| Titre | Regional stratigraphic understanding of the Labrador-Baffin Seaway |
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| Auteur | Dafoe, L T ;
Williams, G L; Dickie, K; Gregersen, U; Knutz, P C; Dam, G; Pedersen, G K; Nohr-Hansen, H; Haggart, J W; DesRoches, K |
| Source | GSA 2020 Connects Online; Geological Society of America, Abstracts With Programs vol. 52, no. 6, 200-5, 2020 p. 1, https://doi.org/10.1130/abs/2020AM-355218 |
| Année | 2020 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20200616 |
| Éditeur | Geological Society of America |
| Réunion | GSA 2020 Connects Online - Geological Society of America Annual Meeting; Octobre 26-30, 2020 |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1130/abs/2020AM-355218 |
| Media | numérique; en ligne |
| Formats | html; pdf |
| Province | Terre-Neuve-et-Labrador; Région extracotière de l'est |
| Sujets | Crétacé inférieur; analyses stratigraphiques; interprétations géophysiques; lithologie; paléoenvironnement; discordances; Bassin de Baffin Bay ; géologie de l'environnement; géologie générale;
géochronologie; géophysique; géologie marine; Nature et environnement; stratigraphie; tectonique; Crétacé; Cénozoïque |
| Programme | GEM2 : La géocartographie de l'énergie et des minéraux Région de Baffin |
| Diffusé | 2020 10 29 |
| Résumé | (disponible en anglais seulement)
The Labrador-Baffin Seaway which includes the Labrador Sea, Davis Strait, and Baffin Bay began forming during Early Cretaceous rifting between the paleo-North
American and Greenland plates. Regional geophysical and stratigraphic studies of the resultant offshore and associated onshore basins have been undertaken for decades, but our understanding of the tectonostratigraphic evolution and relationship of
the two margins of the seaway is somewhat uncertain. To resolve this, we integrated interpretations from the conjugate margins and divided the stratigraphy into Cretaceous, lower Cenozoic, and upper Cenozoic intervals, with relationships illustrated
in conjugate margin profiles and distribution maps. We correlated the lithology, ages, paleoenvironments, and unconformities and integrated seismic stratigraphic frameworks from each margin. During the Early Cretaceous, localized basins formed and
were infilled with nonmarine and shallow marine strata, succeeded by a transgressive, Upper Cretaceous marine mudstone and localized sandstone succession as rifting continued and widespread subsidence ensued. Seafloor spreading began in the central
Labrador Sea in the Maastrichtian, but propagated regionally by the Early Paleocene along with significant volcanism centered in the Davis Strait. At about the same time, regional regression took place, with a localized middle Paleocene unconformity
developed along the western margin of the seaway, but significant missing section to the east. The overlying lower Cenozoic interval is middle Paleocene to Middle Miocene and includes a period of basin inversion starting in the late Paleocene, due to
strike-slip motion related to a regional change in the seafloor spreading direction. Initial shallow marine and nonmarine strata are succeeded by a Lower Eocene transgressive phase. Spreading finally ceased in the Late Eocene, but the top of the
lower Cenozoic interval is marked by missing section at the base of major clinothems developed within the upper Cenozoic interval. Progradation during this latest interval built parts of the shelf and blanketed the deep water. Our regional
correlations help to construct a more complete understanding of the tectonostratigraphic evolution of the region, as well as highlight margin-specific and localized events. |
| Sommaire | (Résumé en langage clair et simple, non publié)
Ce travail décrit le cadre stratigraphique intégré de la région de la mer du Labrador, du détroit de Davis et de la baie de Baffin lequel est
lié à l'ouverture de l'océan et des bassins sédimentaires connexes. Les bassins ont été surtout comblés par des roches sédimentaires aussi vieilles que le Crétacé inférieur, les roches les plus jeunes remontant au Cénozoïque et couvrant une grande
partie du fond marin. Nous avons intégré le cadre stratigraphique et sismique des bassins marins au large et ceux détectés sur la terre ferme pour obtenir des comparaisons régionales et une meilleure compréhension de l'histoire
tectonostratigraphique. Nous montrons des sections sismiques et des cartes de répartition pour illustrer ces relations. |
| GEOSCAN ID | 327880 |
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