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2. Laurentide Ice Sheet configuration in southern Ontario, Canada during the last glaciation (MIS 4 to 2) from stratigraphic drilling and LIDAR-based surficial mapping.
- Author
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Bukhari, Syed, Eyles, Nick, Mulligan, Riley, Burt, Abigail, Eyles, Carolyn, Paulen, Roger, Ross, Martin, and Putkinen, Niko
- Subjects
ICE ,LAST Glacial Maximum ,ICE sheets ,BEDROCK ,ICE streams ,GLACIAL landforms - Abstract
Regional subsurface mapping of glacial depositional systems preserved in buried bedrock paleovalleys, and quantitative analysis of new LiDAR imagery of surface glacial landforms using machine learning techniques, when combined, are powerful tools for assessing the dynamics of the Laurentide Ice Sheet (LIS) during the last (Wisconsinan) glaciation in southern Ontario. While age dating of deposits preserved below Last Glacial Maximum tills (LGM: marine isotope stage (MIS) 2 < c.24 000 years B.P. (ybp)) is still sparse, newly available sedimentological data derived by cored drilling, combined with legacy outcrop data, identify thick (100 m+) successions of glaciolacustrine sediments and a lack of till(s), indicating that the ice sheet margin did not extend beyond the Niagara Escarpment at the western end of Lake Ontario, during the earliest phases of the glaciation (MIS 4) or the ensuing mid-Wisconsinan (MIS 3). Ice was able to extend into New York State blocking the Rome outlet to the Hudson Valley ponding deep proglacial lakes in the glacio-isostatically depressed Huron–Ontario–Erie basins recorded by thick glaciolacustrine sediments in paleovalleys. These were cannibalized by an expanding Late Wisconsinan ice sheet after ∼24 000 ybp recorded by extensive till sheets resting on a marked erosional unconformity, with drumlinized surfaces. Analysis and visualization of LiDAR data identifies discrete statistically validated flow sets of highly elongated streamlined bedforms (mega-scale glacial lineations (MSGLs)). These provide key evidence of a major reorganization of the ice sheet margin during deglaciation into lobate paleo ice streams shortly after 17 400 ybp. MSGLs are cut across earlier LGM drumlinized tills creating widespread "palimpsest" surfaces. At least two principal phases of fast ice flow can be identified, marked by large fluxes of sediment and the rapid building of large gravel and sand-dominated moraine complexes within interlobate depocentres, the largest glacial landforms in southern Ontario. Analysis of LiDAR data further reveals the common presence of DeGeer moraines where ice margins retreated in water, and iceberg scours. Future work using LiDAR mapping has the objective of fully documenting the number, extent, and timing of ice streams to enhance glaciological modelling when the ice sheet rapidly lost mass. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
3. Landform signature of the Laurentide and Cordilleran ice sheets across Alberta during the last glaciation.
- Author
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Atkinson, Nigel, Utting, Daniel J., Pawley, Steven M., and Trenhaile, Alan
- Subjects
GEOLOGICAL surveys ,GLACIAL landforms ,ICE sheets ,GLACIATION ,AERIAL photographs ,SHUTTLE Radar Topography Mission ,DIGITAL elevation models - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2014
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4. Late-glacial lakes in the Thompson Basin, British Columbia: paleogeography and evolution.
- Author
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Johnsen, Timothy F and Brennand, Tracy A
- Subjects
GLACIAL lakes ,GLACIAL landforms ,GEOLOGICAL basins ,STRUCTURAL geology ,VALLEYS - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2004
- Full Text
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5. Late Wisconsinan glaciation of Amund and Ellef Ringnes islands, Nunavut: evidence for the configuration, dynamics, and deglacial chronology of the northwest sector of the Innuitian Ice Sheet.
- Author
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Atkinson, Nigel
- Subjects
ICE sheets ,GLACIERS ,GLACIAL landforms ,ISLANDS - Abstract
Geomorphic and chronologic evidence from Amund and Ellef Ringnes islands documents the configuration, dynamics, and collapse of the northwest sector of the Innuitian Ice Sheet. These data record the inundation of the Ringnes Islands by northwestward-flowing ice from divides spanning the alpine and lowland sectors of the Innuitian Ice Sheet. Ice-flow indicators and granite dispersal along eastern Around Ringnes Island suggest Massey Sound was filled by an ice stream discharging coalescent alpine and lowland ice from Norwegian Bay. In contrast, the interior of Amund Ringnes Island was overridden by predominantly non-erosive, granite-free ice from a divide in the lowland sector of the ice sheet. Glacial landforms on Ellef Ringnes Island record coverage by largely non-erosive ice, but it remains uncertain whether these features relate to northward-flowing lowland ice or a cold-based local ice cap. Deglaciation of the Ringnes Islands commenced -10 000 [sup4]14C years ago. Deglacial dates between 9.7 and 9.2 ka BP record the sequential entry of marine fauna along Massey and Hassel sounds, concomitant with the southward retreat of trunk ice towards Norwegian Bay. These data suggest marine-based trunk glaciers were vulnerable to calving during pre-Holocene eustatic sea-level rise. However, deglacial dates from inner embayments indicate that residual ice caps persisted on Amund and Ellef Ringnes islands for 800 to 1400 14C years after retreat of trunk ice from the adjacent marine channels. Lateral meltwater channels record the subsequent retreat of these ice caps, which became increasingly confined within upland valleys after 8.6 ka BP. [ABSTRACT FROM AUTHOR]
- Published
- 2003
- Full Text
- View/download PDF
6. Net evolution of subglacial sediment transport in the Quebec–Labrador sector of the Laurentide Ice Sheet.
- Author
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Rice, Jessey M., Ross, Martin, Campbell, Heather E., Paulen, Roger C., and McClenaghan, M. Beth
- Subjects
ICE sheets ,GLACIAL landforms ,SEDIMENT transport ,EROSION ,TRANSPORTATION industry ,HEAVY minerals ,BEDROCK - Abstract
The Laurentide Ice Sheet's (LIS) interior had a dynamic polythermal base, but the spatiotemporal variations of subglacial processes related to ice divide migration and other transient changes remain largely unknown, limiting our understanding of regional glacial dynamics. Previous studies focused on the regional glacial landform record, while ice sheet models lacked detailed parameterization within these regions, leading to an overestimation of cold-based subglacial conditions' extent and duration. In this study, glacial sediment dispersal patterns as identified by heavy minerals, clasts, and multivariate statistics of till matrix geochemistry were used to assess ice sheet dynamics within the Quebec–Labrador sector of the LIS. The earliest ice-flow phase produced and transported till across the study area (>175 km). However, major oxide data from till matrix geochemistry show a correlation with underlying bedrock, and this relationship is relatively common in areas of thin till cover and resistant bedrock lithologies. These results suggest a switch from an early phase of widespread erosion and long, sustained sediment transport to one of more limited erosion, perhaps abrasion dominant and shorter transport. Till compositional data and related dispersal patterns add supporting evidence to earlier ice sheet reconstructions based on ice-flow indicators and
10 Be data together suggesting a transition from widespread uniform warm-based conditions during the earliest ice flow, followed by the development of an ice divide, its migration, and more sporadic warm-based conditions. Consequently, a thorough understanding of ice-flow history is essential for ice sheet modelling and future mineral exploration programs in inner ice sheet regions of the LIS. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
7. Onshore–offshore correlation of central Lake Erie glacial deposits.
- Author
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Lewis, C.F.M., Cameron, G.D.M., Barnett, P.J., and Todd, B.J.
- Subjects
GLACIAL lakes ,ICE shelves ,GLACIAL landforms ,DRILL core analysis ,STORM surges ,DEBRIS avalanches - Abstract
Dive observations, echogram transects, core sampling, and a seismic profile revealed that the lake bed of north-central Lake Erie is an extensive terrace cut by storm waves and currents. The terrace is an erosional unconformity on which Late Wisconsinan (Port Bruce and Mackinaw) glacial units crop out. Beds of massive diamictons, and glaciolacustrine sediments containing parallel reflections, crop out alternately from west to east, resulting from an oscillatory ice retreat. These beds correlate with the Port Stanley Drift (Port Bruce phase) and Wentworth Drift (Mackinaw phase) exposed in nearby shore bluffs and onshore moraines. The Port Bruce glacier and earlier readvances formed ice tongues and ice shelves in the central basin. Diamicton layers, some with debris flows, constitute the Port Stanley Till (offshore units M and O). A glaciolacustrine unit N was deposited during Port Bruce glacier recessions. Glaciolacustrine unit P lies between Port Bruce unit O and the Mackinaw Wentworth Till, unit Q. A subsequent glaciolacustrine unit R overlaps unit Q. The onshore Galt and Moffat moraines, composed of Wentworth Till, correlate with ridges of the Norfolk moraine unit Q which extend across Lake Erie between the base of Long Point, Ontario, and Erie, Pennsylvania. The onshore Paris moraine appears to have been eroded on the wave-cut terrace and is evident offshore only near the south shore of Lake Erie. Laminated unit S, younger than unit R, occurs in the western part of central Erie basin, and correlates with overflow of Lake Algonquin from the Huron basin. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
8. A micromorphological perspective on the Neoproterozoic Smalfjord and Mortensnes Formation diamictites—Varangerfjord, Norway.
- Author
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Menzies, John
- Subjects
GLACIAL landforms ,SEDIMENTARY structures ,DEFORMATION potential ,PRECAMBRIAN ,DEBRIS avalanches ,MASS-wasting (Geology) ,MICROSTRUCTURE - Abstract
Many Neoproterozoic diamictites are glacial in origin (Young, G.M. 2018. Precambrian glacial deposits: their origin, tectonic setting, and key role in Earth evolution. In Past glacial environments. 2nd ed. Edited by J. Menzies, and J.J.M. van der Meer. Elsevier. Chapter 2, pp. 17–45. doi:10.1016/B978-0-08-100524-8.00001-4). However, many are thought to be nonglacial mass movement deposits. Discussion on the nature of Neoproterozoic climate change focuses on the controversial origin of diamictite-bearing strata and the criteria to determine the extent and nature, or not, of glacial influence on their deposition. At the macroscale, sediments (diamictites) deposited beneath palaeo-ice masses or debris flows are massive, lack few visible signs of stratification, or deformation signatures. Microscopic investigations have resulted in specific sedimentary structures being identified, indicative of stress during glacial deposition, or developed in transit within mass movements. Case examples derived from the Neoproterozoic in Varanger, Norway have been investigated that provide strain signatures of "unique sequences" of microstructures. Micromorphology, relatively new to Precambrian research, can deliver far greater detail on the depositional and deformation histories recorded by these diamictites than obtained from macroscale studies alone. The technique provides evidence of composite deformation histories of potential glacigenic and nonglacigenic sequences. Many microstructures can be observed in most diamictites. It can be demonstrated that diamictites, both glacigenic and non-glacigenic, contain most of these microstructures in varying levels of abundancy and can be separated on specific "sets" of summative structures present. At Varanger, 12 samples were analyzed for thin sectioning. As illustrative of the thin sections as a whole, 6 are presented here that offer a microscale perspective on the diamictites from this area and establish that both the Smalfjord and Mortensnes Formation diamictites are of glacial terrestrial or subaqueous origin. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
9. Comment on "Converging ice streams: a new paradigm for reconstructions of the Laurentide Ice Sheet in southern Ontario and deposition of the Oak Ridges Moraine"1.
- Author
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Russell, Hazen A.J.
- Subjects
GLACIOLOGY ,GLACIAL landforms ,ICE streams ,ICE sheets - Abstract
The article focuses on the reconstructions of the Laurentide Ice Sheet in southern Ontario and deposition of the Oak Ridges Moraine. Topics discussed include se of geomorphology and legacy data; stratigraphic relationship of the two streamlined till units, valleys, and the Oak Ridges Moraine; and confusion regarding cited references related to the tunnel valleys.
- Published
- 2019
- Full Text
- View/download PDF
10. Meighen Ice Cap: changes in geometry, mass, and climatic response since 1959.
- Author
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Burgess, David O. and Danielson, Bradley D.
- Subjects
ICE caps ,ATMOSPHERIC temperature ,REMOTE sensing ,MASS measurement ,GEOMETRY ,GLACIAL landforms - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2022
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11. Alpine glacial geology of the Tablelands, Gros Morne National Park, Newfoundland.
- Author
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Osborn, Gerald, Spooner, Ian, Gosse, John, and Clark, Doug
- Subjects
PLEISTOCENE paleoclimatology ,GLACIAL climates ,GLACIOLOGY ,PERMAFROST ,GLACIAL landforms ,ROCK glaciers ,MOUNTAIN climate ,NATIONAL parks & reserves - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2007
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12. The late Quaternary stratigraphic record northwest of Montréal: regional ice-sheet dynamics, ice-stream activity, and early deglacial events.
- Author
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Ross, Martin, Parent, Michel, Benjumea, Beatriz, and Hunter, James
- Subjects
GEOMORPHOLOGY ,GLACIAL landforms ,LANDFORMS ,VALLEYS ,GLACIAL lakes ,EROSION ,SEDIMENTATION & deposition - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2006
- Full Text
- View/download PDF
13. Insights into the Connaught sequence of the Timiskaming varve series from Frederick House Lake, northeastern Ontario.
- Author
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Brooks, Gregory R.
- Subjects
GLACIAL lakes ,GLACIAL landforms ,DRILL core analysis ,LAKES ,LAKE sediments - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2021
- Full Text
- View/download PDF
14. Major end moraines of Younger Dryas age on Wollaston Peninsula, Victoria Island, Canadian Arctic: implications for paleoclimate and for formation of hummocky moraine: Discussion.
- Author
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Rampton, Vernon N
- Subjects
YOUNGER Dryas ,MORAINES ,GLACIAL landforms ,ROSACEAE ,ICE - Abstract
Discusses the implications for paleoclimate and for formation of hummocky moraine of the major end moraines of Younger Dryas age on Wollaston Peninsula, Victoria Island and the Canadian Arctic. Analysis of ice-cored topography; Details on the till layers forming the cap of the ice-cored moraines on the Tuktoyaktuk Peninsula; Evidence that shows ice-cored moraines would become classical hummocky moraine.
- Published
- 2001
- Full Text
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15. Regional stagnation of the western Keewatin ice sheet and the significance of meltwater corridors and eskers, northern Canada.
- Author
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Sharpe, D.R., Lesemann, J.-E., Knight, R.D., and Kjarsgaard, B.A.
- Subjects
MELTWATER ,ICE sheets ,DRUMLINS ,GLACIAL landforms ,EROSION ,MORAINES ,GLACIAL melting ,SEDIMENTATION & deposition - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2021
- Full Text
- View/download PDF
16. Converging ice streams: an unreasonable hypothesis for deposition of the Oak Ridges Moraine, southern Ontario.
- Author
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Sharpe, David R. and Russell, Hazen A.J.
- Subjects
ICE streams ,GLACIAL landforms ,MORAINES ,DIGITAL elevation models ,SEQUENCE stratigraphy - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2020
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17. Geomorphic diversity and complexity of the inner shelf, Canadian Arctic Archipelago, based on LiDAR and multibeam sonar surveys.
- Author
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Shaw, John, Potter, D. Patrick, and Wu, Yongsheng
- Subjects
GLACIAL landforms ,LIDAR ,SONAR ,SEA level ,ARCHIPELAGOES ,GAS hydrates ,BEACH ridges - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2020
- Full Text
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18. Reply to the comment by H.A.J. Russell on "Converging ice streams: a new paradigm for reconstructions of the Laurentide Ice Sheet in southern Ontario and deposition of the Oak Ridges Moraine"1.
- Author
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Sookhan, Shane, Eyles, Nicholas, and Arbelaez-Moreno, Lina
- Subjects
GLACIAL landforms ,ICE streams ,ICE sheets ,GLACIOLOGY - Published
- 2019
- Full Text
- View/download PDF
19. Borehole geophysical log signatures and stratigraphic assessment in a glacial basin, southern Ontario.
- Author
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Russell, Hazen A. J., Crow, Heather L., Hunter, James A., Olson, Laura C., and Pugin, André J.-M.
- Subjects
BOREHOLES ,GEOPHYSICAL well logging ,GLACIAL landforms ,STRATIGRAPHIC geology - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2018
- Full Text
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20. Conceptual hydrogeological model of the Yonge Street Aquifer, south-central Ontario: a glaciofluvial channel-fan setting.
- Author
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Gerber, Richard E., Holysh, Steve, Sharpe, David R., Russell, Hazen A.J., and Khazaei, Esmaeil
- Subjects
AQUIFERS ,HYDROGEOLOGICAL modeling ,GLACIAL landforms ,FLUVIAL geomorphology ,YONGE Street (Toronto, Ont.) - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2018
- Full Text
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21. Holocene glacier history of Frank Mackie Glacier, northern British Columbia Coast Mountains.
- Author
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St-Hilaire, Vikki M. and Smith, Dan J.
- Subjects
GLACIERS ,CRYOSPHERE ,MORAINES ,GLACIAL landforms - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2017
- Full Text
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22. A flowline map of glaciated Canada based on remote sensing data<A></A>.
- Author
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Shaw, John, Sharpe, Davis, and Harris, Jeff
- Subjects
GLACIAL landforms ,REMOTE sensing ,ICE sheets ,CARTOGRAPHY - Abstract
The map A flowline map of glaciated Canada based on remote sensingdata presents flowlines for the former Laurentide and Cordilleran ice sheets based on flow indicators derived from aggregated, flow-parallel landforms — drumlins and crag and tails, fluting, sinuous ridges and furrows, and rises. An extensive review introduces the concepts and evolution of flowline mapping at continental-ice-sheet and regional scales, emphasizing the use of new remote sensing data. Coherent, glaciologically plausible sets of flowlines mapped as flow tracts reflect large-scale flow structure in the paleo-ice sheets and demarcate fields of flow-parallel bedforms. In addition to flow reconstruction, mapped distributions of fields of glacial terrain types — hummocky terrain, Rogen terrain, and bedrock-dominant terrain — increase our power to interpret flowlines and, in turn, give evidence on the genesis of these terrains. End moraines and eskers also aid map interpretation. Landsat 7 Enhanced Thematic Mapper+ (ETM+) satellite images and Shuttle Radar Topography Mission (SRTM) hill shades provide the basic information for this flowline mapping in a Geographical Information System (ArcMap). Information on the Flowline Map allows us to develop conceptual models of ice sheets and to appreciate regional constraints on applications in mineral exploration, in aggregate and groundwater discovery and assessment, in soil and landform genesis, and in glaciology, paleoclimatology, and paleoceanography. « La carte de l’écoulement glaciaire au Canada, tracée à partir de données de télédétection présente les directions d’écoulement des anciens inlandsis Laurentidien et de la Cordillère basées sur des indicateurs d’écoulement dérivés de formes de terrain regroupées parallèles à l’écoulement — des drumlins, des traînées morainiques à l’aval d’un nez rocheux, des rainures glaciaires, des crêtes et des sillons sinueux et des soulèvements. Une révision exhaustive présente les concepts et l’évolution de la cartographie des lignes d’écoulement à l’échelle régionale et des inlandsis continentaux, mettant l’accent sur l’utilisation des nouvelles données de télédétection. Des ensembles cohérents, et plausibles d’un point de vue de la glaciologie, de lignes d’écoulement cartographiés en tant qu’étendues d’écoulement reflètent une structure d’écoulement à grande échelle dans les paléo-inlandsis et ils délimitent des champs de morphologie de fond parallèles à l’écoulement. En plus de la reconstruction de l’écoulement, des distributions cartographiées de champs de types de terrains glaciaires — terrain en bosses et creux, terrain de Rogen et un terrain dominé par le roc du socle — rehaussent notre capacité d’interprétation les lignes d’écoulement et, donc, de fournir des évidences de la genèse de ces terrains. Les moraines frontales et les eskers peuvent aussi aider à interpréter les cartes. Les images satellites Landsat 7 Enhanced Thematic Mapper+ (ETM+) et le relief ombragé fourni par la Shuttle Radar Topography Mission fournissent l’information de base pour cette cartographie des lignes d’écoulement dans un système d’information géographique (ArcMap). L’information contenue dans la carte d’écoulement nous permet de développer des modèles conceptuels des inlandsis et d’appliquer des limites régionales sur les applications en exploration minérale pour la découverte et l’évaluation de l’eau souterraine et des agrégats, dans la genèse des sols et des formes de terrain ainsi qu’en glaciologie, en paléoclimatologie et en paléo-océanographie. [ABSTRACT FROM AUTHOR]
- Published
- 2010
23. Prediction of decadal slope changes in Canada by glacial isostatic adjustment modelling.
- Author
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Van der Wal, Wouter, Braun, Alexander, Wu, Patrick, and Sideris, Michael G.
- Subjects
GLACIAL landforms ,PLEISTOCENE stratigraphic geology ,ICE sheets ,VISCOSITY - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2009
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24. Landform assemblages produced by the Laurentide Ice Sheet in northeastern British Columbia and adjacent Northwest Territories — constraints on glacial lakes and patterns of ice retreat.
- Author
-
Bednarski, Jan M.
- Subjects
LANDFORMS ,GLACIERS ,GLACIAL landforms ,ICE sheets ,ICE caps ,LAKES ,SURFACE of the earth - Abstract
The Laurentide Ice Sheet reached the Canadian Cordillera during the last glacial maximum in northeastern British Columbia and adjacent Northwest Territories and all regional drainage to unglaciated areas in the north was dammed by the ice. Converging ice-flow patterns near the mountain front suggest that the Laurentide Ice Sheet likely coalesced with the Cordilleran Ice Sheet during the last glaciation. With deglaciation, the ice masses separated, but earlier ice retreat in the south meant that meltwater pooled between the mountain front and the Laurentide margin. The level of the flooding was controlled by persistent ice cover on the southern Franklin Mountains. Glacial Lake Liard formed when the Laurentide Ice Sheet retreated east of the southern Liard Range and, at its maximum extent, may have impounded water at least as far south as the Fort Nelson River. Deglaciation of the plains was marked by local variations in ice flow caused by a thin ice sheet becoming more affected by the topography and forming lobes in places. These lobes caused diversions in local drainage readily traced by abandoned meltwater channels. Radiocarbon ages from adjacent areas suggest the relative chronology of deglaciation presented here occurred between 13 and 11 ka BP. L’Inlandsis laurentidien a atteint la Cordillère canadienne durant le dernier maximum glaciaire dans le nord-est de la Colombie-Britannique et les Territoires du Nord-Ouest adjacents et tout le drainage régional vers des secteurs non glaciés au nord était retenu par la glace. Des patrons d’écoulement glaciaire convergents à proximité du front des montagnes suggèrent que l’Inlandsis laurentidien se soit probablement uni avec la glace de la Cordillère au cours de la dernière glaciation. Lors de la déglaciation, les masses de glace se sont séparées. Cependant, le retrait antérieur au sud signifiait une accumulation de l’eau de fonte entre le front des montagnes et la bordure laurentidienne. Le niveau d’inondation était contrôlé par la surface gelée persistante sur les monts Franklin Sud. Le lac glaciaire Liard s’est formé lorsque l’Inlandsis laurentidien a reculé à l’est de la chaîne Liard sud et, à son étendue maximale, il pourrait avoir endigué de l’eau au moins aussi au sud que la rivière Fort Nelson. La déglaciation des plaines a été marquée par des variations locales de l’écoulement glaciaire causées par le fait qu’une couche de glace mince est plus affectée par la topographie et forme des lobes à certains endroits. Ces lobes ont dévié le drainage local facilement tracé par les chenaux abandonnés d’eau de fonte. Les âges radiocarbone de secteurs adjacents suggèrent que la chronologie relative de déglaciation présentée ici ait eu lieu entre 13 et 11 ka avant le présent. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
25. Luminescence dating of mid- to Late Wisconsinan aeolian sand as a constraint on the last advance of the Laurentide Ice Sheet across the Tuktoyaktuk Coastlands, western Arctic Canada.
- Author
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Murton, Julian B., Frechen, Manfred, and Maddy, Darrel
- Subjects
GLACIOLOGY ,ICE sheets ,GLACIAL climates ,ROCK-forming minerals ,GLACIAL landforms ,CARBON isotopes ,RADIOCARBON dating - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2007
- Full Text
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26. Late Ordovician - Early Silurian cryptospore occurrences on Anticosti Island (Île d'Anticosti), Quebec, Canada.
- Author
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Richardson, Jeffery G. and Ausich, William I.
- Subjects
PLANT spores ,SILURIAN stratigraphic geology ,ORDOVICIAN stratigraphic geology ,CRYPTOBIOSIS ,AGRICULTURAL wastes ,GLACIAL landforms ,PALYNOLOGY - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2007
- Full Text
- View/download PDF
27. Nass River on the move: radar facies analysis of glaciofluvial sedimentation and its response to sea-level change in northwestern British Columbia.
- Author
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McCuaig, S. J. and Roberts, M. C.
- Subjects
RIVERS ,GLACIAL landforms ,SEDIMENTATION & deposition ,SEDIMENTATION analysis ,RADAR in earth sciences ,ABSOLUTE sea level change ,DELTAS ,EARTH sciences - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2006
- Full Text
- View/download PDF
28. A record of post-glacial moraine deposition and tephra stratigraphy from Otokomi Lake, Rose Basin, Glacier National Park, Montana.
- Author
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MacLeod, David Matthew, Osborn, Gerald, and Spooner, Ian
- Subjects
NATIONAL parks & reserves ,MORAINES ,GLACIAL landforms ,MAGNETIC susceptibility ,LANDFORMS ,AGRICULTURAL engineering - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2006
- Full Text
- View/download PDF
29. A multi-proxy lithostratigraphic record of Late Glacial and Holocene climate variability from Piper Lake, Nova Scotia.
- Author
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Spooner, Ian S., MacDonald, Ian, Beierle, Brandon, and Jull, A.J. Timothy
- Subjects
GLACIAL climates ,CLIMATE change ,PALEOCLIMATOLOGY ,GLACIAL lakes ,GLACIAL landforms ,OCEAN-atmosphere interaction ,LAKES ,ICE caps ,ICE sheets ,ATMOSPHERIC pressure - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2005
- Full Text
- View/download PDF
30. Pleistocene volcanic damming of Yukon River and the maximum age of the Reid Glaciation, west-central Yukon.
- Author
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Huscroft, Crystal A., Ward, Brent C., Barendregt, René W., Opdyke, Neil D., and Jackson Jr., Lionel E.
- Subjects
PLEISTOCENE stratigraphic geology ,GLACIAL landforms ,RADIONUCLIDE imaging - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2004
- Full Text
- View/download PDF
31. Lake Terrell upland glacial resurgences and implications for late-glacial history, northwestern Washington State, U.S.A.
- Author
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Kovanen, Dori J. and Slaymaker, Olav
- Subjects
GEOMORPHOLOGY ,MORAINES ,GLACIAL landforms ,STRATIGRAPHIC geology - Abstract
Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2003
- Full Text
- View/download PDF
32. The lower Proterozoic Fern Creek Formation, northern Michigan: mineral and bulk geochemical evidence for its glaciogenic origin.
- Author
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Argast, Anne
- Subjects
GLACIAL lakes ,GLACIAL landforms ,SEDIMENTS ,SEDIMENTATION & deposition - Abstract
Bulk chemical data indicate the Fern Creek Formation (Early Proterozoic, Marquette Range Supergroup, Lower Chocolay Group) originated as a glacial till, resolving an old argument about the correct interpretation for diamictite-containing units within the formation. There are poor correlations among SiO[sub 2,] Al[sub 2] O[sub 3,] and K[sub 2] O, and the chemical index of alteration averages 55. These are qualities characteristic of tills and other sediments accumulated in the absence of chemical weathering and transport-induced sorting and inconsistent with an origin as a fluvial deposit (the principal alternate hypothesis). The Archean Carney Lake Gneiss might be the source for at least the lower portions of the Fern Creek Formation. Compositions are similar, and rare earth element trends in the Fern Creek Formation are consistent with derivation from an Archean high-grade terrane. Pegmatites in the gneiss could be the source for monazite, huttonite, and an unnamed fluor-hydroxy-rare earth mineral that occurs in the midsection of the Fern Creek Formation. In addition, mineral and bulk chemical trends are consistent with models involving deep erosion of a complex Archean source, similar to models previously developed for Gowganda tills in the Huronian Supergroup. Samples of the Sturgeon River Quartzite occurring above the Fern Creek Formation were also analyzed. The bulk chemistry is consistent with a well-sorted, supermature quartz arenite.Des données chimiques brutes indiquent que la Formation de Fern Creek (Protérozoïque précoce, Supergroupe de Marquette Range, Groupe de Chocolay inférieur) a débuté en tant que till glaciaire, mettant ainsi fin à un vieil argument à propos de l'interprétation juste des unités diamictites à l'intérieur de la formation. Les corrélations entre SiO[sub 2] , Al[sub 2] O[sub 3] et K[sub 2] O sont faibles et l'indice d'altération chimique a une moyenne de 55. Ces points sont caractéristiques de tills et d'autres sédiments accumulés sans altération chimique ni tri effectué par le transport; ils ne supportent pas une origine de dépôt fluviatile (l'autre hypothèse principale). Au moins les portions inférieures de la Formation de Fern Creek pourraient provenir du gneiss de Carney Lake (Archéen). Les compositions sont semblables et les tendances des éléments des terres rares dans la Formation de Fern Creek sont compatibles avec une dérivation d'un ancien terrane archéen élevé. Les pegmatites dans le gneiss pourraient être la source de la monazite, de la huttonite et d'un minéral hydroxy-fluor-terre rare, jusqu'à présent sans nom, qui se trouve dans la section médiane de la Formation de Fern Creek. De plus, les tendances minérales et chimiques brutes concordent avec des modèles impliquant une érosion profonde d'une source archéenne complexe, semblables aux modèles antérieurement développés pour les tills du Gowganda dans le Supergroupe de l'Huronien. Des échantillons du quartzite de Sturgeon River se trouvant au-dessus de la Formation de Fern Creek ont aussi été analysés. La chimie de la masse concorde avec une arénite quartzique, bien triée et supermature. [Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]
- Published
- 2002
- Full Text
- View/download PDF
33. Holocene and latest Pleistocene fluctuations of Stutfield Glacier, Canadian Rockies.
- Author
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Osborn, G D, Robinson, B J, and Luckman, B H
- Subjects
GLACIERS ,MOUNTAINS ,MORAINES ,GLACIAL landforms ,RIVERS - Abstract
The Holocene and late glacial history of fluctuations of Stutfield Glacier are reconstructed using moraine stratigraphy, tephrochronology, and dendroglaciology. Stratigraphic sections in the lateral moraines contain tills from at least three glacier advances separated by volcanic tephras and paleosols. The oldest, pre-Mazama till is correlated with the Crowfoot Advance (dated elsewhere to be Younger Dryas equivalent). A Neoglacial till is found between the Mazama tephra and a paleosol developed on the Bridge River tephra. A log dating 2400 BP from the upper part of this till indicates that this glacier advance, correlated with the Peyto Advance, culminated shortly before deposition of the Bridge River tephra. Radiocarbon and tree-ring dates from overridden trees exposed in moraine sections indicate that the initial Cavell (Little Ice Age (LIA)) Advance overrode this paleosol and trees after A.D. 1271. Three subsequent phases of the Cavell Advance were dated by dendrochronology. The maximum glacier extent occurred in the mid-18th century, predating 1743 on the southern lateral, although ice still occupied and tilted a tree on the north lateral in 1758. Subsequent glacier advances occurred ca. 1800–1816 and in the late 19th century. The relative extent of the LIA advances at Stutfield differs from that of other major eastward flowing outlets of the Columbia Icefield, which have maxima in the mid–late 19th century. This is the first study from the Canadian Rockies to demonstrate that the large, morphologically simple, lateral moraines defining the LIA glacier limits are actually composite features, built up progressively (but discontinuously) over the Holocene and contain evidence of multiple Holocene- and Crowfoot-age glacier advances.La stratigraphie des moraines, la téphrochronologie et la dendroglaciologie des moraines ont servi à reconstruire les fluctuations à l'Holocène et au cours de l'histoire glaciaire tardive du glacier Stutfield. Les sections stratigraphiques dans les moraines latérales contiennent des tills d'au moins trois avancées glaciaires séparées par des tephras volcaniques et des paléosols. Le plus ancien, le till pré-Mazama, est corrélé à l'avancée Crowfoot (dont on a déterminé l'âge ailleurs comme étant un équivalent du Dryas récent). Un till de l'époque néo-glaciaire se retrouve entre le tephra Mazama et un paléosol développé sur le tephra de Bridge River. Un billot, daté 2400 BP, provenant de la partie supérieure de ce till, indique que cette avancée glaciaire, corrélée à l'avancée de Peyto, a culminé peu de temps avant la déposition du tephra de Bridge River. Des datations au [sup 14] C et des séries chronlogiques provenant d'arbres recouverts, puis exposés dans des sections de moraine, indiquent que l'avancée Cavell initiale (petit âge glaciaire) a chevauché ce paléosol et les arbres après l'an 1271. La dendrochronologie a permis la datation de trois phases subséquentes de l'avancée Cavell. L'étendue glaciaire maximale eut lieu au milieu du 18e siècle, avant 1743 sur le coté sud bien que la glace fut encore présente sur le côté nord et y ait basculé un arbre en 1758. Des avancées glaciaires subséquentes ont eu lieu vers 1800-1816 et vers la fin du 19e siècle. L'étendue relative des avancées du petit âge glaciaire à Stutfield diffère de celles d'autres glaciers majeurs du champ de glace Columbia s'écoulant vers l'est et qui ont eu leur maximum dans la deuxième moitié du 19e siècle. Cette étude est la première provenant des Rocheuses canadiennes à démonter que les grandes moraines latérales morphologiquement simples définissant les limites du glacier au petit âge glaciaire sont en fait des éléments composites, développés progressivement (mais de façon discontinue) tout au cours de l'Holocène et qu'elles contiennent des évidences d'avancées glaciaires multiples d'âge Holocène et Crowfoot.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]
- Published
- 2001
- Full Text
- View/download PDF
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