| Titre | Reconstructing ice-margin retreat using delta morphostratigraphy |
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| Auteur | Dietrich, P; Ghienne, J F; Normandeau, A ; Lajeunessse, P |
| Source | Scientific Reports vol. 7, 16936, 2017, 10p., https://doi.org/10.1038/s41598-017-16763-x  Accès ouvert |
| Image |  |
| Année | 2017 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20170165 |
| Éditeur | Springer Nature |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1038/s41598-017-16763-x |
| Media | papier; en ligne; numérique |
| Formats | pdf |
| Province | Québec |
| SNRC | 12D; 12C; 12E; 12F; 12L; 12K; 12M; 12N; 22 |
| Région | Côte-Nord; Gulf of St-Lawrence |
| Lat/Long OENS | -73.0000 -60.0000 52.0000 48.0000 |
| Sujets | sédiments deltaïques; faciès deltaïques; dépôt deltaïque; deltas; directions des mouvements de la glace; écoulement glaciaire; retrait de la glace; nappes glaciaires; dépôts fluvioglaciaires; sediments de
contact glaciaire; modèles de sedimentation; dynamique sédimentaire; déplacement des sédiments; sédimentologie; géologie des dépôts meubles/géomorphologie |
| Illustrations | cartes de localisation; diagrammes schématiques; tableaux |
| Diffusé | 2017 12 05 |
| Résumé | (disponible en anglais seulement)
The paleogeographic reconstruction of the successive inland positions of a retreating ice sheet is generally constrained by mapping moraines. However, deltaic
complexes constructed by sedimentcharged meltwater can also provide a record of the retreating ice-margin positions. Here, we examine a serie of ice-contact, ice-distal glaciofluvial and paraglacial depositional systems that developed
along the
Québec North Shore (eastern Canada) in the context of falling relative sea level during the northward retreat of the Laurentide Ice Sheet (LIS). Ice-contact depositional systems formed when the LIS was stillstanding along the Québec North Shore.
Subsequent inland retreat of the ice margin generated glacial meltwaters feeding sediment to glaciofluvial deltas, leading to their rapid progradation. The retreat of the ice margin from drainage basins was marked by the onset of paraglacial
processes such as the shutdown of delta progradation, severe fluvial entrenchment, and deposition of shallow-marine strata. Four end-member scenarios describe the spatial and stratigraphic distribution of these three depositional systems (ice-contact
deposits, ice-distal glaciofluvial deltas, and paraglacial
suites). They reflect both the inherited drainage basin physiography and the retreat pattern of the ice margin. Applied to twenty deltaic complexes, these end-members allowed us to refine
the model of LISmargin retreat over southeastern Québec. |
| Sommaire | (Résumé en langage clair et simple, non publié)
Des systèmes deltaïques établis lorsque les eaux de la fonte des glaciers transportaient de grands volumes de sédiments vers la mer alors que le
niveau de celle-ci baissait rapidement ont laissé des traces des positions antérieures de la marge de l'Inlandsis laurentien. |
| GEOSCAN ID | 305605 |
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