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SurficialSurficial Geology,Geology, QuaternaryQuaternary HistoHistoryry andand Prospecting,Prospecting, NorthNorth BaffinBaffin ProjProjectect Utting, D.1, Little, E.2, Young, M.1, McCurdy, M.2, Coulthard, R.3, Gosse, J.4, Staiger, J.4 and Brown, O.1 1Canada-Nunavut Geoscience Office; 2Geological Survey of Canada; 3University of Alberta, 4Dalhousie University Introduction Introduction GGllaacciiaall HHiissttoorryy In 2005, the Canada Nunavut Geoscience Office, in collaboration with the Geological Survey of Canada, the University of Alberta, Dalhousie University, and the Polar Continental Shelf Project, expanded the 2003 North Baffin Project from Ice Bound Lakes (NTS 37G), to Conn Lake (NTS 37E) and south Buchan Gulf (NTS 37H/South)(Figure 1). The area lies along the northeast coast of Baffin Island between Bylot Island and the Clyde foreland; areas with contrasting ice sheet Cockburn Moraine reconstructions and chronologies. Hence, the study area provides a unique opportunity to resolve controversial issues, and will have broader implications for regional drift prospecting programs. The primary goal of this study is to reduce the mineral exploration risk in this remote area by improving the existing geoscience knowledge base. The project involves mapping the surficial geology at 1:100 000 scale, as well as collection of drift, stream and bedrock prospecting samples, and detailed bedrock mapping of key localities. To date, 321 samples have been collected for till geochemistry and KIM analyses, 31 DeGeer Moraine stream sediment samples were collected for geochemistry and KIM Figure 3.1 Figure 3.2 analyses, 123 bedrock samples have been collected for assay, and 90 for lithogeochemical analyses. In addition, the project has yielded 1387 ground-truthing sites, 314 paleo-ice movement measurements, and Ice Flow Indicators ►314 paleo-ice movement indicators have been collected in the study area. the collection of 27 cosmogenic samples and 41 radiocarbon samples ►Fewer than expected measurements were collected in the area northeast of the Barnes Ice Cap, for geochronology and research into glacial dynamics influencing speculatively because much of this study area was covered by cold based ice. North Baffin's surficial geology. ►Sedimentary erratics, thought to be of Paleozoic age (i.e. from Foxe Basin), were most commonly found in the northwest of 37E, and the west of 37H/south. There are more of these erratics in 37G. The complex glacial history resulted from overprinting of both erosive Neoglacial Moraine and non-erosive basal thermal regimes at various stages of the Glacial History deglaciation (a likely characteristic along much of the eastern margin Based on previous work, and preliminary results of ice movement indicators, erratic dispersal patterns and geomorphological observations, a tentative glacial of Canada) as well as overprinting of LGM-related geomorphology with history can be constructed for the study area. In full glacial times (Phase 1, Figure 3.1): those of the paleo- and modern-day Barnes Ice Cap. To resolve this, 1. Ice likely reached the outer coast by flowing through the deep trough of Buchan Gulf and flowed out to at or near the shelf margin. Slightly less new applications were developed that compare the terrestrial extensive ice was also diverted through the North Arm and Coutts Inlet (Hodgson and Haselton, 1974). In the west (37G), ice was directed to the north cosmogenic nuclide concentrations in glaciolacustrine deltaic out of Tay Sound and Paquet Bay towards the Navy Board Inlet Ice Stream (Dyke and Hooper, 2001), and probably out of Pond Inlet (not the town) (Dyke, sediment, till, and large (~2x2x2 m) boulders to quantify variations in 2004, cf. Klassen, 1993). the plateau-wide erosion rate and to qualitatively assess the duration 2. The uplands on some parts of the outer coast were likely beyond or above the extent of the ice sheet, or coalesced only for a short period. These areas of glacial transport and ice velocity. were glaciated by actively eroding, local, alpine-style glaciers. 3. Farther inland, the uplands were likely glaciated by less erosive ice caps that may or may not have coalesced with the ice sheet. Es In ki 4. The area northeast of the Barnes was likely covered with less erosive cold based ice, based on the limited number of small lakes and relatively few ice le mo Nova Zembla t Island Milne movement indicators. Oliver m Inlet r h A ug Tay Paquet Glacier h ro t t T r n 5. The area to the southwest of the Barnes was covered with more active eroding ice that may have flowed as an ice stream across Baffin Island into the Sound o e a Bay l h N n uc I lf B Milne Inlet drainage Gu s t n t ha Icebound u uc Rannoch arm area, and deposited the sedimentary erratics. o B Lakes C Icy Arm d d T Quernbiter r r u o o rne Fiord i i F F r R y The retreat phase can be characterized by: i t v Rannoch e e i r Arm c Omega e er o v g i Bay S ►Ice retreating up the fiords, and, where applicable, becoming disconnected with upland ice. Ice had retreated to a mid-fiord position in both d d R i l r r d n Aird Point b a io r v y o m F i a o Angajurjualuk a F Scott R R o C y Cambridge and Royal Society Fiord by about the time of formation of the Cockburn moraines (Phase 2, Figure 3.2). Based on Dyke's (2004) regional Lake s er t Inlet i iv r l R m ee e K o t Buchan Gulf r x lar T C k e Fior reconstructions of glaciation, ice was still grounded in Foxe Basin at 8 000 years (i.e. during formation of the Cockburn moraines), and was not related Ravn D d drainage Lethbridge drainage Lakes Bruce Mountains R. d to paleo-Barnes flow as reported in Little et al. (2004), their phase 2. Erickson rn or u i Lake b s F k ibb oc G ►Later readvance (Phase 3, not shown) formed the Isortoq Phase moraines of Andrews (1966). C Rimrock Cockburn Lake Lake Isortoq drainage ►Continued deglaciation (Phase 4, not shown) resulted in the damming of several lakes in the study area and formation of DeGeer or cross-valley . Conn R m Lake r y A e n r moraines. h e s k Steensby l e d r Bieler a Inlet F o r Lake W ir e F Isor iv toq R d r o K F Isortoq in g Riv m Lake er Barnes a Ice Cap S DDoowwnnllooaaddss Isortoq Fiord PPrroossppeeccttiinngg Little, E.C., Dyke, A.S., Young, M. and Figure 1: Study area location, drainage basins and features Utting, D.J. 2005. Preliminary drift prospecting and bedrock geochemical discussed in this poster. results from the north Baffin project (NTS 37F, 37G, 47E) northern Baffin Island, Nunavut. Geological Survey of Canada Open File 4944, 239 p. TerrestrialTerrestrial CosmogenicCosmogenic NuclideNuclide Utting, D.J., Little, E.C., Brown, O., Young, M., and Taylor, J. 2005. Glacial geology, drift and bedrock prospecting, and ApplicationsApplications (TCN)(TCN) related remote sensing applications in Stream Sediment Sampling northern Baffin Island, Nunavut. (Poster) Till Sampling Geological Survey of Canada, Open File 4736, 2005; 1 sheet. Young, M.D., Sandeman, H., Berniolles, F., Gertzbein, P.M. 2004. A preliminary stratigraphic and structural geology framework for the Archean Mary River Group, northern Baffin Island, Nunavut. 2 Geological Survey of Canada, Current Research No. 2004-C1; 14 p. Little, E.C., Holme, P.J., Hilchey, A.C., 1 Young, M. 2004. Glacial geology, ice- movement chronology, and drift prospecting in the vicinity of Icebound Lakes, northern Baffin Island, Nunavut. 3 Geological Survey of Canada, Current Research No. 2004-B1; 16 p. Figure 2.1 Figure 2.2 Available from: Figure 4.1 Figure 4.2 http://geopub.nrcan.gc.ca/publist_e.php Figure 2.1: Map of 37G area showing surface till sites predicted to be deposited by either cold-based (blue or warm-based (red) ice (Staiger et Figure 4.1: To date, 321 samples have been collected for till geochemistry and KIM analyses, 156 of those were collect in 2005. al. 2005). 10Be concentrations in 104 atom·g-1. Four samples termed Figure 4.2: A total of 31 stream sediment samples were collected for geochemistry and KIM analyses. intermediate were classified as cold based tills, but have low 10Be 123 bedrock samples have been collected for assay, and 90 for lithogeochemical analyses (not shown). Little et al. (2005) RReeffeerreenncceess present data from the 2003 field season (see “Downloads”). Data from the 2005 field area will be released in a subsequent Andrews, J. T. 1966. Pattern of coastal uplift and concentrations. This technique deglacierization west Baffin Island, N.W.T.; report. Geographical Bulletin, v. 8, p. 174-193. allows for quantification of glacial Dyke, A. S. and Hooper, J. M. G. 2001. Deglaciation of northwest Baffin Island, Nunavut; scale 1:500 000; erosion and can be used to infer Geological Survey of Canada Map 1999A. Dyke, A. S. 2004. An outline of North American glacial transport distances. deglaciation with emphasis on central and northern OOtthheerr SSttuuddiieess Canada; in Quaternary glaciations - extent and Figure 2.2: TCN boulders samples chronology, part II. North America, (ed) P. L. ►Detailed bedrock mapping at key localities to refine structure and stratigraphy. Gibbard and J. Ehlers; p. 373-424. on 1) a deglacial transect roughly Hodgson, D. A. and Haselton, G. M. 1974. ►Glacial marine studies to improve deglacial chronology, in collaboration with the University of Alberta. Reconnaissance glacial geology, northeastern Baffin perpendicular to the current Island; in Paper 74-20; Geological Survey of Canada, ►Remote Predictive Mapping to produce predictive surficial geology maps from Landsat and Radarsat imagery.

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