Holocene Stratigraphy and Geomorphology of Flintstone Hill
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Document generated on 09/25/2021 12:20 p.m. Géographie physique et Quaternaire Holocene Stratigraphy and Geomorphology of Flintstone Hill, Lauder Sandhills, Glacial Lake Hind Basin, Southwestern Manitoba Stratigraphie et géomorphologie holocène de la Flintstone Hill (Lauder Sandhills) dans le bassin du Lac glaciaire Hind, dans le sud-ouest du Manitoba Estratigrafia y geomorfología holocena de la región de Flinstone Hills (Lauder Sandhills) en la cuenca del Lake glaciar Hind en el sudoeste de Manitoba, Canadá Garry L. Running, Karen G. Havholm, Matt Boyd and Dion J. Wiseman Drylands: Holocene Climatic, Geomorphic and Cultural Change on Article abstract the Canadian Prairies Sediments exposed at Flintstone Hill in a Souris River cutbank provide the Volume 56, Number 2-3, 2002 most complete postglacial stratigraphic section in the Glacial Lake Hind Basin (GLHB), southwestern Manitoba. Four lithologic units, A-D, are observed: A1 URI: https://id.erudit.org/iderudit/009112ar (~2 m thick), glaciolacustrine silts and clays that grade upward to peat and DOI: https://doi.org/10.7202/009112ar record final regression of Glacial Lake Hind (~10 500-9300 BP); A2 (~1.5 m thick), low energy fluvial marl and silts grading to O-horizon(s) (by 6700 BP); B (1.5 m thick), dune sands that migrated from the southwest, contrary to the See table of contents modern wind regime (after ~6700 BP); C (1.0 m thick), thin fluvial deposit between eolian sand sheets (~5500-3200 BP); D (up to 7 m thick), parabolic dune on the modern landscape oriented consistent with the modern wind Publisher(s) regime, blowouts suggest episodic dune reactivation (~3200 BP to present). Overall, Flintstone Hill deposits record draining of Glacial Lake Hind, Les Presses de l'Université de Montréal establishment of the Souris River channel through the GLHB, mid-Holocene eolian activity / landscape instability greater than present, and a return to ISSN nearly modern conditions by ~5400 BP. Native inhabitants in the GLHB focused 0705-7199 (print) on exploiting wetlands and wet meadows before 9300 BP and a landscape 1492-143X (digital) similar to the present thereafter. Explore this journal Cite this article Running, G. L., Havholm, K. G., Boyd, M. & Wiseman, D. J. (2002). Holocene Stratigraphy and Geomorphology of Flintstone Hill, Lauder Sandhills, Glacial Lake Hind Basin, Southwestern Manitoba. Géographie physique et Quaternaire, 56(2-3), 291–303. https://doi.org/10.7202/009112ar Tous droits réservés © Les Presses de l'Université de Montréal, 2002 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/ GPQ_56-2-3.qxd 13/05/04 9:58 AM Page 291 Géographie physique et Quaternaire, 2002, vol. 56, nos 2-3, p. 291-303, 3 fig., 2 tabl. HOLOCENE STRATIGRAPHY AND GEOMORPHOLOGY OF FLINTSTONE HILL, LAUDER SANDHILLS, GLACIAL LAKE HIND BASIN, SOUTHWESTERN MANITOBA Garry L. RUNNING IV*, Karen G. HAVHOLM, Matt BOYD and Dion J. WISEMAN, respectively: Department of Geography and Anthropology, University of Wisconsin-Eau Claire, Eau Claire, Wisconsin 54702-4004, U.S.A.; Department of Geology, University of Wisconsin-Eau Claire, Eau Claire, Wisconsin 54702-4004, U.S.A.; Department of Anthropology, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario P7B 5E1; Department of Geography, Brandon University, 270 18th Street, Brandon, Manitoba R7A 6A9. ABSTRACT Sediments exposed at Flintstone RÉSUMÉ Stratigraphie et géomorphologie RESUMEN Estratigrafia y geomorfología Hill in a Souris River cutbank provide the holocène de la Flintstone Hill (Lauder holocena de la región de Flinstone Hills most complete postglacial stratigraphic sec- Sandhills) dans le bassin du Lac glaciaire (Lauder Sandhills) en la cuenca del Lake gla- tion in the Glacial Lake Hind Basin (GLHB), Hind, dans le sud-ouest du Manitoba. Les ciar Hind en el sudoeste de Manitoba, southwestern Manitoba. Four lithologic units, sédiments à découvert de la Flintstone Hill, Canadá. Los sedimentos expuestos en la A-D, are observed: A1 (~2 m thick), glaciola- sur la berge escarpée de la rivière Souris, zona de Flinstone Hills en la ribera del Souris custrine silts and clays that grade upward to offrent la séquence stratigraphique postgla- River proporcionan el registro estratigráfico peat and record final regression of Glacial ciaire la plus complète du bassin du Lac gla- post-glaciar más completo de la cuenca del Lake Hind (~10 500-9300 BP); A2 (~1.5 m ciaire Hind. Quatre unités lithologiques, de Lake Hind, al sudoeste de Manitoba. Se dis- thick), low energy fluvial marl and silts grad- A à D, y sont observées : A1 (~2 m d’épais- tinguen cuatro unidades litológicas: A-D. La ing to O-horizon(s) (by 6700 BP); B (1.5 m seur), silts et argiles glaciolacustres au gra- unidad A1, de unos 2 m de grosor, está com- thick), dune sands that migrated from the noclassement vertical progressif jusqu’à la puesta por limo y arcilla glaciolacustres, que southwest, contrary to the modern wind tourbe témoignent de la dernière régression pasan gradualmente a turba en la parte super- regime (after ~6700 BP); C (1.0 m thick), thin du Lac glaciaire Hind (~10 500-9300 BP) ; A2 ior y evidencian la regresión final del Lake gla- fluvial deposit between eolian sand sheets (~1,5 m d’épaisseur), marnes fluviatiles de ciar Hind hace unos 10 500 a 9300 años; la (~5500-3200 BP); D (up to 7 m thick), para- faible énergie et silts jusqu’à un horizon O unidad A2 de alrededor 1.5 m de grosor, com- bolic dune on the modern landscape oriented (vers 6700 BP); B (1,5 m d’épaisseur), sables puesta de marga de baja intensidad fluvial y consistent with the modern wind regime, dunaires en provenance du sud-ouest, contrai- de limo pasa gradualmente a un horizonte O blowouts suggest episodic dune reactivation rement au régime des vents actuel (après hace unos 6700 años; la unidad B de aproxi- (~3200 BP to present). Overall, Flintstone Hill ~6700 BP) ; C (1,0 m d’épaisseur), dépôt flu- madamente 1.5 m de espesor, compuesta de deposits record draining of Glacial Lake Hind, viatile mince entre des couches de sable dunas que migraron desde sudoeste, en direc- establishment of the Souris River channel (~5500-3200 BP); D (jusqu’à 7m d’épaisseur), ción opuesta a la corriente eólica actual alre- through the GLHB, mid-Holocene eolian dune parabolique faisant partie du paysage dedor de unos 6700 años anteriores al pre- activity / landscape instability greater than moderne et orientée selon le régime des vents sente; la unidad C de 1.0 m de espesor, present, and a return to nearly modern con- actuel, avec des creux de déflation témoignant compuesta por una capa fina de depósitos flu- ditions by ~5400 BP.Native inhabitants in the de réactivations dunaires épisodiques viales alternados con arenas datando de unos GLHB focused on exploiting wetlands and (~3200 BP à aujourd’hui). En résumé, les 5000 a 3200 años anteriores al presente; la wet meadows before 9300 BP and a land- dépôts de la Flintsone Hill attestent d’abord unidad D que abarca mas de 7 m de grosor scape similar to the present thereafter. de la vidange du Lac glaciaire Hind, puis de compuesta por la duna parabólica del paisaje l’établissement du chenal de la rivière Souris actual orientada en la dirección del régimen à travers le bassin, d’une activité éolienne et eólico moderno. Las zonas de excavación eóli- d’une instabilité des paysages à l’Holocène ca sugieren la reactivación de las dunas hace moyen plus grande que maintenant et de l’éta- unos 3200 años. En conjunto, los depósitos blissement de conditions quasi contempo- provenientes de Flinstone Hills evidencian la raines vers 5400 BP. Les premiers habitants canalización del Lake glaciar Hind y el esta- du bassin ont d’abord exploité les terres blecimiento del cauce del Souris River a través humides et les prés humides avant 9300 BP, de la cuenca. Además, a mediados del puis un paysage semblable à celui d’aujour- Holoceno, una actividad eólica y una inesta- d’hui par la suite. bilidad del paisaje mayores a la época actual y el regreso a una condición similar al pre- sente hace unos 5400 años. Hace aproxima- damente 9300 años los habitantes de la cuen- ca del Lake glaciar Hind explotaron las tierras y praderas húmedas, posteriormente lo hicie- ron en un paisaje similar al actual. Manuscrit reçu le 12 novembre 2002 ; manuscrit révisé accepté le 23 juillet 2003 (publié en mai 2004) *E-mail address: [email protected] GPQ_56-2-3.qxd 13/05/04 9:58 AM Page 292 292 G. L. RUNNING IV, K. G. HAVHOLM, M. BOYD and D. J. WISEMAN INTRODUCTION PHYSICAL SETTING It has been widely recognized by archeologists (Epp, 1984, 1986; Meyer and Epp, 1990) that throughout the Holocene GEOLOGY, CLIMATE, VEGETATION human groups used distinct, identifiable locales within the The GLHB is located in southwestern Manitoba, approxi- Canadian prairies with greater frequency than the surrounding mately 80 km southwest of Brandon (Fig. 1). The basin occu- grasslands. As a result of Pleistocene glacial history and more pies a buried bedrock valley, a re-entrant into the Pembina recent geomorphic processes these locales are characterized Escarpment (a northeast-trending bedrock cuesta). This promi- by greater geomorphic complexity and topographic relief than nent escarpment separates the Manitoba Lowland to the east surrounding grasslands.