Basement-hosted Isolated plugs or boudinaged sills Alteration pervasive at contact Supracrustal-hosted Laterally continuous sills Penetrative alteration throughout Primary ultramafic mineralogy replaced by tremolite, actinolite, phlogopite, serpentine, and minor talc Potential source of carving stone Basement-hosted Supracrustal-hosted

19 Silicified Gossans Sulphide Mineralization Hosted in supracrustal strata Locally associated with graphite schist Pyrrhotite- and pyritebearing

20 Calc-silicate Marble Carving Stone & Fluorapatite Typically found near the base of the supracrustal stratigraphy Contains minor layers and lenses of marble Possible source of carving stone Blue fluorapatite documented at one locality Possible source of semiprecious gemstone

21 Granitic Pegmatites Rare Earth Elements Relatively late, cross-cut through basement and supracrustal strata Concentrated in the eastern portion of field area Contain biotite, muscovite, and/or tourmaline Potential source of Rare Earth elements.

22 Continued Research & Future Work University collaborators continue to collect analytical data: Geochronology: deposition, intrusion, and metamorphism Geochemistry of mafic and ultramafic units Isotope geochemistry to characterize the basement orthogneiss components Pressure and temperature estimates of metamorphism Regional uplift CNGO 2013 Summary of Activities (January 2014) Articles and raw datasets will be available for download from /2015: Final Hall Peninsula field season - targeted mapping and thematic studies Rare Earth element potential of granitic pegmatites Northern Hall Peninsula geological map (April 2014) Hall Peninsula surficial geology map (2014) Hall Peninsula geological compilation map (Early 2015)

23 Thank you! Hall Peninsula Geoscience Crew Peregrine Diamonds Ltd. De Beers Canada Exploration Universal Helicopters University of Alberta Dalhousie University Université Laval University of Manitoba University of Ottawa University of Saskatchewan University of Waterloo