The stratigraphic imprint of a mid-Telychian (Llandovery, Early Silurian) glaciation on far-field shallow-water carbonates, Anticosti Island, Eastern Canada; pp. 207–213

Understanding the propagation of landslide-generated water waves is of great help against tsunami hazards. In order to investigate the effects of landslide shapes on the far-field leading wave generated by a submerged landslide at a constant depth, three linear wave models with different degrees of dispersive properties are employed in this study. The linear fully dispersive model is then validated by comparing the results against the experimental data available for landslides with a low Froude number. Three simplified shapes of landslides with the same volume, which are unnatural for a body of incoherent material, are used to investigate the effects of landslide shapes on the far-field properties of the generated leading wave over a flat seabed. The results show that the far-field leading crest over a constant depth is independent of the exact landslide shape and is invalid at a shallow water depth. Therefore, the most popular non-dispersive model (also called the shallow water wave model) cannot be used to reproduce the phenomenon. The weakly dispersive wave model can predict this phenomenon well. If only the leading wave is considered, this model is accurate up to at least μ = h0/Lc = 0.6, where h0 is the water depth and Lc denotes the characteristic length of the landslide.

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A large arthropod trackway from the Gaspé Sandstone Group (Middle Devonian) of eastern Canada

Canadian Journal of Earth Sciences ◽

10.1139/e98-057 ◽

1998 ◽

Vol 35 (10) ◽

pp. 1116-1122 ◽

Cited By ~ 14

Author(s):

Simon J Braddy ◽

Andrew RC Milner

Keyword(s):

Shallow Water ◽

Middle Devonian ◽

Eastern Canada

A large arthropod trackway from the Cap-aux-Os Member of the Battery Point Formation (Gaspé Sandstone Group, Middle Devonian), from the Baie de Gaspé, eastern Canada, is described and assigned to the ichnotaxon Palmichnium (= Paleohelcura) antarcticum (Gevers et al., 1971). A large stylonurid eurypterid or scorpion is considered the most likely producer. A shallow-water marginal fluvial environment is inferred as the setting, the animal making a transition from walking to swimming along the course of the trackway.

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Foraminiferal Distribution in the Central and Western Parts of the Late Pleistocene Champlain Sea Basin, Eastern Canada

Géographie physique et Quaternaire ◽

10.7202/032750ar ◽

2007 ◽

Vol 43 (1) ◽

pp. 3-26 ◽

Cited By ~ 13

Author(s):

Jean-Pierre Guilbault

Keyword(s):

Shallow Water ◽

Deep Water ◽

Bottom Water ◽

Late Glacial ◽

Clay Layer ◽

Eastern Canada ◽

Deep Waters ◽

High Zone ◽

Water Stratification ◽

Late Wisconsinan

ABSTRACT Marine sediments from the late-glacial Champlain Sea have been sampled at 20 localities representing the deeper part of the basin, between Ottawa and the Rivière St-François, Québec. Foraminiferal assemblages have been extracted and a sequence of three deep water and two shallow water ecozones recognized. The lowermost zone (A) is characterized by Cassidulina reniforme, Islandiella helenae and I. norcrossi and represents a paleosalinity of 25 to 30%o. The overlying zone B is dominated by Elphidium excavatum. It represents salinities decreasing from 25 to as low as 10%o. The uppermost zone (C) contains only a sparse assemblage of a morphotype of E. excavatum. If suggests a paleosalinity of no more than 10%o. A mostly unfossiliferous silt and clay layer of variable thickness (post-C) occurs above zone C. It is probably lacustrine. Below zone A and above the Late Wisconsinan till there is a pre-A interval whose variable assemblages represent hyposaline environments east of Montréal, predominantly lacustrine conditions west of Montréal and alternating hyposaline/ lacustrine environments near and south of Montréal. Bottom water temperatures were probably "Arctic" (within a few degrees of 0°) from the pre-A interval up to zone B inclusively. The data from zone C are too poor to estimate temperatures. The shallow water zones indicate environments with high (zone EH) or low (zone EA) salinities but of shallower depths than the deep water zones. The existence of two sequences is interpreted as the result of (probably seasonal) water stratification. The data does not allow to determine the depth of the limit between the shallow and deep waters.

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Habitat selection by common eiders in winter and its interaction with flock size

Canadian Journal of Zoology ◽

10.1139/z93-172 ◽

1993 ◽

Vol 71 (6) ◽

pp. 1259-1266 ◽

Cited By ~ 56

Author(s):

Magella Guillemette ◽

John H. Himmelman ◽

Cyrille Barette ◽

Austin Reed

Keyword(s):

Habitat Selection ◽

Shallow Water ◽

Prey Density ◽

Sea Urchins ◽

Day Length ◽

Antipredator Behaviour ◽

Somateria Mollissima ◽

Flock Size ◽

Eastern Canada ◽

Diving Depth

We studied habitat selection in relation to prey density and water depth in the common eider, Somateria mollissima L., wintering in the Gulf of St. Lawrence, eastern Canada. In this region, eiders are confronted with low temperatures, ice cover, and reduced day length. We predicted that they should select feeding habitats characterized by high prey density and shallow water to minimize the time and energy spent while diving. About 1000 flocks were localized by triangulation on our study site (20.5 km2). We inferred the diving depth and the habitat being used from the position of eiders on bathymetric and community maps. The highest density of prey occurred in shallow water reefs where there were patches of blue mussels, Mytilus edulis L., and green sea urchins, Strongylocentrotus droebachienensis (Müller). Despite the fact that eiders can dive to depths as great as 42 m to feed, they strongly aggregate in shallow water, and their distribution closely coincides with the highest density of prey. The degree of selection for the reef habitat varies with seasonal variations in the size of flocks and in the total number of eiders present. Although flocking as an antipredator behaviour cannot be rejected, we interpret the high degree of flocking by eiders in our study area as a strategy to facilitate feeding in winter.

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