Improvement of Visibility and Severe Sea State Forecasting on the Grand Banks of Newfoundland and Labrador

2016 ◽  
Author(s):  
Terry Bullock ◽  
George A. Isaac ◽  
Jennifer Beale ◽  
Tristan Hauser
Keyword(s):  
Newfoundland And Labrador ◽  
Sea State ◽  
Grand Banks

Assessment of Current Offshore Supply Vessel Capabilities for Crew Transfer Operations in the Flemish Pass

2018 ◽  
Author(s):  
Mitchell Anderson ◽  
David Molyneux
Keyword(s):  
Wave Height ◽  
Newfoundland And Labrador ◽  
Loading Condition ◽  
Oil And Gas ◽  
Time History ◽  
General Purpose ◽  
Ship Motions ◽  
Sea State ◽  
North East ◽  
Increased Risk

The Flemish Pass is a region off the coast of the province of Newfoundland and Labrador in which large oil discoveries have been made in recent years, making it a promising site for future offshore oil and gas developments. The site is located approximately 200 kilometers North-East of the currently producing Jeanne D’Arc Basin. This results in some additional challenges, including: higher waves and rougher seas on average, longer transit time from shore to any potential production facilities, and an increased risk of sea ice. Crew transfers from Offshore Supply Vessels (OSVs) to current production platforms offshore Newfoundland and Labrador are typically accomplished with a FROG-6 personnel-transfer capsule lifted by a platform-board crane. In current practice, for fixed platforms, this is only done when there is a Significant Wave Height (Hs) of 4.0 m or less, regardless of the OSV being used. In the winter months, this general-purpose approach does not allow for an acceptably high operational fraction of time in which crew transfers could be completed in the Flemish Pass. The FROG-6 capsule has designated operational limits based on the relative velocity between the capsule and the vessel deck, which will vary based on ship size, loading condition, and sea-state. Considering this, a series of geometrically similar OSV hull forms are created to represent the range of currently operating vessels. The developed models are between 70.0–90.0 m long, have a maximum breadth between 17.0–22.0 m, and block coefficients ranging from 0.65–0.79. Using ShipMo3D, a potential flow / panel code seakeeping solver, a 20 minute time history of ship motions is determined for all the modelled OSVs, across the range of sea-states realistically expected in the Flemish Pass. Then, a MATLAB script is used to transform these motions into deck velocities. From these results, the operational limits for crew transfer can be re-defined as a function of ship size, loading condition, and sea-state. This results in higher operability percentages than those achieved from using the flat wave height limit alone, with relatively large variations between differently sized and loaded ships. Further work must be done to officially implement new limits, such as: analysis of additional wave period and height combinations, further analysis of the time between limit exceedances, computational fluid dynamics simulations, “smart crane” modelling, and/or full scale sea trials.

Paleocontinental slopes of East Coast Geosyncline (Canadian Atlantic margin)

1977 ◽  
Vol 14 (11) ◽  
pp. 2553-2564 ◽  
Author(s):  
Lewis H. King ◽  
Ian F. Young
Keyword(s):  
Newfoundland And Labrador ◽  
East Coast ◽  
Shelf Edge ◽  
Mass Wasting ◽  
Scotian Shelf ◽  
Grand Banks ◽  
Shelf Slope ◽  
Seismic Reflection Profiles ◽  
Atlantic Margin ◽  
Upper Slope

A study of processed seismic reflection profiles along the eastern Canadian continental margin indicates the occurrence at depth of paleocontinental slopes of Cenozoic–Mesozoic age, generally in the vicinity of the present continental slope. The paleoslopes are of two general types, constructional and destructional, formed respectively by progradational processes and mass wasting. The inclined beds of the progradational sequence (clinoform beds) represent the constructional slopes and were probably formed at times when deposition was simultaneous on the shelf, slope, and rise. Conditions leading to the establishment of a relatively deep shelf edge would favor constructional slope formation and preservation. A relatively shallow shelf edge, common during times of low sea level, would promote cutback at the shelf edge and upper slope and lead to the formation of destructional slopes. The depth of the shelf edge is mainly established by the balance between rates of sedimentation and subsidence in conjunction with the processes arising from variations in sea level.The sequence of constructional and destructional paleocontinental slopes varies widely along the Canadian Atlantic margin. On the western Scotian Shelf adjacent to the LaHave Platform the paleoslopes are mainly destructional and are in proximity, with only fragmental expression of former constructional slopes remaining. On the eastern Scotian Shelf and Grand Banks destructional paleoslopes are widely spaced in section between thick areas of constructional slope development. Paleoslopes along the northeast Newfoundland and Labrador Shelves are mainly constructional. The differences may be related to age of opening of the Atlantic Basin.The type and distribution of paleocontinental slopes along a margin could influence the migration of hydrocarbons from the eugeocline to the miogeocline.

Freshwater leech (Annelida: Hirudinida) distribution in the Canadian Province of Newfoundland and Labrador and adjacent regions: check-list, new records, new pigmentation forms, and Pleistocene refugia

Zootaxa ◽  
2007 ◽  
Vol 1657 (1) ◽  
pp. 1-21 ◽  
Author(s):  
JACQUELINE MADILL ◽  
PETER HOVINGH
Keyword(s):  
United States ◽  
Natural History ◽  
Newfoundland And Labrador ◽  
New Records ◽  
The United States ◽  
The Other ◽  
National Museum ◽  
Check List ◽  
Canadian Province ◽  
Grand Banks

The freshwater leeches (Hirudinida) in the Province of Newfoundland and Labrador were investigated by examining theliterature, the Canadian Museum of Nature and the United States National Museum of Natural History records, and aleech survey. New pigmentation forms are described for Erpobdella punctata (Leidy) and Erpobdella obscura (Verrill).This is the first published record for Haemopis lateromaculata Mathers in Canada. Four species (Glossiphonia elegans(Verrill), Helobdella modesta (Verrill), Erpobdella punctata, and Erpobdella obscura) were found in both Labrador andNewfoundland with Erpobdella obscura common in Labrador and the other three species common in Newfoundland.Seven other species of leeches were less abundant in Newfoundland with 6 of these species very restricted in distribution.The abundance of leech species in Newfoundland and the paucity of leech species in Labrador suggested that theisland species were present in a Pleistocene refugium associated with Newfoundland or the Grand Banks. Post-Pleistocenebarriers to leech mobility are examined, and possible timing of colonization events is proposed in this model.

scholarly journals Bottom-up limits to Newfoundland capelin (Mallotus villosus) rebuilding: the euphausiid hypothesis

2013 ◽  
Vol 71 (4) ◽  
pp. 775-783 ◽  
Author(s):  
Shannon G. Obradovich ◽  
Erin H. Carruthers ◽  
George A. Rose
Keyword(s):  
Newfoundland And Labrador ◽  
Gadus Morhua ◽  
Atlantic Cod ◽  
Mallotus Villosus ◽  
Bottom Up ◽  
Grand Banks ◽  
Capelin Mallotus Villosus ◽  
Dietary Component ◽  
Δ 15N ◽  
Δ15n And Δ13c

Abstract Capelin (Mallotus villosus) is the key forage fish species in the Newfoundland and Labrador Shelf ecosystem. Capelin stocks collapsed in the early 1990s, concurrent with declines in “northern” Atlantic cod, Gadus morhua. Neither has fully recovered yet. Changes in growth, condition, and behaviour accompanied capelin declines on the northern Grand Banks (NGB), and remain two decades later. Feeding, growth, and condition of NGB capelin were all lower when compared with capelin from the eastern Scotian Shelf (ESS), where abundance increased following predator declines. For age 2–5 capelin of both sexes, all but one of five comparable age–sex groups were significantly larger on the ESS (e.g. age 3 females average 169 mm on the ESS and 151 mm on the NGB). Neither temperature nor density-dependence explain these differences. However, dietary differences were prominent. ESS capelin had higher total fullness indices (TFIs) than NGB fish at all sizes [mean TFIESS = 1.43 (± 1.14), mean TFINGB = 0.48 (± 0.70)]. Euphausiids (especially Thysanoessa spp.) were a main dietary component on the ESS but not on the NGB. Stable isotope analyses (δ15N and δ13C) for NGB capelin also indicated few dietary euphausiids. Trophic fractionation of δ 15N was 4.740/00, suggesting NGB capelin were food limited. Capelin recovery on the Newfoundland and Labrador Shelf appears limited by bottom-up forcing, in particular lack of euphausiid prey.

Calculation of magnetic flow noise inside an enclosure in a sea-state

1998 ◽  
Author(s):  
Mark Hyman ◽  
Iskender Sahin ◽  
Thai Nguyen
Keyword(s):  
Sea State ◽  
Magnetic Flow ◽  
Flow Noise
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