| Title | The Strange Lake dispersal train: a product of a hard-bedded ice stream |
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| Author | Paulen, R C ;
Stokes, C R; Fortin, R; McClenaghan, M B; Rice, J M; Dubé-Loubert, H |
| Source | GAC-MAC 2017, abstracts/GAC-MAC 2017, résumés; Geological Association of Canada-Mineralogical Association of Canada, Joint Annual Meeting, Abstracts Volume vol. 40, 2017 p. 303  Open Access |
| Links | Online - En ligne (complete volume, PDF, 3.09
MB)
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| Image |  |
| Year | 2017 |
| Alt Series | Earth Sciences Sector, Contribution Series 20160432 |
| Publisher | Geological Association of Canada |
| Meeting | Geological Association of Canada - Mineralogical Association of Canada, Joint Annual Meeting; Kingston, ON; CA; May 14-18, 2017 |
| Document | serial |
| Lang. | English |
| Media | on-line; digital |
| File format | pdf |
| Program | GEM2: Geo-mapping for Energy and Minerals Hudson/Ungava, Northeastern Quebec-Labrador, surficial geology |
| Released | 2017 05 01 |
| Abstract | The Strange Lake glacial dispersal train, in northern Quebec and Labrador, is a remarkably linear, ribbon-like geochemical dispersal pattern trending >40 km down ice (northeast) from a mineralized rare
earth element (REE) peralkaline intrusion. Recent mapping of Laurentide Ice Sheet streams by Margold and others in 2015, places the Strange Lake train directly within the trunk of the Kogaluk River ice stream (IS #187), one of a number of ice streams
that operated near the center of the Labrador dome and drained into the Atlantic Ocean. In soft-bedded areas, subglacial landforms can be used to map the spatial extent of ice stream tracks (e.g., megascale glacial lineations, ice stream shear margin
moraines). Over hard-bedded, higher relief areas, the geomorphic imprint of ice streams tends to be less obvious, and sometimes features, such as shear margin moraines, can be completely absent. Despite the relatively thin till cover in the Strange
Lake area, fast-flowing ice formed spectacular crag-and-tail landforms down ice of bedrock outcrops (up to 5 km long, with length:width ratios exceeding 12 and higher) within the dispersal train.
Airborne gamma-ray spectrometry surveys conducted
in the Lac Brisson region in the 1980s show a subdued signal over part of the Strange Lake deposit and a long equivalent thorium (eTh) ribbon that extends more than 60 km to the northeast, well beyond the till geochemistry train. Deposition of
REE-sediment was also controlled, in part, by the local rugged bedrock topography. Sediment dispersal trains, coupled with erosive corridors of streamlined terrain, provide a potentially powerful means of identifying 'hard-bedded' ice streams
elsewhere in northern Canada. |
| Summary | (Plain Language Summary, not published)
A poster presentation to academic peers, to present and discuss field observations and results from a re-interpretation of the Strange Lake dispersal
train, in modern glacial science context, in particular, it being impacted by a former ice stream. |
| GEOSCAN ID | 299872 |
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