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Surficial geology and geomorphology of southern Hall Peninsula, Baffin Island, Nunavut: summary of the 2012 field season. Tommy Tremblay 1 , Michel Allard 2 , Paul Budkewitsch 3 , J. Gosse 4 , Anne-Marie Leblanc 5 , Patricia Peyton 6 , Julie Leblanc-Dumas 2 , and David Mate 1 (1) Canada-Nunavut Geoscience Office, Iqaluit, Nunavut (2) Centre d’étude Nordique, Université Laval, Québec, Québec (3) Aboriginal Affairs and Northern Development, Iqaluit, Nunavut (4) Department of Earth Sciences, Dalhousie University, Halifax, Nova Scotia (5) Geological Survey of Canada, Ottawa, Ontario (6) Environmental Technology Program, Nunavut Arctic College, Iqaluit, Nunavut [email protected]

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Surficial geology and geomorphology of southern Hall Peninsula, Baffin Island, Nunavut: summary of the 2012 field season.

Tommy Tremblay1, Michel Allard2, Paul Budkewitsch3, J. Gosse4, Anne-Marie Leblanc5, Patricia Peyton6, Julie Leblanc-Dumas2, and David Mate1

(1) Canada-Nunavut Geoscience Office, Iqaluit, Nunavut

(2) Centre d’étude Nordique, Université Laval, Québec, Québec

(3) Aboriginal Affairs and Northern Development, Iqaluit, Nunavut

(4) Department of Earth Sciences, Dalhousie University, Halifax, Nova Scotia

(5) Geological Survey of Canada, Ottawa, Ontario

(6) Environmental Technology Program, Nunavut Arctic College, Iqaluit, Nunavut

[email protected]

The Hall Peninsula Project

• The Hall Peninsula Integrated Geoscience Program (HPIGP) is being led by the Canada-Nunavut Geoscience Office in collaboration with the Government of Nunavut, Aboriginal Affairs and Northern Development Canada, Dalhousie University, University of Alberta, Université Laval, University of Manitoba, University of Ottawa, University of Saskatchewan, Nunavut Arctic College and the Geological Survey of Canada.

• It is supported logistically by several local, Inuit-owned businesses.

• The study area comprises all or parts of six 1:250 000 scale National Topographic System map areas north and east of Iqaluit (NTS 026A, B, 025I, J, O, P; Figure 1).

Overview

• Surficial geology is the study of the land, the way its been shaped by the action of glaciers, rivers, the sea, and the frost. Most of these events occured during the Quaternary period.

• The main tools used are soil sampling, airphotos, satellite images, and field observations.

• The principal uses for the maps are for roads, buildings, and mineral exploration.

• The maps are interesting for anyone looking for a scientific point of view on the land.

Focus of study

• Surficial geology maps at a scale of 1:100 000 on Hall

Peninsula.

• Ice flow regional study (striations measurements)

• Geochemistry and heavy fraction mineralogy of till

• Permafrost studies

• Inuktitut place-names project

Study area and location of till samples

Surficial geology maps

10 km

Simplified legend

Tor on felsenmeer surface (local cold-based ice in linear erosion dynamical setting) at the outer edge of Lemieux Island.

Geomorphology

Glacio-fluvial channel eroding the regolith cover down to solid bedrock. the presence of regoliths, felsenmeers and feebly eroded bedrock outcrops suggest that cold-based glaciers have covered the central part of the region during the Late Pleistocene.

Warm-based glacier valley and cold-based plateau in linear erosion dynamical setting, Blunts Peninsula. This bay is named Isingujjuaq on the traditionnal place-names map from Inuit Heritage Trust (2009), and hosted a cabin where whalers stayed a long time ago.

Geomorphology

RapidEye 5m resolution satellite image (red, blue and infrared as green); see dotted box close to McKeand River in location map. The main feature is the Frobisher Bay moraine (green on the image), displaying kettle lakes and ice-thrust moraine ridges.

Geomorphology

Juxtaglacial gravelly glaciofluvial deposit, Hall Peninsula plateau.

Glacial sediments , moraines and silt-laden glacial meltwater river, eastern Hall Peninsula.

Sandy deltas and moraines, ancient remains of glaciers from the past

Valley glacier, draining from the ice cap toward a glacial lake

Valley glacier, draining from the ice cap toward a frontal moraine

Marine sediments on the littoral of Frobisher Bay.

Geomorphology

Glacial striations uncovered on the bedrock surface, indicating Ice flow direction for the past glaciations

Ice flow history

Glacial dynamic setting CB, cold-based area; IB, intermediate-based area; IB/ L, mix of intermediate-based and linear selective glacial erosion areas; L, linear selective glacial erosion; WB, warm-based area.

Ice flow history

Permafrost studies

Iqaluit surficial geology maps for permafrost related studies (Leblanc et al., 2013; Allard et al., 2012)

Traditional place names project

Inuit Heritage Trust

Patricia Peyton

Economic considerations

-The scientific results stemming from the surficial geology studies of CNGO’s HPIGP will contribute to helping Canadians make better decisions concerning the management of their natural resources.

-The surficial maps and geomorphological studies (glaciodynamic mapping, permafrost, satellite images and uplift history) will help to minimize risk associated with mineral exploration in glaciated terrain and optimize the design of infrastructure projects.

-Till geochemical (ICP-MS, on less than 63um fraction) and mineralogical data (treated at ODM, Nepean, Ontario) will contribute to more efficient mineral exploration and assessment of environmental and geotechnical characteristics of soil.

Bedrock Geology (Machado et al., 2013)

Olivines in till (HM)

Till (HM)

Gold grains in till (HM)

Till (Geochemistry)

Till (Geochemistry)

Platinoid-bearing mineral grains in till (HM)

Till (Geochemistry)

Pyrite grains in till (HM)

Chalcopyrite grains in till (HM)

Till (Geochemistry)

Till (Geochemistry)

Summary

• Surficial geology maps is under way, at a scale of 1:100 000 on Hall Peninsula. • Ice flow regional study (striations measurements) maps are available:

Tremblay, T., Leblanc-Dumas, J., Allard, M., Gosse, J.C., Creason, C.G., Peyton, P., Budkewitsch, P. and LeBlanc, A-M.

2013: Surficial geology of southern Hall Peninsula, Baffin Island, Nunavut: summary of the 2012 field season. in Summary of Activities 2012, Canada- Nunavut Geoscience Office, p. 93-100.

• Geochemistry and heavy fraction mineralogy of till highlights includes sapphires (2 locations), KIMs (olivines, chrome-diopside), gold grains and sperrylite (platinoid).

• Permafrost studies will be helpful to future infrastructure project design.

• Inuktitut place-names project will link known with field pictures and geomorphological and geological description.

Aknowledgement

• Universal Helicopters pilots (J. Abbott, S. Sande, J. Hines, K. Cashin) provided safe field transport during the summers of 2011 and 2012. N. Maniapik and M. Qillaq provided valuable camp management, field assistance and bear monitoring. Preparation and interpretation of surficial mapping, glacial history and geomorphology was enhanced by discussions with R. Paulen (Geological Survey of Canada), M. Ross (University of Waterloo), C. Johnson (University of Waterloo), D. Mate (CNGO), M. Lamothe (Université du Québec à Montréal) and C. Knudsen (Geological Survey of Denmark and Greenland). Surficial mapping is prepared using three dimensional technology with the assistance of C.Gilbert (CNGO) and M.Boutin (Institut national de la recherche scientifique).