Geology and geochemistry of the late Precambrian Coldbrook Group near Saint John, New Brunswick

1990 ◽  
Vol 27 (11) ◽  
pp. 1418-1430 ◽  
Author(s):  
K. L. Currie ◽  
G. N. Eby
Keyword(s):  
New Brunswick ◽  
Crustal Contamination ◽  
Geochemical Data ◽  
Bay Of Fundy ◽  
Sr Isotope ◽  
Magma Evolution ◽  
Volcanic Arc ◽  
Crustal Component ◽  
Pyroclastic Rocks ◽  
Late Precambrian

The late Precambrian Coldbrook Group comprises basal basaltic flows and pyroclastic rocks, fragmental andesitic to rhyolitic rocks, and minor capping sedimentary strata, all deformed and metamorphosed to prehnite–pumpellyite grade. Sr-isotope data indicate metasomatism, and probably deformation and metamorphism, took place long after deposition, possibly during major Carboniferous deformation of the Bay of Fundy region. Geochemical data suggest that the Coldbrook Group formed in a subduction-related ensialic volcanic-arc environment, although some specimens appear transitional to within-plate tholeiites. Magma evolution was dominated by fractionation of ilmenite, pyroxene, and plagioclase. Trace-element ratios suggest crustal contamination of virtually all Coldbrook Group rocks, with the amount of crustal component larger in the more salic portion. Comparison of data for the Coldbrook Group with data of other late Precambrian volcanic sequences in Atlantic Canada suggests that similar arc-related sequences underlie slightly younger, continental bimodal sequences in many Avalonian terranes.

Distribution and structure of coastal ichthyoplankton communities of the Bay of Fundy in southern New Brunswick, Canada

2021 ◽  
Vol 51 (1) ◽  
Author(s):  
Lou Van Guelpen ◽  
Claire Goodwin ◽  
Rebecca Milne ◽  
Gerhard Pohle ◽  
Simon Courtenay
Keyword(s):  
New Brunswick ◽  
Bay Of Fundy

Limnetic Zooplankton Assemblages in Atlantic Canada with Special Reference to Acidification

1986 ◽  
Vol 43 (2) ◽  
pp. 444-456 ◽  
Author(s):  
J. C. H. Carter ◽  
W. D. Taylor ◽  
R. Chengalath ◽  
D. A. Scruton
Keyword(s):  
Nova Scotia ◽  
New Brunswick ◽  
Fish Predation ◽  
Low Ph ◽  
Buffering Capacity ◽  
The Other ◽  
Bay Of Fundy ◽  
Factor Scores ◽  
Multiple Discriminant Analysis ◽  
Biological Factors

Crustacean and rotifer plankton assemblages of 93 lakes in Labrador, 107 in Newfoundland, and 142 in New Brunswick – Nova Scotia were investigated for evidence of correlations with lake morphometric, chemical, or biological factors. Labrador assemblages were almost completely lacking in identifiable structure. Newfoundland species clustered into two groups of different body size, suggesting the influence of fish predation. Only one species in Labrador and Newfoundland was significantly correlated with a derived factor related to lake water buffering capacity. New Brunswick – Nova Scotia species clustered into two groups, one featuring significant positive and the other significant negative correlations with the buffering factor. From this we conclude that acidification is having an impact on the limnetic zooplankton of these two provinces. Multiple discriminant analysis was used to demonstrate that New Brunswick – Nova Scotia lakes differing in their buffering capacity were also distinct in zooplankton composition. Lakes with low factor scores (low pH, alkalinity, and calcium) were mainly located in the Bay of Fundy region; this area has above average fog and precipitation, and lies within the summer air flow carrying pollutants from the south.

Genesis of the Wuxing Pt–Pd-rich Cu–Ni sulfide deposit in the eastern Central Asian Orogenic Belt: evidences from geochronology, elemental geochemistry, and Sr–Nd–Hf isotopic data

2019 ◽  
Vol 56 (4) ◽  
pp. 380-398 ◽  
Author(s):  
Jing-gui Sun ◽  
Yun-peng He ◽  
Ji-long Han ◽  
Zhong-yu Wang
Keyword(s):  
Crustal Contamination ◽  
Early Period ◽  
Orogenic Belt ◽  
Central Asian Orogenic Belt ◽  
Geochemical Data ◽  
Sulfide Deposit ◽  
Late Period ◽  
Enriched Mantle ◽  
Central Asian ◽  
T Values

The Wuxing Pt–Pd-rich Cu–Ni sulfide deposit in Heilongjiang Province, Northeast China, is located to the northeast of the Dunhua–Mishan fracture of the eastern Central Asian Orogenic Belt. The mafic–ultramafic complex consist of early-period hornblende–olivine pyroxenite, diopsidite, and hornblende pyroxenite and late-period gabbro and diabase units. An early-period hornblende pyroxenite yielded a zircon U–Pb age of 208.2 ± 2.6 Ma and a late-period diabase yielded a U–Pb age of 205.6 ± 1.1 Ma, with zircon εHf(t) values of +1.24 to +8.13. The early- and late-period lithofacies are relatively enriched in LILE (Rb, Ba, and Sr) and LREE, and variably depleted in HFSE (Nb, Ta). The whole-rock and single-mineral analyses of the early-period lithofacies yield (87Sr/86Sr)i ratios of 0.7055–0.7083 and εNd(t) ratios of −7.98–+3.10. These geochemical data suggest that the parental magmas of the Wuxing complex are high-Mg subalkaline basaltic in nature and were derived from an enriched mantle source. The magmas chamber formed after the injection of magma into the crust along with crustal contamination, producing early crystalline minerals and ore-bearing magmas. The rupturing of the magma chamber released evolved magmas, which then ascended and generated Pt–Pd-bearing lithofacies and Cu–Ni sulfide orebodies by fractional crystallization, accumulation, and liquation. During the late period, the residual magma invaded the early lithofacies and Cu–Ni orebodies. The fluids exsolved from the gabbroic magmas concentrated the mineralized metal elements and enhanced the precipitation of Pt–Pd-bearing veinlet-disseminated orebodies and Pt–Pd–Cu–Ni orebodies.

Origin of the Ordovician Mansehra granite in the NW Himalaya, Pakistan: constraints from Sr–Nd isotopic data, zircon U–Pb age and Hf isotopes

2018 ◽  
Vol 481 (1) ◽  
pp. 277-298 ◽  
Author(s):  
Masatsugu Ogasawara ◽  
Mayuko Fukuyama ◽  
Rehanul Haq Siddiqui ◽  
Ye Zhao
Keyword(s):  
Granitic Magma ◽  
Geochemical Data ◽  
Large Contribution ◽  
Crustal Material ◽  
Sr Isotope ◽  
Nw Himalaya ◽  
Nd Isotope ◽  
Isotope Data ◽  
Late Neoproterozoic ◽  
T Values

AbstractThe Mansehra granite in the NW Himalaya is a typical Lesser Himalayan granite. We present here new whole-rock geochemistry, Rb–Sr and Sm–Nd isotope data, together with zircon U–Pb ages and Hf isotope data, for the Mansehra granite. Geochemical data for the granite show typical S-type characteristics. Zircon U–Pb dating yields 206Pb/238U crystallization ages of 483–476 Ma. The zircon grains contain abundant inherited cores and some of these show a clear detrital origin. The 206Pb/238U ages of the inherited cores in the granite cluster in the ranges 889–664, 1862–1595 and 2029 Ma. An age of 664 Ma is considered to be the maximum age of the sedimentary protoliths. Thus the Late Neoproterozoic to Cambrian sedimentary rocks must be the protolith of the Mansehra granitic magma. The initial Sr isotope ratios are high, ranging from 0.7324 to 0.7444, whereas the εNd(t) values range from −9.2 to −8.6, which strongly suggests a large contribution of old crustal material to the protoliths. The two-stage Nd model ages and zircon Hf model ages are Paleoproterozoic, indicating that the protolith sediments were derived from Paleoproterozoic crustal components.

Pattern of recent vertical crustal movements in Maritime Canada

1976 ◽  
Vol 13 (5) ◽  
pp. 661-667 ◽  
Author(s):  
Petr Vaníček
Keyword(s):  
New Brunswick ◽  
Sea Level ◽  
Bay Of Fundy ◽  
Vertical Movements ◽  
Crustal Movements ◽  
First Order ◽  
Level Data ◽  
Velocity Surface ◽  
Maritime Canada ◽  
Vertical Crustal Movements

A surface depicting linear vertical movements in Maritime Canada was computed from sea-level data recorded by 8 tide guages and 308 mostly disjoint, relevelled segments of the first-order Canadian levelling network. Owing to the sparsity of the available data and their distribution, the velocity surface must be regarded as indicative of the crude features only. The indications are that there is a west-northwest trending belt of faster subsidence across the eastern end of the Bay of Fundy, and that there may be an area of uplift in northeastern New Brunswick. Although the faster subsidence around the eastern Bay of Fundy seems to be well established now, more data are needed to prove or dispel the existence of the indicated uplift.

scholarly journals Backscatter strength and shaded seafloor relief, Bay of Fundy, sheet 11, offshore Nova Scotia - New Brunswick

2011 ◽  
Author(s):  
B J Todd ◽  
J Shaw ◽  
D R Parrott ◽  
J E Hughes Clarke ◽  
D Cartwright ◽  
...  
Keyword(s):  
Nova Scotia ◽  
New Brunswick ◽  
Bay Of Fundy

scholarly journals Backscatter strength and shaded seafloor relief, Bay of Fundy, sheet 3, offshore Nova Scotia - New Brunswick

2011 ◽  
Author(s):  
B J Todd ◽  
J Shaw ◽  
D R Parrott ◽  
J E Hughes Clarke ◽  
D Cartwright ◽  
...  
Keyword(s):  
Nova Scotia ◽  
New Brunswick ◽  
Bay Of Fundy
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