Cambrian acritarchs from the Bourinot belt, Cape Breton Island, Nova Scotia: age and stratigraphic implications1This article is one of a series of papers published in CJES Special Issue: In honour of Ward Neale on the theme of Appalachian and Grenvillian geology.

2012 ◽  
Vol 49 (1) ◽  
pp. 289-307 ◽  
Author(s):  
Teodoro Palacios ◽  
Sören Jensen ◽  
Chris E. White ◽  
Sandra M. Barr
Keyword(s):  
Nova Scotia ◽  
Special Issue ◽  
Middle Cambrian ◽  
Cape Breton Island ◽  
Cape Breton

We present the first description of organic-walled microfossils from Cambrian strata of the Bourinot belt, central Cape Breton Island. Age-diagnostic acritarchs have been recovered from the Dugald and MacMullin formations and from probable levels within the upper part of the Eskasoni Formation, which permit detailed correlations with acritarch-based zones in Newfoundland and Spain. The assemblage of acritarchs from the Dugald Formation confirms earlier assignments to the early middle Cambrian eteminicus Zone, but it also indicates that the upper part of the formation belongs to the hicksi Zone of the Drumian Stage. Acritarchs from the MacMullin Formation provide the first biostratigraphic evidence that this unit extends into the forchhammeri Zone of the Guzhangian Stage. These acritarchs are present in the lower part of the MacMullin Formation, putting into question earlier identification of hicksi Zone trilobites in this unit and raising the possibility of an unconformity. The data from the Bourinot belt provide additional evidence for the biostratigraphic utility of acritarchs in the Cambrian Acado-Baltic province.

Upper Placentian—Branchian series of mainland Nova Scotia (middle-upper Lower Cambrian): Faunas, paleoenvironments, and stratigraphic revision

1995 ◽  
Vol 69 (3) ◽  
pp. 475-495 ◽  
Author(s):  
Ed Landing
Keyword(s):  
Nova Scotia ◽  
Lower Cambrian ◽  
Preliminary Evidence ◽  
Middle Cambrian ◽  
Cape Breton Island ◽  
Cape Breton ◽  
History Of ◽  
Placentia Bay ◽  
Stratigraphic Nomenclature ◽  
Eastern Massachusetts

Lithostratigraphy and depositional and epeirogenic history of the upper Placentian Series (Cuslett-Fosters Point Formations of the Bonavista Group) and Branchian Series (Brigus Formation) are identical in the northern Antigonish Highlands; Cape Breton Island; and eastern Placentia Bay, southeastern Newfoundland. Preliminary evidence suggests that the lower Middle Cambrian is present in the field area. A unified, uppermost Precambrian–Lower Cambrian, formation- and member-level nomenclature is appropriate to Avalonian North America, and the stratigraphic nomenclature of southeastern Newfoundland is applied in northern mainland Nova Scotia.Latest Placentian shoaling and deposition of a peritidal carbonate lithosome and unconformable onlap of the trilobite-bearing Branchian Series occurred in shallow Avalonian shale basins from eastern Massachusetts to central England.Uppermost Placentian Series faunas are very diverse in the Fosters Point Formation. Limited similarities with the South Australian Lower Cambrian are indicated by the presence of Camenella sp. cf. C. reticulosa, Conotheca australiensis, and Hyptiotheca sp., but these forms do not contribute to highly resolved correlation.Twenty-eight taxa are illustrated from the upper Placentian and Branchian Series. Caveacus rectus n. gen. and sp., a phosphatic problematicum, is limited to the upper Placentian Series. The oldest, skeletalized, macrophagous predators are the Pseudoconodontida and the later appearing Protoconodontida (n. orders). The Pseudoconodontida includes the Protohertzinacea n. superfamily and Strictocorniculacea n. superfamily (with the Rhombocorniculidae and Strictocorniculidae n. families). Strictocorniculum vanallerum n. gen. and sp. is described. The tommotiid family Sunnaginiidae emend. includes Eccentrotheca, Sunnaginia, Kulparina, and Jayceia deltiformis n. gen. and sp.

Middle Cambrian paleomagnetism of the Avalon Terrane in Cape Breton Island, Nova Scotia

Tectonics ◽  
1985 ◽  
Vol 4 (7) ◽  
pp. 629-651 ◽  
Author(s):  
Rex J. E. Johnson ◽  
Rob Van der Voo
Keyword(s):  
Nova Scotia ◽  
Middle Cambrian ◽  
Cape Breton Island ◽  
Cape Breton

Acritarchs from the MacLean Brook Formation, southeastern Cape Breton Island, Nova Scotia, Canada: New data on Middle Cambrian–Lower Furongian acritarch zonation

2009 ◽  
Vol 273 (1-2) ◽  
pp. 123-141 ◽  
Author(s):  
Teodoro Palacios ◽  
Sören Jensen ◽  
Sandra M. Barr ◽  
Chris E. White
Keyword(s):  
Nova Scotia ◽  
Middle Cambrian ◽  
Cape Breton Island ◽  
Cape Breton

40Ar/39Ar mineral ages from Kellys Mountain, Cape Breton Island, Nova Scotia: implications for the tectonothermal evolution of the Avalon composite terrane

1989 ◽  
Vol 26 (8) ◽  
pp. 1509-1516 ◽  
Author(s):  
J. Duncan Keppie ◽  
R. D. Dallmeyer
Keyword(s):  
Nova Scotia ◽  
Contact Aureole ◽  
Rapid Cooling ◽  
Middle Cambrian ◽  
Cape Breton Island ◽  
Cape Breton ◽  
Mineral Assemblages ◽  
Plutonic Complex ◽  
High Level

Hornblende from a diorite stock within the Kellys Mountain plutonic complex within the Avalon composite terrane, and hornblende, muscovite, and biotite from amphibolite and gneiss within the contact aureole record similar 40Ar/39Ar plateau ages of 493–498 Ma. These data indicate relatively rapid cooling through the contrasting temperatures appropriate for intracrystalline retention of argon in the different minerals. This is consistent with the relatively high level of intrusion of the pluton (3–10 km) suggested previously from the study of mineral assemblages developed in the contact aureole. These relationships suggest that intrusion of the Kellys Mountain complex took place at approximately 500 Ma, indicating an age close to the Cambro-Ordovician boundary. The complex may have formed in the same within-plate rifting regime as the Middle Cambrian Bourinot Group volcanic sequences exposed within the Avalon composite terrane.

Cambrian volcanism in Nova Scotia, Canada

1985 ◽  
Vol 22 (4) ◽  
pp. 599-606 ◽  
Author(s):  
J. B. Murphy ◽  
K. Cameron ◽  
J. Dostal ◽  
J. Duncan Keppie ◽  
A. J. Hynes
Keyword(s):  
Nova Scotia ◽  
Lower Cambrian ◽  
Basaltic Magma ◽  
Volcanic Rocks ◽  
Felsic Magma ◽  
Middle Cambrian ◽  
Cape Breton Island ◽  
Shallow Marine ◽  
Cape Breton ◽  
Pull Apart Basin

Cambrian volcanic rocks in Nova Scotia occur in small grabens or half grabens in the Avalon Zone (Composite Terrane) as part of a thin sequence of continental to shallow-marine Cambro-Ordovician rocks. In the northern Antigonish Highlands, the volcanic rocks occur mainly in the Lower Cambrian McDonalds Brook Group. In southern Cape Breton Island, they occur predominantly in the Middle Cambrian Bourinot Group. The chemistry of these volcanic rocks indicates that they are bimodal (basalts–rhyolites) and within plate. The basalts are alkalic in the Antigonish Highlands and tholeiitic in Cape Breton Island. The rising basaltic magma is postulated to have produced the felsic magma by anatexis of the crust. It is proposed that the Antigonish Highlands volcanic rocks erupted in a small pull-apart basin. A similar structural setting is probable in southern Cape Breton Island, but there the bounding faults are poorly exposed. These basins probably formed during a period of transpression in the last stages of the late Hadrynian Cadomian deformation.

Contrasting U–Pb ages from plutons in the Bras d'Or and Mira terranes of Cape Breton Island, Nova Scotia

1990 ◽  
Vol 27 (9) ◽  
pp. 1200-1208 ◽  
Author(s):  
S. M. Barr ◽  
G. R. Dunning ◽  
R. P. Raeside ◽  
R. A. Jamieson
Keyword(s):  
Nova Scotia ◽  
Close Similarity ◽  
Zircon Age ◽  
Middle Cambrian ◽  
Cape Breton Island ◽  
Early Ordovician ◽  
Late Precambrian ◽  
Cape Breton ◽  
Devonian Age

U–Pb dates from zircon, titanite, and monazite in plutons of the Bras d'Or and Mira terranes of southern Cape Breton Island, combined with 40Ar/39Ar and other radiometric age data, indicate that the Bras d'Or and Mira terranes had separate magmatic and metamorphic histories until at least the Middle Cambrian and possibly until the Devonian. The Bras d'Or Terrane is characterized by abundant late Precambrian (ca. 565–555 Ma) dioritic to granitic plutons, as exemplified by the Shunacadie granodiorite ([Formula: see text], U–Pb zircon). Early Ordovician granitic plutons, such as the Kellys Mountain leucogranite with a U–Pb (zircon) age of 498 ± 2 Ma, occur locally. Titanite and 40Ar/39Ar (hornblende) ages from plutons and metamorphic units suggest that widespread metamorphism may have occurred between these plutonic events and (or) during the Early Ordovician plutonism.Plutons in the Mira Terrane appear to have been emplaced at about 620 Ma or before, as exemplified by the Chisholm Brook granodiorite ([Formula: see text]), and to have been unaffected by younger thermal events, as indicated by close similarity of U–Pb (zircon and titanite) and 40Ar/39Ar (hornblende) ages. Plutons of Devonian age are localized in an easterly trending belt in the central part of the terrane. In contrast to the Bras d'Or Terrane, widespread latest Precambrian (ca. 565–555 Ma) to Early Ordovician plutonism and metamorphism appear to have been absent. It is unlikely that the Mira and Bras d'Or terranes were juxtaposed before the Early Ordovician.

Provenance of fossiliferous clasts in Carboniferous conglomerate, Isle Madame, southern Cape Breton Island, Nova Scotia

2006 ◽  
Vol 43 (3) ◽  
pp. 295-302
Author(s):  
Arthur J Boucot ◽  
Ed Landing ◽  
W Douglas Boyce ◽  
Sandra M Barr ◽  
Chris E White
Keyword(s):  
Nova Scotia ◽  
Lower Devonian ◽  
Middle Cambrian ◽  
Cape Breton Island ◽  
Cape Breton ◽  
Local Derivation ◽  
Middle Paleozoic ◽  
Marine Facies ◽  
Meguma Terrane ◽  
Western Isle

Fossiliferous clasts occur in Carboniferous conglomerate in the Horton Group on western Isle Madame and in the Mabou Group on eastern Isle Madame. Most of the clasts (21 of 23 examined) are calcareous siltstone and sandstone that contain Silurian – Lower Devonian faunas comparable to those in the Arisaig area, northern mainland Nova Scotia, although the lithologies are coarser grained and less calcareous than those of the Arisaig section. These middle Paleozoic faunas are well constrained to the Silurian (uppermost Llandovery through Pridoli) and lowest Devonian and are characteristic of those known from shallow siliciclastic-dominated platforms of the Avalon microcontinent in Wales and England. The remaining two clasts have abundant inarticulate brachiopod shells that indicate provenance from Middle Cambrian proximal marine facies on the Avalonian marginal platform. No clasts were found that are likely to have been derived from the Torbrook Formation, and thus from the Meguma terrane in southwestern Nova Scotia, as has been previously reported. The association of relatively large, reworked fossiliferous clasts in Carboniferous conglomerate on Isle Madame suggests local derivation from lower and middle Paleozoic units not presently exposed, although probably present as subcrop under the Carboniferous units, in southwestern Cape Breton Island and adjacent mainland Nova Scotia.

Cape Breton ruby, a new Canadian gemstone discovery, Cape Breton Island, Nova Scotia

2007 ◽  
Vol 30 (5) ◽  
pp. 279-286 ◽  
Author(s):  
David J. Mossman ◽  
James D. Duivenvoorden ◽  
Fenton M. Isenor
Keyword(s):  
Nova Scotia ◽  
Cape Breton Island ◽  
Cape Breton

RECOGNIZING CRYPTIC OROGENIC SUTURES IN COLLISIONAL OROGENS: THE EXAMPLE OF CAPE BRETON ISLAND, NOVA SCOTIA, CANADA

2018 ◽  
Author(s):  
Sandra M. Barr ◽  
◽  
Chris E. White ◽  
Deanne van Rooyen
Keyword(s):  
Nova Scotia ◽  
Cape Breton Island ◽  
Cape Breton ◽  
Collisional Orogens

DECIPHERING TECTONOMAGMATIC EVENTS IN THE GANDERIAN ASPY TERRANE OF CAPE BRETON ISLAND, NOVA SCOTIA, CANADA: JUXTAPOSED EARLY EDIACARAN THROUGH DEVONIAN ARC AND WITHIN-PLATE PLUTONS

2019 ◽  
Author(s):  
Sandra M. Barr ◽  
◽  
Chris E. White ◽  
Deanne van Rooyen ◽  
Gabriel Sombini dos Santos ◽  
...  
Keyword(s):  
Nova Scotia ◽  
Cape Breton Island ◽  
Cape Breton
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