Results 31 to 40 of about 254 (156)
Ordovician Bryozoa of Estonia [PDF]
Estonian Journal of Earth Sciences, 2023 sessile colonial, filter-feeding animals, many of which possess hard carbonate skeletons of different morphology. The bryozoan faunas of the Ordovician of Estonia were studied early by famous naturalists such as Karl Eduard von Eichwald and WÅadisÅaw ...
Andrej Ernst
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Литосфера, 2018 The results of lithological and geochemical study of the Hirnantian deposits on the western slope of the Subpolar (Ko-BKB and Ko-108/01 sections) and Northern (BK-2 section) Urals are presented.
Anna I. Antoshkina +1 more
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EVENT STRATIGRAPHY AND CORRELATION PROBLEMS OF THE ORDOVICIAN STRATA OF GORNY ALTAI AND SALAIR
Геодинамика и тектонофизика, 2021 Study of the Ordovician sedimentary sequences of Gorny Altai and Salair has revealed lithological and paleontological features correlating with global sedimentary events:(1) The Acerocare Regressive Event (an initial event in the Early Tremadocian);(2 ...
N. V. Sennikov +5 more
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Middle–Late Ordovician organic- walled phytoplankton from Sweden: diversity and early radiation [PDF]
Estonian Journal of Earth Sciences, 2023 The Borenshult-1 core, drilled in the vicinity of Motala, east of Lake Vättern in south central Sweden, comprises a well-dated and nearly complete succession of marine marly carbonates deposited relatively close to land. The 34 core samples analyzed for
Claudia V. Rubinstein, Vivi Vajda
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An earth system approach to understanding the end-Ordovician (Hirnantian) mass extinction [PDF]
, 2014 The Hirnantian mass extinction is recognized as the first of the "big three" extinctions and, along with the end-Permian and end-Cretaceous events, is the result of an acceleration in biotic extinctions concomitant with a rise in originations. The Hirnantian mass extinction is characterized by high taxonomic impact and within-community extinctions ...
Armstrong, H. A., Harper, D.A.T.
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Hirnantia sagittifera (Brachiopoda) and Mucronaspis mucronata s.l. (Trilobita) in the Upper Ordovician of the East Baltic: taxonomy and distribution [PDF]
Estonian Journal of Earth Sciences, 2012 The brachiopod Hirnantia sagittifera (M’Coy) and trilobite morphs of the genus Mucronaspis from the topmost Ordovician Porkuni Stage of the central East Baltic are described and compared with those from the Hirnantian Stage of other regions.
Linda Hints +2 more
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Late Ordovician (Hirnantian) shelly fossils from New Zealand and their significance [PDF]
New Zealand Journal of Geology and Geophysics, 2004 Abstract A poorly preserved fauna of brachiopods, trilobites, corals, molluscs, bryozoans, echinoderms, and ostracods is described from Wangapeka Valley, northwest South Island. It can be dated to the latest Ordovician Hirnantian Stage, equivalent to Bolindian Bo4‐Bo5, by immediately underlying graptolite faunas and also by some of its contained shelly
L. R. M. Cocks, Roger A. Cooper
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Trans-Atlantic application of the Baltic Middle and Upper Ordovician carbon isotope zonation [PDF]
Estonian Journal of Earth Sciences, 2015 Application of the recently introduced Baltic d13C isotope zonation to a composite North American Darriwilian through Hirnantian succession shows that in most intervals there is good trans-Atlantic agreement not only between the isotope zones but also ...
Stig M. Bergström +4 more
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Frontiers in Earth Science, 2022 Parallel positive excursions of organic carbon (δ13Corg) and pyrite sulfur (δ34Spy) isotopes occurred globally during the Hirnantian glacial period. However, the reasons for these isotope excursions and their relationship with paleoenvironmental dynamics
Zaitian Dong +7 more
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The Checa Silurian Section, an Outstanding Fossil Site in the Molina-Alto Tajo UNESCO Global Geopark, Spain [PDF]
Geoconservation Research, 2021 The Paleozoic succession in the Nevera inlier of the Molina-Alto Tajo UNESCO Global Geopark (Western Iberian Cordillera, NE Spain) includes an incomplete, richly fossiliferous Silurian succession, ca. 350‒400 m thick, at the locality of Checa, one of the
Juan Carlos Gutierrez-Marco, Petr Storch
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