GEOSCAN, résultats de la recherche


TitreCorrelating high-resolution multibeam sonar backscatter with benthic sediment grain-size distributions to aid numerical modeling in the Mississippi Bight
TéléchargerTéléchargement (publication entière)
AuteurQuas, L; Church, I; O'Brien, S J; Wiggert, J D
SourceProgram and abstracts: 2017 GeoHab Conference, Dartmouth, Nova Scotia, Canada; par Todd, B J; Brown, C J; Lacharité, M; Gazzola, V; McCormack, E; Commission géologique du Canada, Dossier public 8295, 2017 p. 98, (Accès ouvert)
LiensGeoHab 2017
ÉditeurRessources naturelles Canada
Réunion2017 GeoHab: Marine Geological and Biological Habitat Mapping; Dartmouth, NS; CA; mai 1-4, 2017
Documentdossier public
Mediaen ligne; numérique
Référence reliéeCette publication est contenue dans Todd, B J; Brown, C J; Lacharité, M; Gazzola, V; McCormack, E; (2017). Program and abstracts: 2017 GeoHab Conference, Dartmouth, Nova Scotia, Canada, Commission géologique du Canada, Dossier public 8295
Lat/Long OENS -89.5000 -85.0000 30.5000 29.0000
Sujetstechniques de cartographie; océanographie; milieux marins; études côtières; conservation; organismes marins; écologie marine; gestion des ressources; peuplements biologiques; etudes de l'environnement; écosystèmes; sédiments marins; repartition granulométrique; benthos; levés géophysiques; levés acoustiques marins; levés au sonar; sonar latéral; établissement de modèles; bathymétrie; topographie du fond océanique; déversements de pétrole; biogéochimie; transport des sediments; suspension des sédiments; carottes de sédiment marin; analyse granulométriques; biologie; géologie marine; géologie des dépôts meubles/géomorphologie; géologie de l'environnement; géophysique; combustibles fossiles; géochimie
ProgrammeGéoscience en mer, Géoscience de la gestion des océans
Diffusé2017 09 26
Résumé(disponible en anglais seulement)
Multibeam acoustic backscatter intensity data can serve as a proxy for the composition and distribution of surficial seabed sediments, but without calibration and realistic seabed models there can be uncertainty in the analysis. Mosaics of the acoustic response of the seabed normalized to a fixed grazing angle provide an indication of spatial variations in seabed scattering and, therefore, an estimate of general grain-size distributions. These characteristics, along with multibeam bathymetry and sediment ground truth, can be used to inform numerical model development, like the high resolution biogeochemical/lower trophic level synthesis model being developed as part of the Gulf of Mexico Research Initiative's (GoMRI) CONsortium for oil spill exposure pathways in COastal River-Dominated Ecosystems (CONCORDE) project.
One of the necessary model inputs is bottom sediment characterization that influences local sediment transport and resuspension. To obtain this input parameter, a Teledyne Reson SeaBat 7125 SV2 multibeam sonar was operated to collect seafloor acoustic backscatter data. Surficial sediment cores and grain-size analyses were performed at select locations along the CONCORDE observational corridors to constrain the backscatter data, produce acoustically- derived sediment distribution maps, and provide sediment type input parameters for the biogeochemical model. The numerical model simulations are used to assess sediment transport in the river-dominated, coastal environment of the Mississippi Bight region on hourly to daily timescales. The sediment distribution corridor maps developed as part of this project will further our understanding of the benthic and demersal ecosystems within the Mississippi Bight.