scholarly journals Stratigraphic and geochemical constraints on the relative age of the Margaree Shear Zone in western Cape Breton Island, with implications for the early evolution of the Maritimes Basin

10.4138/2075 ◽  
1996 ◽  
Vol 32 (1) ◽  
Author(s):  
Gregory Lynch
Keyword(s):  
Shear Zone ◽  
Early Evolution ◽  
Western Cape ◽  
Cape Breton Island ◽  
Relative Age ◽  
Cape Breton ◽  
Maritimes Basin ◽  
Geochemical Constraints

The age of igneous and metamorphic events in the western Cape Breton Highlands, Nova Scotia

1986 ◽  
Vol 23 (12) ◽  
pp. 1891-1901 ◽  
Author(s):  
R. A. Jamieson ◽  
O. van Breemen ◽  
R. W. Sullivan ◽  
K. L. Currie
Keyword(s):  
Metamorphic Rocks ◽  
Western Cape ◽  
Cape Breton Island ◽  
Late Proterozoic ◽  
The North ◽  
Cape Breton ◽  
Gneiss Complex ◽  
Form Part ◽  
Plutonic Rocks ◽  
High Level

Plutonic rocks of four different ages have been recognized in the Cape Breton Highlands on the basis of U–Pb dating of zircons. Two plutons, the North Branch Baddeck River leucotonalite [Formula: see text] and the Chéticamp pluton (550 ± 8 Ma), give dates that fall within the range of Late Proterozoic to Cambrian ages considered characteristic of the Avalon tectonostratigraphic zone of the eastern Appalachians. Late Ordovician to Silurian tonalite (Belle Côte Road orthogneiss, 433 ± 20 Ma) was metamorphosed, deformed, and incorporated into the central Highlands gneiss complex by approximately 370–395 Ma. High-level subvolcanic plutons (Salmon Pool pluton, [Formula: see text]) postdate all metamorphic rocks in the area. The presence of the older plutons is consistent with interpretation that the Cape Breton Highlands form part of the Avalon zone, but the presence of Ordovician–Silurian plutonic rocks and Devonian amphibolite-facies metamorphism is anomalous in comparison with the Avalon zone of Newfoundland and southeastern Cape Breton Island. Terranes with similar Late Proterozoic to mid-Paleozoic plutonic and metamorphic histories form a discontinuous belt along the northwest side of the Avalon zone southwest of Cape Breton Island. These rocks probably reflect events during and after the accretion of the Avalon zone to North America.

Allerød–Younger Dryas Coleoptera from western Cape Breton Island, Nova Scotia, Canada

1996 ◽  
Vol 33 (1) ◽  
pp. 33-41 ◽  
Author(s):  
Randall F. Miller
Keyword(s):  
Nova Scotia ◽  
Younger Dryas ◽  
Late Glacial ◽  
Cold Climate ◽  
Western Cape ◽  
Cape Breton Island ◽  
Cape Breton ◽  
Beetle Assemblages ◽  
Climate Indicator ◽  
Younger Dryas Event

Studies of Coleoptera remains from two late-glacial sites on Cape Breton Island, Nova Scotia, Canada, present a picture of the paleoenvironment and paleoclimate during the Allerød–Younger Dryas transition in the Maritimes region. They provide evidence for the Younger Dryas event in northeastern North America. Between 11 300 and 10 800 BP, the beetle assemblages at the Campbell site are typical of faunas of the modern middle to northern boreal forest. The West Mabou site contains beetle fossils younger than 10 900 BP, possibly as young as 10 500 BP, extending into the time period of the Younger Dryas, dated from 10 800 to 10 000 BP in the Maritimes. A "cold climate" indicator recognizable in the beetle fauna, Olophrum boreale, occurs in relative abundance and provides an interesting comparison with sites in Europe where the same northern boreo-montane species is evident at the beginning of the Younger Dryas.

scholarly journals Reactivation of the Eastern Highlands Shear Zone, Cape Breton Island, Appalachian Orogen

2019 ◽  
Author(s):  
N Piette-Lauzière ◽  
R Graziani ◽  
K P Larson ◽  
D A Kellett
Keyword(s):  
Shear Zone ◽  
Cape Breton Island ◽  
Cape Breton ◽  
Appalachian Orogen ◽  
Eastern Highlands

Late Devonian – Early Carboniferous volcanism in western Cape Breton Island, Nova Scotia

1984 ◽  
Vol 21 (7) ◽  
pp. 762-774 ◽  
Author(s):  
Marie-Claude Blanchard ◽  
Rebecca A. Jamieson ◽  
Elizabeth B. More
Keyword(s):  
Tectonic Setting ◽  
Early Carboniferous ◽  
Alluvial Fan ◽  
Late Devonian ◽  
Fluvial Sediments ◽  
Western Cape ◽  
Cape Breton Island ◽  
The North ◽  
Cape Breton ◽  
Geochemical Studies

The Fisset Brook Formation of western Cape Breton Island and its equivalents at MacMillan Mountain and the north Baddeck River are examples of Late Devonian and Early Carboniferous volcanic sequences associated with the formation of post-Acadian successor basins in the northeastern Appalachians. They consist of bimodal basalt–rhyolite suites interbedded with alluvial fan, lacustrine, and rare fluvial sediments. The earliest volcanic products are rhyolites and somewhat evolved basalts associated with coarse sediments, followed by tholeiitic to transitional basalt flows interlayered with lacustrine-type deposits. Geochemical studies on the Fisset Brook Formation indicate extensive remobilization of alkalies, Ca, Rb, and Sr, making these elements inappropriate for determining tectonic setting or magmatic affinity. Use of less mobile elements (Ti, Nb, Y, and Zr) suggests that the basalts are tholeiitic and that the apparent alkalinity of the type section lavas is a result of alteration. We conclude that volcanism in western Cape Breton Island started at MacMillan Mountain and migrated westwards, probably towards the centre of the deepening Magdalen Basin.

Deglaciation of Port Hood Island, Nova Scotia

1974 ◽  
Vol 11 (10) ◽  
pp. 1357-1365 ◽  
Author(s):  
J. Terasmae
Keyword(s):  
Nova Scotia ◽  
Radiocarbon Dating ◽  
Climatic Conditions ◽  
Western Cape ◽  
Cape Breton Island ◽  
Cape Breton ◽  
Soil Creep ◽  
Palynological Study ◽  
Surficial Deposits

A palynological study and radiocarbon dating of surficial deposits on Port Hood Island, Nova Scotia, have indicated that deglaciation occurred more than 11 000 yr B.P., and that the presence of an 'upper till' in local depressions is attributable to soil-creep processes under cold and wet climatic conditions some 11 000 to 10 000 yr B.P. No evidence was found of an ice advance younger than 11 000 yr B.P. in western Cape Breton Island.

Determination of nearshore geologic structure off western Cape Breton Island, Nova Scotia, using high-resolution marine magnetics

2002 ◽  
Vol 39 (9) ◽  
pp. 1299-1312 ◽  
Author(s):  
Sonya A Dehler ◽  
D Patrick Potter
Keyword(s):  
Nova Scotia ◽  
High Resolution ◽  
Transition Zone ◽  
Magnetic Data ◽  
Magnetic Observatory ◽  
Western Cape ◽  
Offshore Structure ◽  
Seismic Reflection Data ◽  
Cape Breton Island ◽  
Cape Breton

New high-resolution magnetic data have been acquired along the coast of western Cape Breton Island near Cheticamp, Nova Scotia, in a transition zone between exposed, elevated basement of the Cape Breton highlands and the adjacent Carboniferous sediment-filled Magdalen Basin. These data were collected to provide continuity between the mapped onshore geology and the geophysical-based interpretations of offshore structure. Separation of the geologic component of the data from the effects of diurnal and other variations in the Earth's magnetic field was made difficult by recording problems at the nearby base recording station. Careful correlation of the fragmented station signal with records from a nearby permanent magnetic observatory enabled a reasonable diurnal signal to be synthesized and applied successfully to the data. Additional processing and filtering helped to enhance small anomalies in the data. Several low-amplitude, fairly linear magnetic anomalies are visible in the reduced anomaly data, generally trending north to northwest away from the coastline. Small-amplitude lineations in the offshore at Cheticamp are associated with folded, tilted, or faulted strata imaged on coincident seismic reflection data and are interpreted as representing juxtaposed units of Carboniferous strata. Other small anomalies appear to represent shallow contacts between intrusive or metasedimentary rocks visible in outcrops near the coast. A stronger, coast-parallel anomaly that extends across the study area from a regional magnetic high in the north is coincident with an offset in basement rocks or deeper strata beneath Carboniferous basin fill. This anomaly may mark part of the faulted transition zone between the elevated highlands of northwestern Cape Breton Island and the Magdalen Basin depocentre.

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