Results 221 to 230 of about 66,668 (274)
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Geological Society, London, Memoirs, 1992
Abstract Since the publication of the Cambrian and Ordovician correlation charts by the Geological Society (Cowie et al. 1972; Williams et al. 1972) it has become more general practice to include the Tremadoc Series in the Ordovician, and although the precise level at which the base
R. E. Bevins +6 more
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Abstract Since the publication of the Cambrian and Ordovician correlation charts by the Geological Society (Cowie et al. 1972; Williams et al. 1972) it has become more general practice to include the Tremadoc Series in the Ordovician, and although the precise level at which the base
R. E. Bevins +6 more
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Geological Society, London, Special Publications, 2023
Abstract A comprehensive review of the current state of research on Kazakh Ordovician litho-, bio- and chronostratigraphy is presented. An Ordovician lithostratigraphic framework applied to eight Kazakh first-order tectonic units is outlined and its correlation with the International Chronostratigraphic Scale is given. Presently used criteria
Leonid Popov +5 more
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Abstract A comprehensive review of the current state of research on Kazakh Ordovician litho-, bio- and chronostratigraphy is presented. An Ordovician lithostratigraphic framework applied to eight Kazakh first-order tectonic units is outlined and its correlation with the International Chronostratigraphic Scale is given. Presently used criteria
Leonid Popov +5 more
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A giant Ordovician anomalocaridid
Nature, 2011Anomalocaridids, giant lightly sclerotized invertebrate predators, occur in a number of exceptionally preserved early and middle Cambrian (542-501 million years ago) biotas and have come to symbolize the unfamiliar morphologies displayed by stem organisms in faunas of the Burgess Shale type.
Peter, Van Roy, Derek E G, Briggs
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1994
Abstract A number of new marine invertebrate faunas came into being in Ordovician times, and the generally rather monotonous features of the Cambrian biota were changed. Among the fauna were trilobites, graptolites, articulate brachiopods, nautiloids, and rugose and tabulate corals, which are of great significance in stratigraphical ...
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Abstract A number of new marine invertebrate faunas came into being in Ordovician times, and the generally rather monotonous features of the Cambrian biota were changed. Among the fauna were trilobites, graptolites, articulate brachiopods, nautiloids, and rugose and tabulate corals, which are of great significance in stratigraphical ...
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Geological Society, London, Special Publications, 1964
Summary Stratigraphical and palaeontological evidence for the location of the boundaries of the Ordovician System is examined and considered to be less important than historical priority, so that the Tremadoc is excluded from the system.
H. B. Whittington, A. Williams
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Summary Stratigraphical and palaeontological evidence for the location of the boundaries of the Ordovician System is examined and considered to be less important than historical priority, so that the Tremadoc is excluded from the system.
H. B. Whittington, A. Williams
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Geological Magazine, 1945
Notes that an Ordovician trilobite from Tourmakeady, Ireland, previously doubtfully assigned to the genus Cybelopsis may be confidently placed in Loganopeltis according to recent evidence.
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Notes that an Ordovician trilobite from Tourmakeady, Ireland, previously doubtfully assigned to the genus Cybelopsis may be confidently placed in Loganopeltis according to recent evidence.
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American Midland Naturalist, 1945
In 1936 Bradford Willard and the late Professor Freeman Ward collected graptolites from a dump at the Hess slate quarry number 22, at Lynnport, Lehigh County, Pennsylvania (1). The material was submitted to Dr. Rudolf Ruedemann for identification. Dr. Ruedemann noted certain arthropods among the graptolites and kindly consented to study the specimens ...
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In 1936 Bradford Willard and the late Professor Freeman Ward collected graptolites from a dump at the Hess slate quarry number 22, at Lynnport, Lehigh County, Pennsylvania (1). The material was submitted to Dr. Rudolf Ruedemann for identification. Dr. Ruedemann noted certain arthropods among the graptolites and kindly consented to study the specimens ...
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1993
Abstract Most Ordovician and Silurian rocks in western and northwestern Canada were deposited on the North American craton and its western continental margin. Strata of these ages have also been recognized in three allochthonous terranes in the Cordillera, described in the companion volume on the Cordilleran Orogen (Gabrielse and Yorath,
M.P. Cecile, B.S. Norford
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Abstract Most Ordovician and Silurian rocks in western and northwestern Canada were deposited on the North American craton and its western continental margin. Strata of these ages have also been recognized in three allochthonous terranes in the Cordillera, described in the companion volume on the Cordilleran Orogen (Gabrielse and Yorath,
M.P. Cecile, B.S. Norford
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Biological Reviews, 1943
Summary Volborthella and Salterella of the Lower Cambrian arc probably pteropods, rather than cephalopods. The oldest undoubted cephalopods are two species of Plectronoceras from the Upper Cambrian of eastern Asia; both are small curved brevicones with ellipochoanitic siphuncles.
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Summary Volborthella and Salterella of the Lower Cambrian arc probably pteropods, rather than cephalopods. The oldest undoubted cephalopods are two species of Plectronoceras from the Upper Cambrian of eastern Asia; both are small curved brevicones with ellipochoanitic siphuncles.
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