Pertrographic and related analyses of two samples identified as german blend coal and german homogenous coal submitted by the Sydney Steel Corporation, Nova Scotia. Project 03-1-3/17-5

1975 ◽  
Author(s):  
J G Jorgensen
Keyword(s):  
Nova Scotia ◽  
Two Samples ◽  
Steel Corporation

40Ar/39Ar dating in the Lochaber–Mulgrave area, northern mainland Nova Scotia: implications for timing of regional metamorphism and sediment provenance in the Late Devonian – Early Carboniferous Horton Group

2004 ◽  
Vol 41 (8) ◽  
pp. 987-996 ◽  
Author(s):  
P H Reynolds ◽  
S M Barr ◽  
C E White ◽  
P J Ténière
Keyword(s):  
Nova Scotia ◽  
Regional Metamorphism ◽  
Early Carboniferous ◽  
Fault System ◽  
Sediment Provenance ◽  
Late Devonian ◽  
The South ◽  
Two Samples ◽  
Meguma Terrane ◽  
Fusion Analysis

40Ar/39Ar dating of whole-rock samples and muscovite separates using age spectrum analysis, and of single muscovite grains using total fusion analysis, yields new insights into the timing of regional metamorphism and sediment provenance in the Late Devonian – Early Carboniferous Horton Group in the Lochaber–Mulgrave area of Nova Scotia. The time of regional metamorphism is constrained to ca. 340–335 Ma by whole-rock spectra from well-cleaved slate and shale samples from the lowermost Clam Harbour River and overlying Tracadie Road formations of the Horton Group. This ca. 340–335 Ma event may have been the result of burial and deformation of the Horton Group by older volcanic and sedimentary rocks of the Guysborough Group, which were overthrust from the south as the result of development of a positive flower structure at a restraining bend along the Cobequid–Chedabucto fault system, the boundary between the Meguma and Avalon terranes. Detrital muscovite ages of ca. 410–380 and ca. 500 Ma were obtained from single-grain analysis and from spectral analysis of separated grains. Whole-rock spectra for two samples from a mylonitic metasedimentary unit in the Cape Porcupine Complex yielded plateau ages of 364 ± 4 and 367 ± 4 Ma, providing a likely source for ca. 370–360 Ma detrital muscovite, ages that may be reflected in some of the age spectrum data. However, the Meguma terrane to the south is the most likely source for most of the detrital muscovite.

K–Ar isochron age and paleomagnetism of diabase along the trans-Avalon aeromagnetic lineament—evidence of Late Triassic rifting in Newfoundland

1980 ◽  
Vol 17 (4) ◽  
pp. 491-499 ◽  
Author(s):  
J. P. Hodych ◽  
A. Hayatsu
Keyword(s):  
Nova Scotia ◽  
Early Jurassic ◽  
Late Triassic ◽  
The North ◽  
Two Samples ◽  
Avalon Peninsula

A prominent aeromagnetic lineament crosses the Avalon Peninsula of Newfoundland from 46°50.4′N, 53°45.9′W to 47°22.1′N, 52°30.0′W. It is shown to be at least partly caused by diabase dikes of Late Triassic and possibly Early Jurassic age which are probably related to the Shelburne diabase dike and the North Mountain basalt, both of Nova Scotia. All are thought to have resulted from rifting which preceded opening of the Atlantic.Unmetamorphosed diabase was found at three sites along the trans-Avalon aeromagnetic lineament: as narrow sills at site 1 (46°58.0′N, 53°25.4′W), as a narrow dike at site 2 (47°4.7′N, 53°7.6′W), and as large angular boulders at site 3 (47°11.0′N, 52°52.2′W).For sites 1 and 2, analyses of seven diabase samples fall on a single K–Ar isochron whose intercept on the 40Ar/36Ar axis is at 215 ± 45 and whose slope gives a Late Triassic age of 201.1 ± 2.6 Ma. Analyses of two diabase samples from the Shelburne dike fall close to this isochron suggesting a similar age. Paleomagnetism adds support; the virtual paleopole measured for sites 1 and 2, using 12 oriented diabase samples demagnetized in 300 Oe (23 880 A/m) alternating field (AF), falls at 87.8°E, 72.9°N (dp = 3.0°, dm = 4.3°), close to the virtual paleopole reported for the Shelburne dike.For site 3, analyses of two samples fall on the K–Ar isochron reported for the North Mountain basalt, tentatively suggesting that the intrusion at site 3 occurred about 10 Ma later than at sites 1and 2.

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