| Title | The Cabot Lake ice-stream: a hard-bedded palaeo-ice-stream near the Ancestral Labrador Ice-Divide of the Laurentide Ice Sheet's Quebec-Labrador Dome |
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| Author | Rice, J ; Ross,
M; Paulen, R |
| Source | INQUA 2019 - 20th Congress of the International Union for Quaternary Research (INQUA), programme; 2019 p. 1  Open Access |
| Links | Online - En ligne
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| Image |  |
| Year | 2019 |
| Alt Series | Natural Resources Canada, Contribution Series 20180368 |
| Publisher | International Union for Quaternary Research |
| Meeting | INQUA 2019 - 20th Congress of the International Union for Quaternary Research (INQUA); Dublin; IE; July 25-31, 2019 |
| Document | Web site |
| Lang. | English |
| Media | on-line; digital |
| Related | This publication is related to The Cabot Lake Ice Stream: a
paleo-ice stream near the Ancestral Labrador Ice Divide of the Laurentide Ice Sheet's Quebec-Labrador dome |
| File format | html; pdf (Adobe® Reader®) |
| Province | Newfoundland and Labrador; Quebec |
| NTS | 13L/11; 13L/12; 13L/13; 13L/14; 13M/03; 13M/04; 13M/05; 13M/06; 23I/09; 23I/10; 23I/15; 23I/16; 23P/02; 23P/07; 23P/08 |
| Area | Labrador; Cabot Lake; Lac aux Goélands; Signal Hill |
| Lat/Long WENS | -65.0000 -63.0000 55.5000 54.5000 |
| Subjects | surficial geology/geomorphology; Nature and Environment; Science and Technology; glacial history; glaciation; deglaciation; ice flow; glacial deposits; glacial landforms; glacial features; glacial
striations; lineations; sediment transport; sediment dispersal; Laurentide Ice Sheet; Cabot Lake Ice Stream; Ancestral Labrador Ice Divide; Quebec-Labrador Dome; Canadian Shield; Kogaluk River Ice Stream; Smallwood Ice Stream; De Pas Batholith; Happy
Valley-Goose Bay Ice Stream; ice streams; ice-flow directions; Phanerozoic; Cenozoic; Quaternary |
| Program | GEM2: Geo-mapping for Energy and Minerals Hudson/Ungava, Northeastern Quebec-Labrador, surficial geology |
| Released | 2019 07 01 |
| Abstract | The Cabot Lake ice-stream (CLIS) is a previously unidentified east-trending ice-stream on the Canadian Shield that provides evidence for rapid basal-flow acceleration in close proximity to an
ice-divide. The CLIS is located near the central-eastern border of Quebec and Newfoundland and Labrador, between two much larger ice-stream corridors. The CLIS is situated south of the Kogaluk River Ice-Stream near Strange Lake (IS #185 of Margold et
al. 2015), and north of the unnamed ice-stream in the Smallwood Reservoir (herein referred to as the Smallwood ice-stream). The CLIS occupies a lowland region in the headwaters of the George River and is bounded on its onset zone and terminus by
large bedrock upland regions: the Paleoproterozoic De Pas Batholith at its onset in the west and the Neoarchean granite and orthogneiss at its terminus in the east. The CLIS is 40 km wide at its onset, with a classic converging flow pattern and sharp
lateral margins that narrows to 20 km wide near its terminus, where it abruptly ends at an intrusive bedrock upland region. The CLIS contains over 1000 streamlined landforms, many with elongation ratios of 12:1 or greater. The CLIS was relatively
short-lived, given its extent, and following the ice streaming, the system shutdown with sluggish, topographically-controlled ice-flow to the northeast, which explains the high degree of preservation of the landforms and lack of a time-transgressive
land system that would result from gradual glaciological changes. This younger northeastern ice-flow was oblique to the eastern-trending CLIS bedforms, as indicated by striations on nearby bedrock highlands and moderate reworking of some of the
MSGLs.
This ice-stream operated near a migrating dispersal saddle of the Laurentide Ice Sheet's Quebec-Labrador dome in central-eastern Quebec. The CLIS' proximity to this ice-divide suggests that ice-streams were active toward the centre of the
ice-sheet during late-stage deglaciation. The timing and duration of the ice-stream remain undefined; however, it shares a similar longitude to the Happy Valley-Goose Bay ice-stream to the south (IS #186 of Margold et al. 2015), another short
ice-stream that is thought to have been active at about 8.9 cal ka BP. The location of the CLIS in such close proximity to an ice-divide, in conjunction with the other ice-streams operating simultaneously along the eastern margin of the retreating
Laurentide Ice Sheet (e.g., Kogaluk River, Smallwood, and Happy Valley-Goose Bay ice-streams) indicate these ice-streams had an important impact on the transportation of glacial sediments away from core-regions of the ice dispersal-centre and
possibly influenced the westward migration of the ice-divide during deglaciation. |
| Summary | (Plain Language Summary, not published)
This is GEM-2 funded student PhD research being presented at an international conference, in a special session on ice streams. |
| GEOSCAN ID | 313539 |
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