| Titre | Quaternary stratigraphy and glacial history at Peace River, Alberta |
| |
| Auteur | Paulen, R ;
Beaudoin, A; Ross, M; Botterill, S |
| Source | GAC®-MAC 2021, London, Canada: Exploring Geosciences Through Time and Space/GAC®-MAC 2021, London, Canada : Explorer les géosciences à travers le temps et l'espace; L'Association géologique du
Canada-L'Association minéralogique du Canada, Réunion annuelle conjointe, Recueil des résumés vol. 44, 2021 p. 245  Accès ouvert |
| Liens | Online - En ligne (complete
volume - volume complet, PDF, 2.45 MB)
|
| Image |  |
| Année | 2021 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20210236 |
| Éditeur | Association géologique du Canada |
| Réunion | Geological Association of Canada-Mineralogical Association of Canada Joint Annual Meeting 2021; London, ON; CA; Novembre 1-5, 2021 |
| Document | publication en série |
| Lang. | anglais |
| Media | numérique; en ligne |
| Formats | pdf |
| Province | Alberta |
| SNRC | 84C |
| Région | Rivière de la Paix |
| Lat/Long OENS | -118.0000 -116.0000 57.0000 56.0000 |
| Sujets | antecedents glaciaires; glaciation; Wisconsinien; écoulement glaciaire; transport des sediments; dispersion des sédiments; glissements de terrain; sédimentation; géologie du substratum rocheux;
lithologie; roches sédimentaires; schistes; datation radiométrique; datation au radiocarbone; sediments; dépôts glaciaires; tills; loess; paléosols; fossiles; plantes fossiles; Calotte glaciaire Laurentide; Bouclier Canadien; Formation de Shaftesbury
; directions d'écoulement glaciaire; sédiments fluvioglaciaires; sédiments alluviaux; géologie des dépôts meubles/géomorphologie; stratigraphie; géochronologie; Nature et environnement; Sciences et technologie; Phanérozoïque; Cénozoïque; Quaternaire;
Mésozoïque; Crétacé; Précambrien |
| Programme | GEM-GéoNord : La géocartographie de l'énergie et des minéraux
Zone prioritaire de recherche dans le centre de l'Arctique - Activité 1 de l'Arctique central |
| Diffusé | 2021 11 01 |
| Résumé | (disponible en anglais seulement)
The Quaternary stratigraphy documented in Alberta's Peace River lowlands has been subject to many conflicting interpretations. This is probably due to the lack
of a complete stratigraphic sequence preserved at a single section because of extensive landsliding along the Peace River valley, as well as a lack of chronologic control for lower parts of the sequence. There is ongoing debate over the number and
style of Laurentide glacial advances in the Peace River district of western Alberta and eastern British Columbia. Given its northern Alberta location, resolving the glacial record of this area has important implications for understanding the
evolution of the Laurentide Ice Sheet. The valley-fill sediments located at the confluence of the Heart and Peace rivers, at the town of Peace River, Alberta, provide perhaps the best record in western Canada of a continuum of Quaternary
sedimentation from the preglacial bedrock surface to present. The composite stratigraphy of the Peace River valley (Fig. 1), which is 187 m thick, records the transition from preglacial fluvial sedimentation (unit 1), to a penultimate proglacial
sedimentary sequence (units 2 and 3) conformably overlain by interstadial fluvial sediments (unit 4) of possible MIS-3 age, or older (based on radiocarbon). In turn, these are overlain by a Late Wisconsin ice advance/retreat cycle of sedimentation
from the Laurentide Ice Sheet (units 5-8). The sequence is capped with Holocene cliff-top loess with paleosols, yielding mollusc and plant macrofossils. The only till unit in the stratigraphy (Unit 7) is from the Late Wisconsin glacial advance. The
Canadian Shield lithologies in the lower fluvial sediments are from westward draining catchments, derived from the Buffalo Head Hills, where multiple, older glacial sediments have been documented. Consequently, there is evidence for only a single
Laurentide glaciation in the eastern Peace River district, similar to what is defined to the southwest in other exposures on the Smoky River. Figure 1. Composite stratigraphy at the confluence of the Heart and Peace rivers. The Quaternary sediments
overlie Early Cretaceous (Albian) Shaftesbury Formation shale, and consist of nine major units, approximately 187 m thick. |
| Sommaire | (Résumé en langage clair et simple, non publié)
Résumé de la stratigraphie des événements glaciaires pour le secteur nord-ouest de la Calotte glaciaire laurentide, dans l'une des plus grandes
vallées préglaciaires du nord-ouest du Canada. Les unités sédimentaires qui y sont exposées ont rarement été documentées dans leur intégralité. Ceci est important pour contraindre les anciens modèles de calotte glaciaire. |
| GEOSCAN ID | 328876 |
|
|