Paleomagnetism and K–Ar isochron dates of Early Jurassic basaltic flows and dikes of Atlantic Canada

1988 ◽  
Vol 25 (12) ◽  
pp. 1972-1989 ◽  
Author(s):  
J. P. Hodych ◽  
A. Hayatsu
Keyword(s):  
Nova Scotia ◽  
Recent Time ◽  
Early Jurassic ◽  
Eastern North America ◽  
Bay Of Fundy ◽  
Atlantic Canada ◽  
North Shore ◽  
The North ◽  
Boundary Date ◽  
Newark Supergroup

K–Ar isochron dates of 193 ± 2, 189 ± 3, and 191 ± 2 Ma are reported for the Shelburne dike of Nova Scotia, the Avalon dike of Newfoundland, and the Caraquet dike of New Brunswick, respectively. These major tholeiitic dikes agree in radiometric date with the North Mountain Basalt of Nova Scotia and with other tholeiitic flows of the Newark Supergroup that have been paleontologically assigned to the Hettangian. However, further work is needed to resolve the discrepancy between the Triassic–Jurassic boundary date of 193 ± 6 Ma suggested by the Newark Supergroup flows and the boundary dates of 204–213 Ma adopted in recent time scales.The North Mountain Basalt flows at nine sites on the north shore of the Bay of Fundy are shown to have likely magnetized during initial cooling, yielding an Hettangian virtual paleopole at 66°N, 72°E (dp = 9°, dm = 14°). New paleomagnetic results are also reported for the Caraquet and Avalon dikes.The virtual paleopoles from Hettangian flows and dikes of Atlantic Canada lie on average ~11 °north of the virtual paleopoles from Hettangian flows of the northeastern United States. This discrepancy is likely due to insufficient averaging out of paleosecular variation and demonstrates that caution is needed in paleomagnetically correlating among the Early Jurassic flows and intrusions of eastern North America.

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.

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.

Deep seismic reflection data from the Bay of Fundy and Gulf of Maine: tectonic implications for the northern Appalachians

1991 ◽  
Vol 28 (7) ◽  
pp. 1096-1111 ◽  
Author(s):  
C. E. Keen ◽  
W. A. Kay ◽  
D. Keppie ◽  
F. Marillier ◽  
G. Pe-Piper ◽  
...  
Keyword(s):  
Nova Scotia ◽  
Seismic Reflection ◽  
Gulf Of Maine ◽  
Deep Penetration ◽  
United States Geological Survey ◽  
Bay Of Fundy ◽  
Seismic Reflection Data ◽  
The North ◽  
Geological Features ◽  
Lower Crustal

Three deep-penetration seismic reflection profiles were collected off southwest Nova Scotia to determine the crustal structure and geometry beneath the Avalon and Meguma zones of the Appalachian Orogen in Canada. Onshore geological features have been traced seawards using new gravity and magnetic anomaly maps. The seismic data can also be correlated with the previous United States Geological Survey profile in the central Gulf of Maine.Two seismically distinct lower crustal blocks are identified: the Avalon and Sable lower crustal blocks, separated by a major north-dipping reflection zone that cuts the entire crust. The recognition of the Sable block adds a fourth block to the three already identified in the Canadian Appalachians. The Sable block is overlain by the Meguma Zone. The Avalon Zone overlies at least the northern part of the Avalon lower crustal block. Although offshore extension of geological features is not unequivocal, it appears that a north-dipping reflection zone southwest of Nova Scotia marks the site of Devonian thrusting of Avalon Zone over Meguma Zone. In the Bay of Fundy to the north, two south-dipping reflection zones are interpreted as major thrusts, possibly placing Avalon lower crust over a unit with different tectonic affinities. The Fundy Fault is a Carboniferous thrust within the Avalon block along the coast of New Brunswick; this was reactivated during Mesozoic extension as a transtensional fault. Extensional displacement farther southwest was probably accommodated along east-west-trending faults and small rift basins associated with them.

A Virus Disease and Introduced Parasites as Factors Controlling the European Spruce Sawfly, Diprion hercyniae (Htg.), in Central New Brunswick

1957 ◽  
Vol 89 (8) ◽  
pp. 371-378 ◽  
Author(s):  
F. T. Bird ◽  
D. E. Elgee
Keyword(s):  
Nova Scotia ◽  
New Brunswick ◽  
New Hampshire ◽  
Virus Disease ◽  
Spruce Forests ◽  
North Shore ◽  
The North ◽  
Gaspe Peninsula ◽  
Gaspé Peninsula ◽  
St Lawrence River

An outbreak of the European spruce sawfly, Diprion hercyniae (Htg.), was discovered in the Gaspé Peninsula in 1930. By 1938, heavy infestations had developed west of the Gaspé Peninsula in Quebec, throughout New Brunswick and northern Maine, and in parts of Vermont and New Hampshire. Moderate to light infestations occurred through all other parts of the spruce forests of this region and extended from Nova Scotia, to the north shore of the St. Lawrence River, and west to Ontario.

scholarly journals Natural history of the terrestrial green alga, Prasiola crispa (Trebouxiophyceae), and associated Herring Gulls on Brier Island, Nova Scotia

2017 ◽  
Vol 49 (1) ◽  
pp. 49
Author(s):  
David J. Garbary ◽  
Nicholas M. Hill
Keyword(s):  
Nova Scotia ◽  
Coastal Wetland ◽  
Larus Argentatus ◽  
Bay Of Fundy ◽  
Nutrient Inputs ◽  
Herring Gulls ◽  
The North ◽  
Prasiola Crispa ◽  
History Of ◽  
First Time

The local distribution of Prasiola crispa is reported for the first time in Nova Scotia. It was common on emergent basalt outcrops in a coastal wetland on the Bay of Fundy shores of Brier Island. The alga was present on 19 of 102 basalt outcrops in one of the breeding colonies of the Herring Gull, Larus argentatus, and was only associated with basalt outcrops with gull feces. Patches of P. crispa were typically associated with the north facing slopes of the rock or were present in depressions or parts of the rock shaded by adjacent vegetation. At Western Light, the gulls are both facilitating the presence of P. crispa and acting as ecosystem engineers by nesting in the adjoining vegetation where their trampling and nutrient inputs are modifying the surrounding wetland ecosystem. 

The deglaciation of Atlantic Canada as reconstructed from the postglacial relative sea-level record

1982 ◽  
Vol 19 (12) ◽  
pp. 2232-2246 ◽  
Author(s):  
Garry Quinlan ◽  
Christopher Beaumont
Keyword(s):  
Sea Level ◽  
Large Scale ◽  
Glacial Maximum ◽  
Atlantic Canada ◽  
Relative Sea Level ◽  
North Shore ◽  
The North ◽  
Exact Position ◽  
Late Wisconsinan ◽  
Ice Morphology

The post-Wisconsinan relative sea-level record from Atlantic Canada is used to reconstruct the morphology of late Wisconsinan age ice cover during its retreat from the Atlantic region. The proposed reconstruction has little or no grounded ice in the southern Gulf of St. Lawrence, an ice dome over the north shore of the St. Lawrence, and thin ice, often less than 1 km thick, over much of the rest of the area. A sensitivity analysis shows that the proposed reconstruction is not unique in its ability to account for the relative sea-level record but that the thickness of ice in any individual area of the reconstruction is unlikely to be in error by more than a factor of two. The exact position of the ice margin in some areas is not well constrained by the model; an example is in southeastern Newfoundland.The numerical model used to relate ice morphology to postglacial relative sea level assumes that the ice sheets are isostatically equilibrated at the glacial maximum and, therefore, that load changes associated with earlier ice-sheet growth may be ignored. This assumption is shown to be reasonable. The same rapid relaxation of the Earth that allows one to ignore the effects of glacial accumulation, however, prohibits one from recognizing the effects of large-scale ablation that may have occurred prior to the assumed glacial maximum. For this reason the proposed reconstruction may be representative of only a late stage in the ablation of much more extensive and thicker ice sheets.Surfaces of relative sea level are presented for Atlantic Canada at various times in the past. These surfaces coincide with observational data where such data exist and are felt to provide reasonable estimates of relative sea level at all other locations for at least the last 13 000 years.

scholarly journals First visual record of rare purple-colored dogwhelks (Nucella lapillus) on the Atlantic coast of Nova Scotia, Canada

F1000Research ◽  
2017 ◽  
Vol 5 ◽  
pp. 2435
Author(s):  
Sonja M. Ehlers ◽  
Julius A. Ellrich
Keyword(s):  
Nova Scotia ◽  
Field Experiments ◽  
Atlantic Coast ◽  
Rocky Intertidal ◽  
Bay Of Fundy ◽  
Nucella Lapillus ◽  
Shell Color ◽  
The North ◽  
Intertidal Gastropod ◽  
Visual Record

The dogwhelk Nucella lapillus is a rocky intertidal gastropod of the North Atlantic coast. Individual shell color varies. Common colors range between white and brown, with darker dogwhelks being more affected by heat stress than lighter-colored conspecifics. Other reported shell colors are purple, black, mauve, pink, yellow, and orange from UK coasts, red and gray from the Bay of Fundy coast of New Brunswick and Nova Scotia (Canada), and purple, black, gray, yellow, and orange from the coasts of Maine and Massachusetts (USA), with purple being considered as a rare color. On the Atlantic coast of Nova Scotia, dogwhelks are active from April until November, but information on dogwhelk shell color is missing for this coast. On 16 June 2016, we found two purple-colored dogwhelks in the mid-to-high intertidal zone of a moderately wave-exposed rocky shore near Duncans Cove, on the Atlantic coast of Nova Scotia while collecting dogwhelks (n= 1000) during low tide for manipulative field experiments. All other dogwhelks collected on that day were of common white and brown colors. During earlier dogwhelk collections in Atlantic Nova Scotia (between 2011-2013) and field surveys in Duncans Cove (between 2014-2016), we did not find any purple-colored dogwhelks, indicating the rareness of this color in that region. Apparently, our observations provide the first visual record of rare purple-colored dogwhelks on the Atlantic coast of Nova Scotia, Canada.

New records of Melyridae (Coleoptera) from the Maritime Provinces of Canada

2005 ◽  
Vol 137 (3) ◽  
pp. 325-327 ◽  
Author(s):  
Christopher G. Majka
Keyword(s):  
Nova Scotia ◽  
New Brunswick ◽  
North American ◽  
New Records ◽  
Atlantic Canada ◽  
Maritime Provinces ◽  
The North ◽  
The World

The Melyridae (soft-winged flower beetles) are a diverse, abundant, and widespread family of beetles found throughout the world, with more than 300 genera and 6000 species worldwide (Mayor 2002). Melyrids are particularly abundant in dry, temperate regions of the world. Mayor's (2002) synopsis of the North American fauna includes 58 genera and 520 species. Bright (1991) tabulates 49 species in 14 genera in the Canadian fauna. Only one species, the introduced Palearctic Malachius aeneus (L.), was reported for Atlantic Canada, with records in New Brunswick, Nova Scotia, and Newfoundland.

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