The West Greenland Shelf--A Reemerging Basin with Both Shallow and Deep Water Potential

Abstract The West Greenland Atlantic Salmon (Salmo salar) fishery represents the largest remaining mixed-stock fishery for Atlantic Salmon in the Northwest Atlantic and targets multi-sea-winter (MSW) salmon from throughout North America and Europe. We evaluated stock composition of salmon harvested in the waters off West Greenland (n = 5684 individuals) using genetic mixture analysis and individual assignment to inform conservation of North American populations, many of which are failing to meet management targets. Regional contributions to this fishery were estimated using 2169 individuals sampled throughout the fishery between 2011 and 2014. Of these, 22% were identified as European in origin. Major North American contributions were detected from Labrador (∼20%), the Southern Gulf/Cape Breton (29%), and the Gaspe Peninsula (29%). Minor contributions (∼5%) were detected from Newfoundland, Ungava, and Quebec regions. Region-specific catches were extrapolated using estimates of composition and fishery catch logs and harvests ranged from 300 to 600 and 2000 to 3000 individuals for minor and major constituents, respectively. To evaluate the temporal stability of the observed fishery composition, we extended the temporal coverage through the inclusion of previously published data (1995–2006, n = 3095) and data from archived scales (1968–1998, n = 420). Examination of the complete time-series (47 years) suggests relative stability in stock proportions since the late 1980s. Genetic estimates of stock composition were significantly associated with model-based estimates of returning MSW salmon (individual years r = 0.69, and overall mean r = 0.96). This work demonstrates that the analysis of both contemporary and archived samples in a mixed-stock context can disentangle levels of regional exploitation and directly inform assessment and conservation of Atlantic Salmon in the West Greenland interceptory Atlantic Salmon fishery.

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Topographic and Glaciological Controls on Holocene Ice-Sheet Margin Dynamics. Central West Greenland

Annals of Glaciology ◽

10.3189/s0260305500008806 ◽

1990 ◽

Vol 14 ◽

pp. 307-310 ◽

Cited By ~ 11

Author(s):

C.R. Warren ◽

N.R.J. Hulton

Keyword(s):

Ice Sheet ◽

Greenland Ice Sheet ◽

Glacial Maximum ◽

Warm Climate ◽

Short Term ◽

The West ◽

West Greenland ◽

The Past

The retreat of the West Greenland ice sheet from its Sisimiut (Wisconsinan) glacial maximum, was punctuated by a series of Stillstands or small readvances that formed numerous moraines. These landforms have been interpreted in the past as the result of short-term, regional falls in ablation-season temperatures. However, mapping of the geomorphological evidence south of Ilulissat (Jakobshavn) suggests that retreat behaviour was not primarily governed by climate, and therefore that the former ice margins are not palaeoclimatically significant. During warm climate ice-sheet wastage, the successive quasi-stable positions adopted by the ice margin were largely governed by topography. The retreat of the inherently unstable calving glaciers was arrested only at topographically-determined locations where stability could be achieved.

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14C in the Deep Water of the East Atlantic

Radiocarbon ◽

10.1017/s0033822200007505 ◽

1986 ◽

Vol 28 (2A) ◽

pp. 391-396 ◽

Cited By ~ 2

Author(s):

Reiner Schlitzer

Keyword(s):

Deep Water ◽

Large Scale ◽

Bottom Water ◽

Source Parameters ◽

Potential Temperature ◽

Source Terms ◽

East Atlantic ◽

The West ◽

Model Calculations ◽

Inflowing Water

The renewal of east Atlantic deep water and its large-scale circulation and mixing have been studied in observed distributions of temperature, silicate, ΣCO2, and 14C. 14C variations in northeast Atlantic deep water below 3500m depth are small. Δ14C values range from − 100‰ to −125‰. 14C bottom water concentrations decrease from Δ14C =−117‰ in the Sierra Leone Basin to Δ14C = − 123‰ in the Iberian Basin and are consistent with a mean northward bottom water flow. The characteristic of the water that flows from the west Atlantic through the Romanche Trench into the east Atlantic was determined by inspection of θ/Δ14C and θ/SiO2 diagrams. A mean potential temperature of θ = 1.50 ± .05°C was found for the inflowing water. A multi-box model including circulation, mixing, and chemical source terms in the deep water has been formulated. Linear programing and least-squares techniques have been used to obtain the transport and source parameters of the model from the observed tracer fields. Model calculations reveal an inflow through the Romanche Trench from the west Atlantic, which predominates over any other inflow, of (5 ± 2) Sv (potential temperature 1.50°C), a convective turnover of (150 ± 50) years and a vertical apparent diffusivity of (4 ± 1) cm2/s. Chemical source terms are in the expected ranges.

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Developing an Environmental Oil Spill Sensitivity Atlas for the West Greenland Coastal Zone

GIS for Coastal Zone Management ◽

10.1201/9781420023428-26 ◽

2004 ◽

pp. 299-310

Keyword(s):

Coastal Zone ◽

Oil Spill ◽

The West ◽

West Greenland

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Quaternary deposits between the Sukkertoppen ice cap and Nordre Strømfjord

Rapport Grønlands Geologiske Undersøgelse ◽

10.34194/rapggu.v28.7227 ◽

1970 ◽

Vol 28 ◽

pp. 23-25

Author(s):

A Weidick ◽

N.W Ten Brink

Keyword(s):

Land Area ◽

The West ◽

Quaternary Deposits ◽

Sea Levels ◽

West Greenland ◽

Marine Deposits ◽

Ice Cap

The area investigated during 1969 is located approximate1y between 66° 10' and 67° 30' N, and 50° and 52° W, the eastem half of the West Greenland ice-free land area transected by Søndre Strømfjord. The principal objectives of the work were to map and describe the glacial and emerged marine deposits for a Quatemary map at 1:500 000 scale, and to collect material for establishing a radiometric chronology of former ice-margin positions and sea levels. In order to study as large an area as possible, the investigations north of Søndre Strømfjord and Sondrestrom Airbase were conducted by A. Weidick, the area south of this by N. W. Ten Brink.

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A pilot seismo-stratigraphic study on the West Greenland continental shelf

Rapport Grønlands Geologiske Undersøgelse ◽

10.34194/rapggu.v142.8054 ◽

1989 ◽

Vol 142 ◽

pp. 1-16

Author(s):

J.A Chalmers

Keyword(s):

Petroleum Industry ◽

Source Rocks ◽

Tectonic Activity ◽

The West ◽

West Greenland ◽

Main Site ◽

Half Graben ◽

Greenland Basin ◽

Seismic Sections ◽

Structural Closure

Seismo-stratigraphic interpretation of seismic sections dating from the mid-1970s has disclosed the existence of four megasequences of sediments, the oldest of which has not previously been reported from West Greenland. The basins containing these sediments developed as a series of coalescing half graben, in which the main site of tectonic activity changed with time. A structural closure of sufficient size to contain interesting quantities of hydrocarbons, given suitable source rocks, reservoir and seal, is identified. The study has shown that the evaluation of the West Greenland Basin during the 1970s was inadequate, and that abandonment of exploration by the petroleum industry may have been premature.

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Application of seismo-stratigraphic interpretation techniques to offshore West Greenland

Rapport Grønlands Geologiske Undersøgelse ◽

10.34194/rapggu.v140.8037 ◽

1988 ◽

Vol 140 ◽

pp. 64-66

Author(s):

J.A Chalmers

Keyword(s):

Pilot Study ◽

Seismic Data ◽

Seismic Interpretation ◽

Shelf Break ◽

The West ◽

Regional Geology ◽

West Greenland ◽

Oil Companies ◽

Greenland Basin ◽

Basement Ridge

A pilot study is being conducted to determine if the use of seismo-stratigraphic interpretation techniques can increase the understanding af the geology of offshore West Greenland in order to reassess the prospectivity of the area. During the period 1975 to 1979, a number of concessions offshore West Greenland were licensed to various consortia of oil companies to search for petroleum. Some 40 000 km of seismic data were acquired, all of which is now released. Five wells were drilled, all of them dry, and all concessions were relinquished by the industry by 1979. The regional geology of offshore West Greenland has been summarised by Manderscheid (1980) and Henderson et al. (1981). They show the West Greenland Basin to consist of fairly uniformly westward dipping sediments bordered near the shelf break by a basement ridge. These authors used what may be termed 'conventional' techniques of seismic interpretation. However, since that time the techniques of seismo-stratigraphy (Vail et al., 1977; Hubbard et al., 1985) have become established. They are now being applied to study seismic data acquired during the mid-1970s.

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Deep-Water Contourite Drifts in the West of North-China Platform

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.318.447 ◽

2013 ◽

Vol 318 ◽

pp. 447-452

Author(s):

Shun She Luo ◽

Zhen Zhong Gao ◽

You Bin He ◽

Qi Qi Lv ◽

Ying Meng

Keyword(s):

Deep Water ◽

North China ◽

The West ◽

North China Platform ◽

Middle Ordovician ◽

Contourite Drifts

The middle Ordovician of Pingliang area on the west margin of North-China platform is represented by a succession of deep-water sediments in which contourites are well-developed. Contour current deposits are well-developed. The contourites can be classified into:calcarenitic contourite, calcisiltitic contourite and calcilutitic contourite. Three typical contourite successions are recognized: complete contourite succession, incomplete contourite succession and contourite successions consisting only of calcarenitic contourites. According to the palaeocorrent and the palaeogeographic format analyse,carbonate contourite drift in the study area is unfolded crossing northwest-southeast, forwarding from southeast to northwest along the slope, and compared with other contourite drifts, it has some characteristics of coarser-grained sediment, thicker individual layers, and highly developed calcarenitic contourites and so on.

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