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Ordovician Volcanism in the Puna
2020The orogenic evolution of the Famatinian Cycle in the Puna began during the Upper Cambrian–Lower Tremadocian with records of volcanism conforming two sub-meridian magmatic belts. The Western Magmatic Belt in the Lower Tremadoc is represented by dacitic to rhyolitic lavas, hyaloclastites, tuffs and pyroclastic flows, and basaltic lavas associated with ...
Clara Eugenia Cisterna +1 more
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Biogeography of Ordovician bryozoans
Palaeogeography, Palaeoclimatology, Palaeoecology, 1990Abstract The following biogeographic patterns have been determined from a quantitative analysis of the global distribution of the Ordovician genera: Arenig faunas are of low diversity, with provinces appearing in North America and Baltica. Three provinces appear in the Llanvirn: a Baltic Province, a North American Province and a Siberian Province ...
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Correlation by Ordovician Bentonite
The Journal of Geology, 1932It is postulated that the Ordovician bentonite beds of Eastern North America were derived from numerous local, rather than one centrally located volcano. Six criteria, which should be considered in any attempt to correlate bentonite beds, are given. In central Pennsylvania a correlation has been established between the bentonite beds over an area which
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A Thai Ordovician receptaculitalean
Alcheringa: An Australasian Journal of Palaeontology, 1989Fragmentary silicified receptaculitalean material from the Early-Middle Ordovician (Ibexian-Whiterockian) Tha Manao Formation at Khao Tham, west-central Thailand, is described as ?Fisherites sp. This is one of the few southeast Asian records of the order.
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Ordovician Correlations in Oklahoma
AAPG Bulletin, 1927The following correlations are made: The Viola ("white") lime of the oil fields, with the uppermost limestone in contact with the Chattanooga shale near Tahlequah, and with the upper part of the Viola limestone in the Arbuckle Mountains. The "post-Wilcox" well cuttings, with the Bromide formation in the mountains, and with the Tyner sediments between ...
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Oxygenation as a driver of the Great Ordovician Biodiversification Event
Nature Geoscience, 2017C. Edwards +3 more
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Ordovician integrative stratigraphy and timescale of China
Science China. Earth Sciences, 2018Yuandong Zhang +7 more
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