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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

Hall Peninsula Integrated Geoscience Project

• 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

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.

ᐱᓕᕆᕝᕕᐅᔪᑦ Project Areas:

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

Bedrock Field Observations

Eastern Rock Units:

• Archean basement orthogneiss
• tonalite to monzogranite

Steenkamp and St-Onge (in press)

Bedrock Field Observations

Eastern Rock Units:

• Archean basement orthogneiss
• tonalite to monzogranite
• Overlain by supracrustal strata
• quartzite, psammite, pelite,

ironstone, amphibolite, calc- silicate units

• record amphibolite-facies

metamorphism

Steenkamp and St-Onge (in press)

Bedrock Field Observations

Western Rock Units:

• Supracrustal strata
• psammite to pelite
• record granulite-facies

metamorphism

Steenkamp and St-Onge (in press)

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)

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)

Bedrock Field Observations

Metamorphism:

• Increasing grade from E to W

Deformation:

• 3 major phases documented

Steenkamp and St-Onge (in press)

Bedrock Field Observations

Metamorphism:

• Increasing grade from E to W

Deformation:

• 3 major phases documented

D1 D2

Steenkamp and St-Onge (in press)

Bedrock Field Observations

Metamorphism:

• Increasing grade from E to W

Deformation:

• 3 major phases documented

D3

Steenkamp and St-Onge (in press)

• 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.

Bedrock Field Interpretations

Steenkamp and St-Onge (in press)

Economically Interesting Finds

• Two layered mafic-

ultramafic 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)

Layered Mafic-Ultramafic Intrusions – Ni-Cu-PGE

Northern LM-UI Southwestern LM-UI

Steenkamp et al. (in press)

Northern LM-UI

• Three segments over ~7 km distance
• Sills emplaced in garnet-biotite-

psammite

• 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)

Northern LM-UI

• Three segments over ~7 km distance
• Sills emplaced in garnet-biotite-

psammite

• 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

Northern LM-UI

• Three segments over ~7 km distance
• Sills emplaced in garnet-biotite-

psammite

• 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

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

Silicified Gossans – Sulphide Mineralization

• Hosted in supracrustal

strata

• Locally associated with

graphite schist

• Pyrrhotite- and pyrite-

bearing

Calc-silicate – Marble Carving Stone & Fluorapatite

• Typically found near the base
• f the supracrustal

stratigraphy

• Contains minor layers and

lenses of marble

• Possible source of carving

stone

• Blue fluorapatite documented

at one locality

• Possible source of semi-

precious gemstone

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.

• 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 www.cngo.ca

• 2014/2015:

– 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)

Continued Research & Future Work

Hall Peninsula Geoscience Crew Peregrine Diamonds Ltd. De Beers Canada Exploration Universal Helicopters

Thank you!

University of Alberta Dalhousie University Université Laval University of Manitoba University of Ottawa University of Saskatchewan University of Waterloo