Les erratiques de dolomie à Rivière-Blanche, côte sud de l'estuaire maritime du Saint-Laurent : un indicateur de transport glaciaire et glaciel

2002 ◽  
Vol 39 (8) ◽  
pp. 1239-1255 ◽  
Author(s):  
Jean-Claude Dionne
Keyword(s):  
Sedimentary Basin ◽  
Granite Gneiss ◽  
Canadian Shield ◽  
Ice Flow ◽  
Lawrence Estuary ◽  
North Shore ◽  
The North ◽  
South Shore ◽  
St Lawrence Estuary ◽  
Northwestern Area

At Rivière-Blanche, a locality on the south shore of the lower St. Lawrence estuary, the clayey and rocky shore zone is largely covered by stones of various sizes and lithologies, from local and far-distant sources. A survey exceeding 31 000 boulders indicates that 31% are Precambrian clasts (granite, gneiss, anorthosite, etc.) from the Canadian Shield located on the north shore of the St. Lawrence, 40 km from Rivière-Blanche, and 69% are Appalachian lithologies, mainly (45%) sandstone and graywacke. There are also 1.5% of dolostone erratics, a lithology not widespread in the Canadian Shield nor in the Appalachians. Of the 1242 clasts of the various varieties of dolostone erratics observed, the grey coral (Cladopora) dolostone erratics are restricted to the Rivière-Blanche area, whereas many other varieties are common to both shores of the St. Lawrence estuary. The most likely far-distance source is the Proterozoic Mistassini sedimentary basin, while a few varieties such as the coral dolostone erratics are from the Appalachian Siluro-Devonian formations, of which the nearest outcrops are located in the northwestern area of Lake Matapedia, 25–30 km south of Rivière-Blanche. Whatever their source, the dolostone erratics were first transported by a late Wisconsinian regional ice stream before being released by icebergs in the Goldthwait Sea. The coral dolostone (Clapodora) erratics provide additional evidence for a northward ice flow between Lake Matapedia and Rivière-Blanche during an early phase of deglaciation of the St. Lawrence Valley after the formation of an Appalachian ice divide located approximately at the latitude of Lac-au-Saumon.

scholarly journals La mer de Goldthwait au Québec

2010 ◽  
Vol 31 (1-2) ◽  
pp. 61-80 ◽  
Author(s):  
Jean-Claude Dionne
Keyword(s):  
Quebec City ◽  
The South ◽  
Lawrence Estuary ◽  
Marine Invasion ◽  
North Shore ◽  
The North ◽  
Upper Limit ◽  
South Shore ◽  
Anticosti Island ◽  
St Lawrence Estuary

The Goldthwait Sea is defined as the late- and post-Glacial marine invasion in the St. Lawrence Estuary and Gulf east of Québec City. In Québec, this sea has submerged an area of about 25 000 km2. The largest areas submerged are the north shore of the St. Lawrence between Les Escoumins and Blanc-Sablon, the south shore between Levis and Tourelles, and the Anticosti Island. The upper limit of the Goldthwait Sea varies from place to place. The Goldthwait Sea began 14 000 years ago and land emergence is still in progress, since the pre-Wisconsin marine level has not been recovered yet. For a better chronology, this long interval needs to be subdivided. Three main periods have been recognized: Goldthwaitian I, II and III. However, a geographical subdivision is also needed. Numerous shorelines were observed at various elevations throughout the area formely submerged by the Goldthwait Sea. However, only a few shorelines are well developed and extensive, and correlations between former shorelines are difficult to establish. Only three levels are widespead and common to the Estuary and parts of the Gulf. The isostatic recovery has been rapid during the first three thousand years after déglaciation of the area: about 75%.

scholarly journals Do Barrow's Goldeneyes, Bucephala islandica, Breed South of the St. Lawrence Estuary in the Gaspé Peninsula, Eastern Canada?

2010 ◽  
Vol 124 (2) ◽  
pp. 179
Author(s):  
Jean-François Ouellet ◽  
Pierre Fradette ◽  
Isabel Blouin
Keyword(s):  
North America ◽  
Breeding Season ◽  
Breeding Habitat ◽  
Eastern North America ◽  
Eastern Canada ◽  
Lawrence Estuary ◽  
North Shore ◽  
The North ◽  
Bucephala Islandica ◽  
St Lawrence Estuary

We report the first observations of Barrow's Goldeneyes south of the St. Lawrence estuary in typical breeding habitat during the breeding season. Until recently, the confirmed breeding locations for the species in Eastern North America were all located on the north shore of the Estuary and Gulf of St. Lawrence.

The structure of psoluthurin A, the major triterpene glycoside of the sea cucumber Psolusfabricii

1983 ◽  
Vol 61 (7) ◽  
pp. 1465-1471 ◽  
Author(s):  
François-Xavier Garneau ◽  
Jean-Luc Simard ◽  
Odette Harvey ◽  
John W. Apsimon ◽  
Michel Girard
Keyword(s):  
Triterpene Glycoside ◽  
Sea Cucumber ◽  
Chemical Data ◽  
Lawrence Estuary ◽  
North Shore ◽  
The North ◽  
Extraction And Purification ◽  
Physico Chemical ◽  
St Lawrence Estuary

The isolation of the major triterpene glycoside from the sea cucumber Psolusfabricii obtained from the north shore of the St. Lawrence estuary is described. Versatile extraction and purification procedures were used and physico-chemical data is presented in support of structure 1 for psoluthurin A.

Occurrence and general behavior of balaenopterid cetaceans summering in the St. Lawrence Estuary, Canada

1987 ◽  
Vol 65 (6) ◽  
pp. 1363-1376 ◽  
Author(s):  
Peggy L. Edds ◽  
J. Andrew F. Macfarlane
Keyword(s):  
Abundant Species ◽  
Humpback Whales ◽  
Lawrence Estuary ◽  
The Past ◽  
North Shore ◽  
The North ◽  
Minke Whales ◽  
Field Season ◽  
St Lawrence Estuary ◽  
Blue Whales

Baleen whale movements were monitored from a hillside on the north shore of the St. Lawrence Estuary from 28 June to 27 September 1979. No diurnal or tidal relationships were apparent for the two most abundant species, the minke and finback. Single minke whales were seen almost daily. Adult pairs were only seen on four dates, and no adult-calf pairs were observed. Twenty-two small minkes were observed; three were possibly 1st-year calves. Finbacks occurred singly and in groups, particularly later in the field season. Resightings of distinctive finbacks indicate that adult pairings are temporary. One finback had been seen in the area in 1973–1975. Adult–calf pairs and seven single juveniles were also seen. Observations of finbacks pursued by whale watchers provide evidence that some regulation of the rapidly growing whale-watching industry may be warranted. Blue whales and humpback whales were seen far less frequently than minkes and finbacks. The relative abundances of minke, finback, and humpback were similar to 1973–1974 in the same area: however, blue whales were seen far more frequently in the past.

Food of Double-crested Cormorants,Phalacrocorax auritus, in the Gulf and Estuary of the St. Lawrence River, Quebec, Canada

1998 ◽  
Vol 76 (4) ◽  
pp. 635-643 ◽  
Author(s):  
Jean-François Rail ◽  
Gilles Chapdelaine
Keyword(s):  
Phalacrocorax Auritus ◽  
Benthic Species ◽  
Sand Lance ◽  
Lawrence Estuary ◽  
North Shore ◽  
The North ◽  
Capelin Mallotus Villosus ◽  
Predatory Fishes ◽  
St Lawrence Estuary ◽  
St Lawrence River

Between 1994 and 1996, a total of 613 Double-crested Cormorant (Phalacrocorax auritus) regurgitations were collected at four colonies located in the St. Lawrence Estuary and one colony on the North Shore of the Gulf of St. Lawrence. The diet comprised a great variety of prey, with fishes well represented. Capelin (Mallotus villosus) and sand lance (Ammodytes sp.) together constituted most of the diet, (i.e., frequency of occurrence 66%, numerical frequency 68%, and volume 50%). Sand lance, which were nearly absent in regurgitations from the Estuary, were important in the diet of cormorants from the North Shore of the Gulf. At the North Shore colony, capelin were much more abundant in the diet in 1996 than in 1995, which correlates with independent fisheries data. In contrast to the results of previous studies of this cormorant's diet, our results show a preponderance of schooling fishes over benthic species. We suggest that this reflects a recent trend towards an increase in the abundance of schooling fishes in the St. Lawrence Estuary and Gulf. Overfishing of predatory fishes and oceanographic factors could be involved.

Habitat use and movements of postfledging American black ducks (Anas rubripes) in the St. Lawrence estuary, Quebec

1994 ◽  
Vol 72 (12) ◽  
pp. 2100-2104 ◽  
Author(s):  
David A. Clugston ◽  
Jerry R. Longcore ◽  
Daniel G. McAuley ◽  
Pierre Dupuis
Keyword(s):  
Habitat Use ◽  
Home Range Size ◽  
Hunting Season ◽  
Lawrence Estuary ◽  
Anas Rubripes ◽  
North Shore ◽  
The North ◽  
American Black ◽  
The Mean ◽  
St Lawrence Estuary

We used radiotelemetry to determine habitat use and movements of 38 female juvenile American black ducks (Anas rubripes) on the north shore of the St. Lawrence estuary, Quebec, from 28 August to 15 November 1991. Ducks separated into three groups based on habitat use: inland, estuarine, and those using a mixture of habitats. Ducks using mixed habitats used the greatest variety of habitat types, flew the greatest distances and most often between night roosts and day foraging areas, and were unlikely to be shot. The mean distance flown between night-use and day-use areas for all ducks increased nearly 50% after the hunting season began (overall mean = 6104 m, range 1500 – 26 384 m). Mean home range size was 27.6 ± 6.5 (SE) km2. Ducks exhibited stronger fidelity to wetlands used at night than to those used during the day. Ducks that were shot spent a high percentage of their time on the estuary (90.1 ± 7.4%) and exhibited high fidelity to a day-use area before the hunting season (73 ± 7.3%).

Preliminary interpretation of the first refraction arrivals in Gaspé from shots in Labrador and Quebec

1969 ◽  
Vol 6 (4) ◽  
pp. 771-774 ◽  
Author(s):  
Douglas S. Rankin ◽  
Ravi Ravindra ◽  
David Zwicker
Keyword(s):  
Upper Mantle ◽  
Arrival Time ◽  
The South ◽  
North Shore ◽  
The North ◽  
A Value ◽  
South Shore ◽  
Compressional Velocity ◽  
St Lawrence River

Previous work in the Gulf of St. Lawrence has yielded an unusually high upper-mantle compressional velocity. In the Gaspé area a more recent determination has yielded a value of 8.75 ± 0.20 km/s for an unreversed profile. The arrival time at a station on the north shore of the St. Lawrence River suggests that there is no major difference in velocity and depth relative to the south shore.

Petrochemical and stratigraphic aspects of North Mountain basalt from the north shore of the Bay of Fundy, Nova Scotia, Canada

1989 ◽  
Vol 26 (12) ◽  
pp. 2710-2717 ◽  
Author(s):  
John D. Greenough ◽  
Lois M. Jones ◽  
David J. Mossman
Keyword(s):  
Major Element ◽  
Sedimentary Rocks ◽  
Bay Of Fundy ◽  
Average Composition ◽  
North Shore ◽  
The North ◽  
Flow Units ◽  
Lateral Extent ◽  
South Shore ◽  
Magma Migration

Early Jurassic quartz-normative tholeiitic basalts occur in a series of fault blocks at four localities (Cap d'Or, Parrsboro, Five Islands, and Bass River) along the north shore of the Bay of Fundy. Major-element and trace-element data show that they represent outliers of the North Mountain basalt (NMB), which from the south shore of the Bay of Fundy are well-known. Diagnostic 87Sr/86Sr ratios (≈0.70609) indicate that a thick (>90 m) flow at Five Islands and Cap d'Or represents the lower unit of NMB, thus extending this single flow's lateral extent to 230 km. Thin flows overlying the thick flow at Cap d'Or suggest that the middle unit of NMB also occurs on the north shore. A thick flow at McKay Head (Parrsboro area) shows a variable Sr isotopic composition that is probably a result of metasomatism (with Rb addition) along the Cobequid fault. The average composition (0.70656) is similar to that of the upper unit of NMB. If the flow does represent the upper unit, then four thinner flows above it form an "overlying unit" not recognized along North Mountain. Although the nature of contacts between the middle and upper units was not observed, a lack of sedimentary rocks between all other flow units indicates that little or no sedimentation occurred between basalt eruptions. North shore basalts appear less mafic (more evolved) than south shore basalts, providing support for the hypothesis of differentiation during northeasterly magma migration through dykes that fed 230 km long fissure eruptions.

scholarly journals XI. Researches on the tides.—tenth series. on the laws of low water at the port of plymouth, and on the permanency of mean water

1839 ◽  
Vol 129 ◽  
pp. 151-161 ◽  
Keyword(s):  
High Water ◽  
Level Line ◽  
English Channel ◽  
Know How ◽  
North Shore ◽  
The North ◽  
South Shore ◽  
The Subject ◽  
The Mean ◽  
The Difference

In former communications to the Society, the laws of high water at Plymouth and other places have been the subject of my researches. These being obtained, the laws of low water are a subject of importance and interest on many accounts. The first ground of my pursuing this subject was the desire to ascertain how far the mean water , that is, the height midway between high and low water, is permanent during the changes which high and low water undergo. That it is approximately so at Ply­mouth, had been ascertained both by Mr. Walker and myself, by means of a com­parison of a short series of observations. But it was desirable to know with more exactness what was the real amount of this permanency, when, by using a long series of observations of high and low water, the irregularities arising from accident, and from taking imperfect cycles of inequalities, were eliminated. There was another reason which made this inquiry important at the present time. An operation has been recently carried on by the direction and at the expense of the British Association, with a view of ascertaining what surface ought to be taken as the permanent level of the sea. A Level Line has been carried with great care and accuracy from the north shore of Somerset to the south shore of Devon ; and the po­sition of this line has been fixed, so as to be recognised at any future time, by means of marks at Axmouth, at East Quantockshead, at Stolford, and at Portishead. This line has also been referred to the sea at its extremities ; and the observations show that the height of mean water coincides, at least very nearly, at different places, as well as at the same place at different times. While the difference of levels of low water at Axmouth on the English Channel, and Wick Rocks on the Bristol Channel, is not less than twelve feet; the mean water at those two places coincides in level within a few inches. In order to determine further what accuracy may be attained in this result, we are led to inquire what is the degree of permanency at one place. I may further add, that it cannot but be instructive to know how far the corrections of the height and time of low water, for lunar parallax and declination, agree in form and amount with the same corrections already obtained for high water.

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