Preliminary report on ice-flow history, deglacial chronology, and surficial geology, Foxe Peninsula, southwest Baffin Island

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1 Earth Sciences Sector Northern Resources Development Preliminary report on ice-flow history, deglacial chronology, and surficial geology, Foxe Peninsula, southwest Baffin Island Daniel Utting

Southwest Baffin Integrated Geoscience Project The primary objective of SWBIG is to

Island region by improving the level of geoscience information.

analyses (talks today) Aeromagnetic (geophysical) surveys Remote Predictive Mapping

3 Southwest Baffin Integrated Geoscience Project The primary objective of SWBIG is to enhance mineral exploration and development opportunities in the southwest Baffin Island region by improving the level of geoscience information. Project includes: Bedrock and surficial geology mapping (talks today) Geochemical analyses (talks today) Aeromagnetic (geophysical) surveys Remote Predictive Mapping Ethnogeography studies Community visits to improve the chances for successful mineral discoveries in the region.

4 First-ever regional magnetic survey of southwest Baffin, funded by the Qikiqtani Inuit Association (available for free download: Mark Pilkington (GSC-Ottawa)

5 Remote Predictive Mapping Work hyperspectral data, integrated Earth observation maps, and Baffin Landsat Mosaic Iqaluit Cape Dorset Kimmirut

6 Integrated Earth Observation Map Integrated Earth Observation Map 36H (South Half)

8 Surficial Geology Component

9 Hulbe et al. 2004

12 Ice-flow phase 1, inferred at Last Glacial Maximum (LGM) until ca. 10 ka 14 C ka BP (11.35 cal ka BP) Hudson Strait: Ice flowed towards the east. East: flow was predominantly to the southwest, flowing from the Amadjuak Ice Divide. West: flow towards the southeast possibly from the Foxe Divide. This flow may have been responsible for transporting pre-last glacial shell fragments onto the peninsula, above marine limit. Main flow was influenced by Foxe Dome and was to the south. Inset maps modified from Dyke (2004), margin(s) also appear as dotted lines on main maps. Ice divides are labeled with F for Foxe Divide, A

13 Ice-flow phase 2, inferred at 8 14 C ka BP (8.98 cal ka BP). Flow in the western sector shifted southwards and slightly southwest, as an apparently greater control was exerted from the Amadjuak Divide. Flow in the eastern sector still to southwest. Inset maps modified from Dyke (2004), margin(s) also appear as dotted lines on main maps. Ice divides are labeled with F for Foxe Divide, A

Ice-flow phase 3, inferred at 7 14 C ka BP (7.8 cal ka BP), (ice divides shown are from 8 14 C ka BP (Dyke and Prest 1987) with an additional divide on Foxe Peninsula).

14 Ice-flow phase 3, inferred at 7 14 C ka BP (7.8 cal ka BP), (ice divides shown are from 8 14 C ka BP (Dyke and Prest 1987) with an additional divide on Foxe Peninsula). Retreating ice on the eastern south-coast is deflected down the troughs and rias. As deglaciation progressed, an ice divide may have run generally north-south dissecting the peninsula, as recorded by the oldest flow at crosscutting site A. De Geer moraines in central lowlands suggests a grounded ice margin, that retreated northwards. Inset maps modified from Dyke (2004), margin(s) also appear as dotted lines on main maps. Ice divides are labeled with F for Foxe Divide, A

15 Ice-flow phase 4, inferred at C ka BP (7.45 cal ka BP). Streamlined landforms suggest fast ice flow, which may have resulted from flow towards a rapidly retreating ice margin/ice shelf in Foxe Basin from the Amadjuak Dome. Inset maps modified from Dyke (2004), margin(s) also appear as dotted lines on main maps. Ice divides are labeled with F for Foxe Divide, A

16 Ice-flow phase 5, inferred at C ka BP (6.3 cal ka BP). Late stages of retreating ice in northeast area, flow direction parallel to eskers. Inset maps modified from Dyke (2004), margin(s) also appear as dotted lines on main maps. Ice divides are labeled with F for Foxe Divide, A

Western sector shows depleted shield values and

18 shield material Paleozoic material Streamlined features in NE show elevated shield values Western sector shows depleted shield values and elevated Ca, suggesting transport of till from Foxe Basin.

19 Hulbe et al. 2004

23 Acknowledgements Don James and Dave Scott: project masterminds. Surficial field crew: J. Gosse, D. Hodgson, S. Kelley, M. Trommelen, K. Vickers, B. Ward Exceptional expediting services were provided by K. Brazel, O. Brown, and A. Faubert at the CNGO, and F. Schnell in Cape Dorset. Thanks to O. Brown, G. Buller and K. Shimamura for developing the surficial version of the Ganfeld ArcPad data collection. Thanks to W. Blake for providing preliminary maps based on his work in 1965 and to K. Brazel for digitizing these. And we would like to thank the rest of the field crew.

QUATERNARY GEOLOGY STUDIES IN CENTRAL MELVILLE PENINSULA, NUNAVUT

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,