Wisconsinan Late‐glacial environmental chage in Québec: A regional synthesis

Richard, Pierre J. H.

doi:10.1002/jqs.3390090212

Cited by 24 publications

(12 citation statements)

References 36 publications

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“…The Picea recurrence at 9650 BP corresponds with the PB cooling event. This early Holocene climate oscillation has also been documented, mostly from palynological evidence, along the Great Lakes}St. Lawrence waterway (Richard et al, 1992;Anderson and Lewis, 1992;Richard, 1994) and in Newfoundland (Anderson and Macpherson, 1994). At TMP, there are no indications of change in soil erosion from lithology and elemental geochemistry during this period, probably indicating existence of a stabilized forest-covered landscape in the watershed.…”

Section: Regional Vegetation Landscape and Lake Developmentmentioning

confidence: 95%

Ecosystem response to Lateglacial and early Holocene climate oscillations in the Great Lakes region of North America

2000

Quaternary Science Reviews

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Fossil pollen, plant macrofossils, gastropods, and elemental and stable-isotope geochemistry in a sediment core from Twiss Marl Pond, southern Ontario, Canada, were used to document climate oscillations during the Last Glacial}Interglacial transition ( &13,000}8500 C BP) and understand their ecological e!ects. Chronology was provided by AMS C dating and regional pollen correlation. Oxygen isotope ( O) results from mollusc shells, Chara-encrustations and bulk carbonates show a classic climate sequence of a warm B+lling}Aller+d (BOA) at &12,500}10,920 C BP, a cold Younger Dryas (YD) at 10,920}10,000 C BP, the Holocene warming at 10,000 C BP, a brief Preboreal Oscillation (PB) at 9650 C BP, and a possible Gerzensee/Killarney (G/K) cooling shortly before 11,000 C BP.Clay sediments at the base of the core contain high herb and shrub pollen and abundant arctic/alpine plant macrofossils, indicating a treeless tundra with severe soil erosion in watershed. During the BOA warm period, authigenic marl began to be deposited, and Picea woodland became established. The establishment of Picea woodland after peaks of O and of carbonate accumulation suggests a lagged response of upland vegetation to BOA warming. In contrast, the occurrence of warmth-loving aquatics Najas yexilis and Typha latifolia at that time indicates sensitive responses of aquatic plants. The YD cooling is indicated by a &1.5 negative excursion in O, an increase in minerogenic matter and higher concentrations of erosion-derived elements (Al, Na, K, Ti and V). Pollen data show no forest transformation in response to YD cooling, which is attributed to the insensitive nonecotonal vegetation at that time. However, more openings in the forests and increased erosion in the watershed are indicated by a slight increase of herb pollen, high concentrations of erosion elements and a Pediastrum peak. The onset of the Holocene was marked by an abrupt increase of 2 in O and the replacement of Picea woodland by Pinus-dominated forest. The Picea recurrence at 9650 C BP demonstrates sensitive response of ecotonal vegetation to the PB climate oscillation, which is also indicated by 0.4 negative excursion of O. These new results suggest the importance of multiproxy records for reliable paleoclimate reconstruction.Reevaluation and revised chronologies of previously published sites (Gage Street, and Nichols Brook) in the eastern Great Lakes region show their major O shifts correlative to the YD and PB oscillations as documented from Twiss Marl Pond and nearby Crawford Lake. The sequence and magnitude of climatic oscillations from these sites match in detail with records from the Atlantic Seaboard, suggesting that these oscillations are an expression of broad-scale, probably global, climate change rather than local meltwater-induced climate cooling.

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Section: Regional Vegetation Landscape and Lake Developmentmentioning

confidence: 95%

Ecosystem response to Lateglacial and early Holocene climate oscillations in the Great Lakes region of North America

2000

Quaternary Science Reviews

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“…Reversals in the warming trend from late Alleröd to YD are not apparent on pollen diagrams of southern Québec, because the Saint-Narcisse Event occurred during the long tundra phase of pollen diagrams established in Appalachian sites (Mott, 1977;Richard, 1977Richard, , 1994aRichard, , 1994b and in the Laurentians south of the moraine outer limit (Labelle and Richard, 1981;Mott and Farley-Gill, 1981).…”

Section: Relation Of the Saint-narcisse Morainic Complex With Youngermentioning

confidence: 99%

The Saint-Narcisse morainic complex and early Younger Dryas events on the southeastern margin of the Laurentide Ice Sheet

Occhietti

2010

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The Saint-Narcisse morainic complex extends over 750 km along the southern margin of the Laurentian Highlands in Québec, north of the St. Lawrence Valley, between the Ottawa and Saguenay Rivers. To the east, the Laurentide Ice Sheet margin was located in the present St. Lawrence Estuary. To the west, the morainic complex is extended 235 km west of the Ottawa River to the Algonquin Highlands, in Ontario. The general outline of the morainic complex comprises large lobes and reentrants, related to major topographic features. In the lower Saint-Maurice River area, the moraine is composed of reworked clay and till and proximal glaciomarine deposits (Yamachiche Diamicton) and melt-out till and ice-marginal outwash (Charette Drift). The Saint-Narcisse Event can be subdivided in several phases: local readvance in low areas, main phase at the origin of the Saint-Narcisse Moraine s.s., melting-out of the marginal ice with compressive structures and large proglacial outwash features, and slow retreat with secondary ridges. The accuracy of the chronological data is limited by several factors: and a floating chronology is proposed. Two landmarks constrain the age and range of duration of the main Saint-Narcisse phase. The main ridge deposition occured after the onset, ca. 12.9 cal ka, of Champlain Sea in the St. Lawrence Valley, and a rapid ice retreat on the southern edge of the Laurentians. It ended before the drawdowm, in the Lake Huron basin, of Glacial Lake Algonquin ca. 12.5 cal ka. The Saint-Narcisse Event is related to the early cold phase of Younger Dryas, as evidenced by other YD ice readvances in Maine, Nova Scotia, and ice cover on the Gaspé Peninsula. It corresponds to a positive change of the budget of the Laurentide Ice Sheet as a result of climate forcing. After a slow ice front retreat during about 900-700 yr, the final phase of YD is marked by the Mars-Batiscan Moraine, located 17 to 70 km north of the Saint-Narcisse Moraine.Le complexe morainique de Saint-Narcisse s’étend sur 750 km le long de la marge méridionale des Laurentides, au Québec, au nord de la vallée du Saint-Laurent, entre l’Outaouais et le Saguenay. Vers l’est, la marge glaciaire était située dans l’estuaire actuel du Saint-Laurent. Vers l’ouest, en Ontario, les formes associées sont suivies dans le massif Algonquin, jusqu’à 235 km de l’Outaouais. Le tracé général du complexe inclut de grands lobes et rentrants liés à la topographie. Dans la basse vallée du Saint-Maurice, la Moraine de Saint-Narcisse est composée de dépôts glaciomarins proximaux, de till et d’argile marine remaniée (Diamicton de Yamachiche) et de till de fusion sur place et de dépôts fluvioglaciaires et juxtaglaciaires (Dépôts de Charette). L’Épisode de Saint-Narcisse est subdivisé en plusieurs phases non nécessairement synchrones sur toute la marge glaciaire: réavancée locale dans les dépressions importantes, phase majeure de stabilisation à l’origine de la Moraine de Saint-Narcisse, fonte sur place indiquée par des structures imbriquées et épandages proglaciaires, puis retra...

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“…Sur leur carte des tendances paléoclimatiques correspondant à cette période, toutes les régions alors déglacées du Canada atlantique sont regroupées sous la rubrique 'progressive warming or stable'. Il faut admettre cependant qu'il y a très peu d'information sur cette période puisque dans l'est canadien les séquences polliniques lacustres postglaciaires ne remontent que très rarement au-delà de 12 000 BP (Anderson et Macpherson, 1994 ;Mott, 1994 ;Richard, 1994 ;Cwynar et al, 1994). Pour pallier cette lacune (au sens géologique du terme), il faut s'en remettre aux carottes océaniques, en particulier celles étudiées par de Vernal et al (1996) autour de TerreNeuve.…”

Section: Discussionunclassified

La déglaciation de la région de Rimouski, Bas-Saint-Laurent (Québec) : indices d’une récurrence glaciaire dans la Mer de Goldthwait entre 12 400 et 12 000 BP

Hétu¹

2002

gpq

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The spatial distribution of land- forms associated with the deglaciation of the Rimouski area (outwash deltas, eskers, kames, and ice disintegration features) was analysed in relation to the morphostructural framework. The main physiographic elements are NE-SW ridges and depressions parallel to the St. Lawrence Valley. To regional scale, the St. Lawrence Valley played a major role in the pattern of deglaciation. The fast penetration of the Goldthwait Sea along the St. Lawrence Valley from the Gulf to Québec City between 14 000 and 12 400 yr BP isolated a regional ice cap on the Appalachian Mountains. After the passage of the calving bay through the study area, slightly before 13 360 yr BP, the Appalachian ice margin stabilized along the first prominant Appalachian ridge (> 140 m) behind the present shore line. This suggest that this ridge helped to anchor the ice cap margin along the southern shore of the Goldth- wait Sea. When ice margin retreated behind the first major Appalachian ridge between 13 360 and 12 700 yr BP, large dead ice bodies were abandonned in the Neigette fault-line valley and in the valleys near Saint- Fabien. Between ca. 12 400 and 12 000 yr BP, the Appalachian ice front stood along the margin of the Sainte-Blandine plateau, only 13 km behind the present shore line. Stratigraphical data indicate that Appalachian ice readvanced into Goldthwait sea during this stage (Older Dryas?). The pattern and chronology of deglaciation beyond the marine limit are still unknown.La distribution des dépôts de marge glaciaire de la région de Rimouski a été analysée en fonction du cadre morphostructural préglaciaire, caractérisé par un relief appalachien typique dont les barres et les sillons, orientés NE-SO, sont subparallèles à la vallée du Saint-Laurent. Cette étude met en lumière l'influence déterminante du contexte morphostructural sur le mode de déglaciation, tant à l'échelle régionale que locale. L'invasion de la Mer de Goldthwait le long du Saint-Laurent, à partir de 14 000 BP, isole progressivement une calotte glaciaire régionale dans les Appalaches. Vers 13 400 BP, la marge septentrionale de la calotte appalachienne suit le tracé de la limite marine, fixée à 140 m d'altitude entre Rimouski et Luceville. Elle s'est stabilisée le long des premières grandes barres appalachiennes qui représentaient la première ligne d'ancrage de la marge glaciaire après l'invasion marine. Durant la phase de retrait qui suit, entre 13 360 et 12 700 ans BP, des masses de glace résiduelles sont abandonnées dans la vallée de ligne de faille de la Neigette et les sillons appalachiens de Saint-Fabien qui s'encombrent de formes de décrépitude (kames et kettles). Entre 12 400 BP et environ 12 000 BP, la marge glaciaire se stabilise sur le rebord du plateau de Sainte-Blandine, à moins de 13 km du littoral actuel. Cette période se signale par une récurrence glaciaire mise en évidence dans trois sites différents. Les modalités et la chronologie de la déglaciation au-delà de la limite marine ne sont pas connues.Man hat die Verteilung...

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Wisconsinan Late‐glacial environmental chage in Québec: A regional synthesis

Cited by 24 publications

References 36 publications

Ecosystem response to Lateglacial and early Holocene climate oscillations in the Great Lakes region of North America

Ecosystem response to Lateglacial and early Holocene climate oscillations in the Great Lakes region of North America

The Saint-Narcisse morainic complex and early Younger Dryas events on the southeastern margin of the Laurentide Ice Sheet

La déglaciation de la région de Rimouski, Bas-Saint-Laurent (Québec) : indices d’une récurrence glaciaire dans la Mer de Goldthwait entre 12 400 et 12 000 BP

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