| Titre | Deconstructing the Newmarket Till in south-central Ontario |
| Télécharger | Téléchargement (publication entière) |
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| Licence | Veuillez noter que la Licence du gouvernement
ouvert - Canada remplace toutes les licences antérieures. |
| Auteur | Mulligan, R P M; Bajc, A F; Eyles, C |
| Source | Regional-Scale Groundwater Geoscience in Southern Ontario: An Ontario Geological Survey, Geological Survey of Canada, and Conservation Ontario Geoscientists Open House; par Russell, H A J ; Ford, D; Holysh, S; Priebe, E H; Commission géologique du
Canada, Dossier public 8528, 2019 p. 21, https://doi.org/10.4095/313595  Accès ouvert |
| Année | 2019 |
| Séries alt. | Ontario Geological Survey, Open File Report 6349 |
| Éditeur | Ressources naturelles Canada |
| Éditeur | Gouvernement de l'Ontario |
| Réunion | Regional-Scale Groundwater Geoscience in Southern Ontario: Open House; Guelph; CA; février 27-28, 2019 |
| Document | dossier public |
| Lang. | anglais |
| DOI | https://doi.org/10.4095/313595 |
| Media | en ligne; numérique |
| Référence reliée | Cette publication est contenue dans Regional-Scale Groundwater Geoscience in Southern Ontario: An Ontario Geological Survey, Geological Survey of Canada, and Conservation Ontario Geoscientists Open House |
| Formats | pdf |
| Province | Ontario |
| SNRC | 30; 31B; 31C; 31D; 31E; 31G; 40; 41A; 41G; 41H/03; 41H/04; 41H/05; 41H/06; 41H/12; 41H/13 |
| Région | le sud de l'Ontario |
| Lat/Long OENS | -84.0000 -74.0000 46.0000 41.5000 |
| Sujets | dépôts glaciaires; topographie glaciaire; tills; eau souterraine; régimes des eaux souterraines; distribution des sédiments; trous de mine; échantillons carrotés; stratigraphie du till; modèles; géologie
du substratum rocheux; lithologie; topographie du substratum rocheux; erosion glaciaire; milieu sédimentaire; chenaux d'eau de fonte; analyses hydrauliques; Till de Newmarket ; Calotte glaciaire Laurentide; hydrogéologie; géologie des dépôts
meubles/géomorphologie; sédimentologie; stratigraphie; Phanérozoïque; Cénozoïque; Quaternaire |
| Diffusé | 2019 02 08 |
| Résumé | (disponible en anglais seulement)
The Newmarket Till (NT) records the advance of the Laurentide Ice Sheet over south-central Ontario during the Late Wisconsin. The till occurs across a wide area
of the province, including three prominent physiographic regions. The NT caps and flanks the Niagara Escarpment, a regional scale bedrock scarp 200-300 m high, and occurs across drumlinized sediment-cored uplands underlain by >150 m of pre-Late
Wisconsin sediments as well as beneath intervening lowland plains and tunnel valleys incised into pre-Late Wisconsin sediments and Paleozoic bedrock. Detailed surficial mapping over 3750 km2 in Simcoe County and surrounding areas has identified
consistent internal facies within the uplands, but significant variability, both spatially and vertically, in matrix texture, colour, consolidation, and clast content, fabric and lithology characterizes the NT within the lowlands and in areas along
the Niagara Escarpment. This variability led to previous interpretations of multiple till sheets involving repeated glacier advance and retreat phases during the Late Wisconsin. Combined analysis of internal sedimentology, stratigraphic information
gained from 58 continuously-cored boreholes, and morphological data from recently-released high-resolution terrain models, indicates that the NT sediment package is characterized by a wide variety of distinct diamict units and interbedded stratified
sediments that are linked to changes in substrate lithology and topography. The varying composition of the NT records evolving subglacial erosional and depositional conditions related to fluctuating subglacial stress regimes, porewater pressures and
meltwater drainage. The wide range of properties that characterize the NT has significant implications for understanding and predicting its local hydraulic function as a 'leaky aquitard'.
In the future, the groundwater initiative aims to enhance
integration of its three core activities thereby providing a holistic approach to assessments of the provincial groundwater resource. Continued investigations will allow for the synthesis of information from individual regional studies to
scales. |
| Sommaire | (Résumé en langage clair et simple, non publié)
Volume des résumés pour la Commission géologique de l'Ontario et la commission geologique du Canada géoscience des eaux souterraines de la CGC
portes ouvertes avec conservation Ontario. |
| GEOSCAN ID | 313595 |
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