Shore platform downwearing in eastern Canada; A 9–14 year micro-erosion meter record

Geomorphology ◽  
2018 ◽  
Vol 311 ◽  
pp. 90-102 ◽  
Author(s):  
Alan S. Trenhaile ◽  
Neil J. Porter
2007 ◽  
Vol 60 (1) ◽  
pp. 19-30 ◽  
Author(s):  
Alan S. Trenhaile ◽  
Neil J. Porter ◽  
Jacob I. Kanyaya

Abstract This research is conducted on a mesotidal, argillite shore platform at Mont Louis in Gaspé, Québec, and on macrotidal platforms in the basalts of Scots Bay and the sandstones of Burncoat Head in Nova Scotia. Rock samples have been subjected to wetting and drying and to salt weathering cycles. The platforms were surveyed; rock hardness was determined with a Rock Test Hammer; waves were recorded in the field; and downwearing rates were measured at 56 micro-erosion meter stations over 1 to 3 years. Weathering is the dominant process at Mont Louis, although the horizontal platform may have been cut by waves at the high tidal level. Wave backwearing was much more important than downwearing by weathering during the Holocene at Scots Bay. Wave quarrying only occurs on a few scarps today, however, and without much abrasive material, slow downwearing now dominates over most of the platform surface. Waves probably help to remove loosened sand grains at Burncoat Head, thereby contributing to platform downwearing. Abrasion is also important in places, but the data suggest that backwearing by wave quarrying and probably frost has been a little more important than downwearing by abrasion and weathering during the Holocene.


Geomorphology ◽  
2010 ◽  
Vol 118 (1-2) ◽  
pp. 1-12 ◽  
Author(s):  
Neil J. Porter ◽  
Alan S. Trenhaile ◽  
Kyle J. Prestanski ◽  
Jacob I. Kanyaya

Geomorphology ◽  
2010 ◽  
Vol 116 (1-2) ◽  
pp. 77-86 ◽  
Author(s):  
Neil J. Porter ◽  
Alan S. Trenhaile ◽  
Kyle J. Prestanski ◽  
Jacob I. Kanyaya

2020 ◽  
Vol 643 ◽  
pp. 197-217 ◽  
Author(s):  
SME Fortune ◽  
SH Ferguson ◽  
AW Trites ◽  
B LeBlanc ◽  
V LeMay ◽  
...  

Climate change may affect the foraging success of bowhead whales Balaena mysticetus by altering the diversity and abundance of zooplankton species available as food. However, assessing climate-induced impacts first requires documenting feeding conditions under current environmental conditions. We collected seasonal movement and dive-behaviour data from 25 Eastern Canada-West Greenland bowheads instrumented with time-depth telemetry tags and used state-space models to examine whale movements and dive behaviours. Zooplankton samples were also collected in Cumberland Sound (CS) to determine species composition and biomass. We found that CS was used seasonally by 14 of the 25 tagged whales. Area-restricted movement was the dominant behaviour in CS, suggesting that the tagged whales allocated considerable time to feeding. Prey sampling data suggested that bowheads were exploiting energy-rich Arctic copepods such as Calanus glacialis and C. hyperboreus during summer. Dive behaviour changed seasonally in CS. Most notably, probable feeding dives were substantially shallower during spring and summer compared to fall and winter. These seasonal changes in dive depths likely reflect changes in the vertical distribution of calanoid copepods, which are known to suspend development and overwinter at depth during fall and winter when availability of their phytoplankton prey is presumed to be lower. Overall, CS appears to be an important year-round foraging habitat for bowheads, but is particularly important during the late summer and fall. Whether CS will remain a reliable feeding area for bowhead whales under climate change is not yet known.


2003 ◽  
Vol 3 (5-6) ◽  
pp. 15-22
Author(s):  
P. Kouadio ◽  
M. Tétrault

Three colored surface water nanofiltration pilot-scale projects were conducted in the province of Quebec (eastern Canada), between November 2000 and March 2002, by the company H2O Innovation (2000) inc., for the municipalities of Lac Bouchette, Latulipe-et-Gaboury and Charlesbourg (now part of Quebec City). Results indicated that nanofiltration permeate quality has an advance on present drinking water regulation standard in Quebec, but important membrane fouling occurred. Fouling can be controlled by pretreatment and optimization of the operating conditions.


2017 ◽  
Author(s):  
Alba M. Rodriguez Padilla ◽  
◽  
John Onwuemeka ◽  
John Onwuemeka ◽  
Yajing Liu ◽  
...  

2020 ◽  
Vol 110 (2) ◽  
pp. 471-488 ◽  
Author(s):  
Samantha M. Palmer ◽  
Gail M. Atkinson

ABSTRACT Spectral decay of ground-motion amplitudes at high frequencies is primarily influenced by two parameters: site-related kappa (κ0) and regional Q (quality factor, inversely proportional to anelastic attenuation). We examine kappa and apparent Q-values (Qa) for M≥3.5 earthquakes recorded at seismograph stations on rock sites in eastern and western Canada. Our database contains 20 earthquakes recorded on nine stations in eastern Canada and 404 earthquakes recorded on eight stations in western Canada, resulting in 105 and 865 Fourier amplitude spectra, respectively. We apply two different methods: (1) a modified version of the classical S-wave acceleration method; and (2) a new stacking method that is consistent with the use of kappa in ground-motion modeling. The results are robust with respect to the method used and also with respect to the frequency band selected, which ranges from 9 to 38 Hz depending on the region, event, and method. Kappa values obtained from the classical method are consistent with those of the stacked method, but the stacked method provides a lower uncertainty. A general observation is that kappa is usually larger, and apparent Q is smaller, for the horizontal component in comparison to the vertical component. We determine an average regional κ0=7  ms (horizontal) and 0 ms (vertical) for rock sites in eastern Canada; we obtain κ0=19  ms (horizontal) and 14 ms (vertical) for rock sites in western Canada. We note that kappa measurements are quite sensitive to details of data selection criteria and methodology, and may be significantly influenced by site effects, resulting in large site-to-site variability.


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