Late Quaternary Sea Level Changes on Brock and Prince Patrick Islands
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Document generated on 09/30/2021 4:56 p.m. Géographie physique et Quaternaire Late Quaternary Sea Level Changes on Brock and Prince Patrick Islands, Western Canadian Arctic Archipelago Les changements du niveau marin au Quaternaire supérieur, dans les îles Brock et du Prince-Patrick, dans l’ouest de l’archipel arctique canadien Veränderungen des Meeresniveaus im späten Quaternär auf den lnseln Brock und Prince Patrick, arktisches Archipel im Westen Kanadas Douglas A. Hodgson, Robert B. Taylor and John G. Fyles Volume 48, Number 1, 1994 Article abstract Emerged shorelines are few and poorly defined on Prince Patrick and Brock URI: https://id.erudit.org/iderudit/032973ar islands. The sparse radiocarbon dates show emergence of only 10 m through DOI: https://doi.org/10.7202/032973ar the Holocene on the Arctic Ocean coast, increasing to 20 m 100 km to the east. Hence, from Brock Island, representative of westernmost coasts, the sea level See table of contents curve since the latest Pleistocene has a very low gradient, whereas on eastern Prince Patrick Island the curve takes the more typical exponential form. A decline in isobases towards the west is thus registered. Drowned estuaries, Publisher(s) breached lakes, and coastal barriers, particularly in southwest Prince Patrick Island, suggest that the sea is now transgressing at a rate that decreases Les Presses de l'Université de Montréal towards the north end of the island, hence there is also a component of tilt to the south. Delevelling is assumed to result from undefined ice loads, but may ISSN have a tectonic component. The sole prominent raised marine deposit is a ridge probably built in a period of more mobile sea ice, possibly at a time of 0705-7199 (print) stable or slightly rising sea level in the middle or early Holocene. It winds 1492-143X (digital) discontinuously along several hundred of kilometres of the shores of the Arctic Ocean and connecting channels, declining to the south. Explore this journal Cite this article Hodgson, D. A., Taylor, R. B. & Fyles, J. G. (1994). Late Quaternary Sea Level Changes on Brock and Prince Patrick Islands, Western Canadian Arctic Archipelago. Géographie physique et Quaternaire, 48(1), 69–84. https://doi.org/10.7202/032973ar Tous droits réservés © Les Presses de l'Université de Montréal, 1994 This document is protected by copyright law. Use of the services of Érudit (including reproduction) is subject to its terms and conditions, which can be viewed online. https://apropos.erudit.org/en/users/policy-on-use/ This article is disseminated and preserved by Érudit. Érudit is a non-profit inter-university consortium of the Université de Montréal, Université Laval, and the Université du Québec à Montréal. Its mission is to promote and disseminate research. https://www.erudit.org/en/ Géographie physique et Quaternaire, 1994, vol. 48, n° 1, p. 69-84, 10 fig., 1 tabl. LATE QUATERNARY SEA LEVEL CHANGES ON BROCK AND PRINCE PATRICK ISLANDS, WESTERN CANADIAN ARCTIC ARCHIPELAGO* Douglas A. HODGSON, Robert B. TAYLOR and John G. FYLES, Geological Survey of Canada : first and third authors, Terrain Sciences Division, 601 Booth Street, Ottawa, Ontario K1A OE8; second author, Atlantic Geoscience Centre, Bedford Institute of Oceanography, Box 1006, Dartmouth, Nova Scotia B2Y 4A2. ABSTRACT Emerged shorelines are few RÉSUMÉ Les changements du niveau ZUSAMMENFASSUNG Verànderungen and poorly defined on Prince Patrick and marin au Quaternaire supérieur, dans les des Meeresniveaus im spàten Quaternar auf Brock islands. The sparse radiocarbon dates îles Brock et du Prince-Patrick, dans l'ouest den lnseln Brock und Prince Patrick, arktis- show emergence of only 10 m through the de l'archipel arctique canadien. Les rivages ches Archipel im Westen Kanadas. Auf- Holocene on the Arctic Ocean coast, increa émergés sont peu nombreux et mal définis getauchte Uferlinien sind rar und kaum fest- sing to > 20 m 100 km to the east. Hence, dans les îles Brock et du Prince-Patrick. Les gelegt auf den Insein Prince Patrick und from Brock Island, representative of western rares datations au radiocarbone n'indiquent Brock. Die spàrlichen Radiokarbondaten zei- most coasts, the sea level curve since the qu'une émergence de 10 m des côtes de gen im Holozàn ein Auftauchen an der ark- latest Pleistocene has a very low gradient, l'océan Arctique, au cours de l'Holocène, tischen Ozeankùste von nur 10 m, das whereas on eastern Prince Patrick Island the s'accroissant à > 20 m, à 100 km vers l'est. 100 km ostlich auf > 20 m ansteigt. So hat curve takes the more typical exponential Ainsi, à partir des côtes de l'île Brock, repré die Meeresniveaukurve von der lnsel Brock sentatives de la partie la plus occidentale, le form. A decline in isobases towards the west ausgehend, welche fur die am westlichsten is thus registered. Drowned estuaries, brea niveau marin depuis le Pleistocene supé gelegenen Kùsten reprâsentativ ist, seit dem ched lakes, and coastal barriers, particularly rieur a un très faible gradient; par contre, spàtesten Pleistozàn ein sehr niedriges in southwest Prince Patrick Island, suggest dans la partie est de l'île du Prince-Patrick, la Gefàlle, wohingegen die Kurve im ôstlichen that the sea is now transgressing at a rate courbe du niveau marin a un caractère nette Teil der Insel Prince Patrick die mehr typis- that decreases towards the north end of the ment exponentiel. On enregistre donc un che exponentielle Form hat. Man registriert island, hence there is also a component of tilt abaissement des isobases vers l'ouest. Les also eine Senkung der Isobasen nach to the south. Delevelling is assumed to result estuaires submergés, les lacs ébréchés et Westen hin. Ùberflutete Gezeitenmûn- from undefined ice loads, but may have a les barrières littorales, surtout dans le sud- dungen, geschartete Seen und Kùsten- tectonic component. The sole prominent rai ouest de l'île du Prince-Patrick, semblent sed marine deposit is a ridge probably built indiquer qu'il y a actuellement transgression damme, besonders im Westen der Prince in a period of more mobile sea ice, possibly marine à un taux qui décroît vers le nord de Patrick-lnsel, lassen vermuten, dassjetztdie at a time of stable or slightly rising sea level l'île; il y a donc aussi inclinaison vers le sud. horizontale Verlagerungsrate des Meeres in the middle or early Holocene. It winds dis On présume que le dénivelé découle de zum Nordende der Insel hin abnimmt, fol- continuous^ along several hundred of kilo charges glaciaires indéterminées, mais peut glich gibt es auch eine Neigung nach Sùden metres of the shores of the Arctic Ocean and aussi avoir une composante tectonique. Le hin. Man fùhrt die Verstellung auf unbes- connecting channels, declining to the south. seul dépôt marin soulevé d'importance est timmte Eisfrachten zurùck, doch kônnte sie une crête probablement édifiée alors que la eine tektonische Komponente haben. Die glace de mer était plus mobile, pendant que einzige herausragende marine Auftauch- le niveau marin était stable ou légèrement en ablagerung ist eine Schwelle, die wohl in hausse, au début ou au milieu de l'Holocène. einer Période mobileren Meereises gebaut La crête serpente de façon irrégulière sur wurde, môglicherweise in einer Zeit mit sta- plusieurs centaines de kilomètres de côtes bilem oder gering ansteigendem Meeres- de l'océan Arctique et de chenaux adjacents, niveau im mittleren oderfrùhen Holozàn. Sie tout en s'abaissant vers le sud. windet sich diskontinuierlich ùber mehrere hundert Kilometer an den Kùsten des ark- tischen Ozeans und der angrenzenden Kanàle entlang und senkt sich nach Sùden. * Geological Survey of Canada Contribution N0 43692 Manuscrit reçu le 23 février 1993; manuscrit révisé accepté le 8 novembre 1993 70 D. A. HODGSON, R. B. TAYLOR and J. G. FYLES INTRODUCTION r~~~i ° 300 km / ' i ' I There is a general perception, based on few published / / observations, that on the westernmost Canadian Arctic LJ^-^ islands (I.e. those bordering the Arctic Ocean, from Banks to ^ Axel Meighen islands, Fig. 1) little emergence and perhaps some Meighen Heiberg 0° lsland submergence of coasts has occurred during the Holocene. In ' Island / „ this respect, these islands are unlike most of the Arctic, where s "'Fay Is flights of raised beaches record continuous emergence Borden .. s" Island P^ Ellef reaching tens or hundreds of metres above sea level (asl) Brock ^^ Ringnes (Bird, 1967). This paper presents the first compilation of pub Prince Island/ Island lished radiocarbon dates from the westernmost Queen o Patrick / s Elizabeth Islands, together with new information on Holocene V Island -xy y,^ and latest Pleistocene sea levels from Brock and Prince Patrick islands (Fig. 1). We also describe a unique paleo- ?5 <% / shore marker, generally referred to in this paper as 'the ridge'. <&,•<P - This prominent feature, built by sea ice, parallels the coast for / Melville / Island more than one hundred kilometres. For most of its length the Resolute ridge lies beyond conceivable reach of recent ice push. The I results of these investigations of sea level change are com Beaufort . o/ pared with published models of marine limit and isobases for Sea £& Banks the Arctic. y Island / Stefansson (1921) first remarked on the drowned creek / / estuaries on Banks Island; subsequently Manning (1956) rec / ognized that peat submerged at normal high tide suggested Victoria that the west coast of Banks Island is sinking, while Tozer Island (1956) commented on the scarcity of emerged strandlines on Prince Patrick Island. Craig and Fyles (1960), on the basis of JSO' these and their own observations, suggested a transgression FIGURE 1. Location of western Canadian Arctic Archipelago, resulting from an eustatic sea level rise accompanying melt Arctic Coastal Plain and study area. ing of the last ice sheets. They showed a drowned coastline, Localisation de l'archipel arctique occidental, de la plaine côtière arc from Yukon to Borden Island (Craig and Fyles, 1965, Fig.