GEOSCAN, résultats de la recherche


TitreThe shallow geology of a portion of Laurentian Channel east of Cape Breton Island, offshore Nova Scotia and Newfoundland and Labrador
AuteurKing, E L
SourceCommission géologique du Canada, Dossier public 6731, 2014, 26 pages, (Accès ouvert)
ÉditeurRessources naturelles Canada
Documentdossier public
Medianumérique; en ligne
ProvinceRégion extracotière de l'est
Lat/Long OENS-59.6667 -56.5000 47.1667 46.1667
Sujetselements glaciaires; dépôts glaciaires; topographie glaciaire; topographie du fond océanique; topographie du fond océanique; levés géophysiques; bathymétrie; boues; sables; tills; blocs; caractéristiques sous-marines; géologie des dépôts meubles/géomorphologie; géologie marine; géologie de l'ingénieur; Cénozoïque; Quaternaire
Illustrationslocation maps; cross-sections; tables; profiles
ProgrammeGéoscience en mer, La géoscience pour les développements extracôtiers de la côte est
Diffusé2014 06 03
Résumé(Sommaire disponible en anglais seulement)
Current hydrocarbon and environmental interests in part of the central Laurentian Channel, south of Burgeo Bank, demands a review of the current understanding of the area's shallow geological conditions. Multi-layered map themes, both new and old, show the distribution and attributes of the bedrock and overburden. Broadly folded and faulted Carboniferous siliciclastics and evaporites of the Sydney Basin floor the entire area. The bedrock surface is glacially smoothed and overlain by a simple stratigraphic series of one or two tills, up to 60 m thick, followed by glacimarine deposits, up to 30 m thick. Both are turbated by relict iceberg scours. At the seafloor muds are common below about 250 m water depth and patchy sand and gravel shallower than about 80 m, while till and glacial sediments underlie most of the area, yet crop out over large areas. Physical properties indicate competent tills with strengths of 150 kPa, much softer overlying glacimarine muds (ca. 10-20 kPa) and very thin covering muds (<10 kPa). GSC-A data holdings include no biological observations; other areas of the Channel with muddy seafloor support moderate sponge and sea pen populations with anemones and greater diversity on harder (generally glacial) substrate. Geo-features of potential interest to engineering application include shallow gas and pockmarks, rare buried channels and submarine sediment mass failure (old), heavily relict icebergscoured terrain and both hard and soft sediments. Neo-tectonic activity level around salt diapirs and faults are inconclusive in terms of magnitude and timing.