GEOSCAN, résultats de la recherche


TitreOn the spatial frequency of linear ice scours on the seabed
AuteurGaskill, H; Lewis, C F M
SourceCold Regions Science and Technology vol. 15, no. 2, 1988 p. 107-130,
Séries alt.Commission géologique du Canada, Contributions aux publications extérieures 20987
ÉditeurElsevier BV
Documentpublication en série
Mediapapier; en ligne; numérique
ProvinceRégion extracotière de l'est; Région extracotière du nord
SNRC107C; 14C; 13N; 13O; 1 /NE
Sujetsérosions par la glace; méthodes statistiques; icebergs; levés géophysiques; sonar latéral; établissement de modèles; pipelines; géologie marine; géomathématique; géophysique; Quaternaire
Illustrationssonograms; formulae
Résumé(disponible en anglais seulement)
In this paper the factors which affect the spatial frequency of linear scours on the seabed are identified through the use of a Monte Carlo simulation model. This identification is followed by analysis leading to various formulas useful for assessing the risk to undesea structures from scouring ice. Specifically, formulas for the conditional probability that a scour will intersect a segment of pipeline or an installation in the shape of a convex geometric figure, expressed in terms of measured scour parameters, are developed. In addition, formulas for the annual probability that a segment of pipeline may be scoured and the expected number of pipeline/scour interactions are obtained. Similarly, it is shown how to calculate the annual probability that a rectangular region will be scoured. Definitions of areal and scour start-point density are presented which precisely delineate the important concepts associated with scour frequency as seen in existing sonogram imagery. The use of these concepts is illustrated by their application to some simulated sonogram imagery. Finally, the methods are applied to recent resurvey results for an area on the northern Grand Banks of Newfoundland to estimate an upper bound on the annual scour rate for the region.