First Middle Ordovician biota from southern New Brunswick: stratigraphic and tectonic implications for the evolution of the Avalon continent

2003 ◽  
Vol 40 (5) ◽  
pp. 715-730 ◽  
Author(s):  
Ed Landing ◽  
Stephen R Westrop ◽  
Dong Hee Kim
Keyword(s):  
New Brunswick ◽  
Shallow Water ◽  
Iron Ore ◽  
Bay Of Fundy ◽  
Thermal Alteration ◽  
Marine Fauna ◽  
Lower Paleozoic ◽  
Middle Ordovician ◽  
Tectonic Implications ◽  
Quartz Arenite

A limestone boulder in the Triassic Lepreau Formation near Saint John, New Brunswick, has yielded the first diverse marine fauna from the sub-Caradoc Ordovician of the western Avalon continent. This fauna includes the first Arenig conodonts recovered from Avalon and represents an unexposed interval in southern New Brunswick. Association of the conodonts Drepanoistodus and Baltoniodus and the trilobites Neseuretus, Nileus, and Stapeleyella emphasizes the faunal dissimilarity of Avalon and Laurentia through the late Middle Ordovician. Extension of the ranges of Neseuretus cf. Neseuretus parvifrons and Stapeleyella from Britain into New Brunswick further emphasizes that "eastern" and "western" Avalon were confluent parts of a unified, insular Avalon continent that originated in the latest Precambrian. This fauna correlates with the lower Amorphognathus (Lenodus) variabilis Zone (Kundan Stage) of Baltica and the terminal Arenig (upper Middle Ordovician; lower Darriwilian Stage) of Avalonian Britain. Available evidence suggests that an Arenig cover sequence with local shallow-water hematitic iron ore, quartz arenite, and rare limestone extended across the Avalonian marginal and inner platforms from eastern Newfoundland to the Boston, Massachusetts, region. This "western" Avalonian Arenig shows the greatest similarity with the Arenig of the Welsh Borderlands. Phosphatic fossils from the boulder have a thermal alteration index much lower than that of nearby lower Paleozoic outcrops and suggest derivation of the boulder from a weakly heated Avalonian succession brought into the Bay of Fundy region by post-Ordovician transcurrent faulting.

Paleogeography of Northwestern New Brunswick during the Llandovery: a Study of the Provenance of the Siegas Formation

1971 ◽  
Vol 8 (2) ◽  
pp. 196-203 ◽  
Author(s):  
Terence Hamilton-Smith
Keyword(s):  
New Brunswick ◽  
Volcanic Rocks ◽  
Source Area ◽  
Potassium Feldspar ◽  
Source Rocks ◽  
Middle Ordovician ◽  
Quartz Arenite ◽  
Taconic Orogeny ◽  
Continuous Sedimentation ◽  
Mafic Volcanism

The Siegas Formation of northwestern New Brunswick and northeastern Maine is composed mainly of sandstone and slate and has yielded fossils of early Llandovery age. It conformably overlies older rocks, indicating that there was continuous sedimentation in the Siegas area during the time of the Taconic orogeny. The formation consists of the three laterally equivalent facies, the lithic wacke, the quartz arenite, and the arkosic facies. Sandstones of the lithic wacke facies are made up mainly of mafic volcanic grains and their decomposition products: sodic plagioclase, angular quartz, and pyroxene. Sandstones of the quartz arenite facies consist mainly of medium-grained rounded quartz. Sandstones of the arkosic facies are composed mainly of potassium feldspar, quartz, and felsic plutonic fragments. The source rocks of the Siegas Formation included mafic volcanic rocks (probably andesite), felsic plutonic rocks (possibly granitic), and quartzose sandstones.Facies, paleocurrents, and regional paleogeographic evidence indicate that the source area of the Siegas Formation was in northwestern New Brunswick, a region now covered by Devonian sedimentary rocks. The source area was probably an isolated, relatively discrete uplift similar to others previously described in northeastern Maine. It probably consisted of Cambrian or Ordovician quartzose sandstones like those of the Quebec Group of the Temiscouata area, overlain by middle Ordovician andesites like those of northeastern Maine, and intruded by a "granitic" body like the Rockabema Quartz Diorite of the Weeksboro – Lunksoos Lake anticlinorium in eastern Maine. The site of active erosion of this uplift probably was shifted to the northwest in the late Llandovery, possibly accompanied by the development of local mafic volcanism.

First Middle Ordovician ostracods from western Avalonia: paleogeographical and paleoenvironmental significance

2013 ◽  
Vol 87 (2) ◽  
pp. 269-276 ◽  
Author(s):  
Ed Landing ◽  
Mohibullah Mohibullah ◽  
Mark Williams
Keyword(s):  
New Species ◽  
New Brunswick ◽  
Early Cambrian ◽  
Marine Fauna ◽  
Cool Water ◽  
Middle Ordovician ◽  
Two New Species ◽  
Low Diversity ◽  
Near Shore ◽  
North Gondwana

Two new species of ostracods, Conchoprimitia cassidula n. sp. and Sorornanopsis avalonensis n. gen. n. sp., represent the first described Middle Ordovician ostracods from western Avalonia. They were recovered as phosphatized carapaces dissolved out of a late early Darriwilian (ca. 467 Ma) limestone boulder from the Triassic Lepreau Formation of New Brunswick, Canada. The ostracods form a low-diversity component of a higher energy, near-shore, shelf marine fauna dominated by the trilobites Neseuretus and Stapleyella and by the conodonts Drepanoistodus and Baltoniodus. The low diversity of this Avalonian ostracod fauna contrasts with more diverse (tens of species), coeval ostracod faunas from Laurentia and Baltica. The association of Darriwilian ostracods and trilobites from New Brunswick demonstrates continuing exchange of open marine, cool water biota between Avalonia, Baltica, and West and North Gondwana that began in the late early Cambrian.

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

scholarly journals Geochemistry and Mineralogy of Lower Paleozoic Heituao Shale from Tadong Low Uplift of Tarim Basin, China: Implication for Shale Gas Development

Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 635
Author(s):  
Shihu Zhao ◽  
Yanbin Wang ◽  
Yong Li ◽  
Honghui Li ◽  
Zhaohui Xu ◽  
...  
Keyword(s):  
Organic Matter ◽  
Tarim Basin ◽  
Shale Gas ◽  
Organic Matter Content ◽  
Matter Content ◽  
Mature Stage ◽  
Lower Paleozoic ◽  
Development Potential ◽  
Middle Ordovician ◽  
Average Value

Tarim Basin is the largest Petroliferous basin in China, while its shale gas development potential has not been fully revealed. The organic-rich black shale in middle Ordovician Heituao Formation from Tadong low uplift of Tarim Basin has been considered as an important source rock and has the characteristic of large thickness, high organic matter content and high thermal maturity degree. To obtain its development potential, geochemical, mineralogical and mechanics research is conducted based on Rock-Eval pyrolysis, total organic carbon (TOC), X-ray diffraction (XRD) and uniaxial compression experiments. The results show that: (1) the TOC content ranges between 0.63 and 2.51 wt% with an average value of 1.22 wt%, the Tmax values are 382–523 °C (average = 468.9 °C), and the S2 value is relatively low which ranges from 0.08 to 1.37 mg HC/g rock (averaging of 0.42 mg HC/g rock); (2) the organic matter of Heituao shale in Tadong low uplift show poor abundance as indicated by low S2 value, gas-prone property, and post mature stage (stage of dry gas). (3) Quartz is the main mineral component in Heituao shale samples, accounting for 26–94 wt% with an average of 72 wt%. Additionally, its Young’s modulus ranges from 20.0 to 23.1 GPa with an average of 21.2 GPa, Poisson’s ratio ranges between 0.11 and 0.21 (average = 0.15); (4) the fracability parameter of brittleness index (BI) ranges between 0.28 and 0.99 (averaging of 0.85), indicating good fracability potential of Heituao shale of Tadong low uplift and has the potential for shale gas development. This study reveals the shale gas accumulation potential in middle Ordovician of the Tarim Basin, and beneficial for future exploration and production practice.

Aldebarania arenitea, a new genus and species of Astropectinidae (Asteroidea; Echinodermata) from the Maastrichtian (Upper Cretaceous) Peedee Formation of North Carolina

1995 ◽  
Vol 69 (2) ◽  
pp. 376-380 ◽  
Author(s):  
Daniel B. Blake ◽  
Keith Sturgeon
Keyword(s):  
North Carolina ◽  
Shallow Water ◽  
Phylogenetic Relationships ◽  
Upper Cretaceous ◽  
New Genus ◽  
Water Environment ◽  
New Genus And Species ◽  
Marine Fauna ◽  
Shallow Water Environment

Aldebarania arenitea (Astropectinidae; Asteroidea; Echinodermata) is described from the Rocky Point Member of the Maastrichtian (Upper Cretaceous) Peedee Formation of North Carolina. A turbulent, shallow-water environment is suggested by sedimentary features, a diverse marine fauna, and the morphology of Aldebarania. Aldebarania appears to be a partial ecological equivalent of living Astropecten and Luidia; however, phylogenetic relationships within the Astropectinidae are unstudied and the origin of similarities is unknown.

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.

Age, chemistry, and tectonic setting of Miramichi terrane (Early Paleozoic) volcanic rocks, eastern and east-central Maine, USA

2021 ◽  
Vol 57 ◽  
pp. 239-273
Author(s):  
Allan Ludman ◽  
Christopher McFarlane ◽  
Amber T.H. Whittaker
Keyword(s):  
New Brunswick ◽  
Subduction Zone ◽  
Tectonic Setting ◽  
Volcanic Rocks ◽  
Calc Alkaline ◽  
East Central ◽  
Arc Volcanism ◽  
Middle Ordovician ◽  
Volcanic Suite ◽  
Back Arc

Volcanic rocks in the Miramichi inlier in Maine occur in two areas separated by the Bottle Lake plutonic complex: the Danforth segment (Stetson Mountain Formation) north of the complex and Greenfield segment to the south (Olamon Stream Formation). Both suites are dominantly pyroclastic, with abundant andesite, dacite, and rhyolite tuffs and subordinate lavas, breccias, and agglomerates. Rare basaltic tuffs and a small area of basaltic tuffs, agglomerates, and lavas are restricted to the Greenfield segment. U–Pb zircon geochronology dates Greenfield segment volcanism at ca. 469 Ma, the Floian–Dapingian boundary between the Lower and Middle Ordovician. Chemical analyses reveal a calc-alkaline suite erupted in a continental volcanic arc, either the Meductic or earliest Balmoral phase of Popelogan arc activity. The Maine Miramichi volcanic rocks are most likely correlative with the Meductic Group volcanic suite in west-central New Brunswick. Orogen-parallel lithologic and chemical variations from New Brunswick to east-central Maine may result from eruptions at different volcanic centers. The bimodal Poplar Mountain volcanic suite at the Maine–New Brunswick border is 10–20 myr younger than the Miramichi volcanic rocks and more likely an early phase of back-arc basin rifting than a late-stage Meductic phase event. Coeval calc-alkaline arc volcanism in the Miramichi, Weeksboro–Lunksoos Lake, and Munsungun Cambrian–Ordovician inliers in Maine is not consistent with tectonic models involving northwestward migration of arc volcanism. This >150 km span cannot be explained by a single east-facing subduction zone, suggesting more than one subduction zone/arc complex in the region.

Early-Middle Ordovician intermediate-mafic and ultramafic rocks in central Jilin Province, NE China: geochronology, origin, and tectonic implications

2019 ◽  
Vol 113 (3) ◽  
pp. 393-415 ◽  
Author(s):  
Zhigang Song ◽  
Chao Han ◽  
Hui Liu ◽  
Zuozhen Han ◽  
Junlei Yan ◽  
...  
Keyword(s):  
Jilin Province ◽  
Ultramafic Rocks ◽  
Ne China ◽  
Middle Ordovician ◽  
Tectonic Implications

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
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