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A global synthesis of the latest Ordovician Hirnantian brachiopod faunas
Transactions of the Royal Society of Edinburgh: Earth Sciences, 1988ABSTRACTA global review of new and existing data on the distribution of uppermost Ordovician (Hirnantian) brachiopods indicates the existence of at least three biogeographically distinct faunas. The typical Hirnantia fauna characterised subtropical and temperate latitudes and comprised a variety of ecological associations; the fauna reached its acme ...
Rong Jia-yu, David A. T. Harper
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Environmental changes in the Hirnantian (upper Ordovician) of the Prague Basin, Czechoslovakia
Geological Journal, 1989AbstractSedimentary sequences through the uppermost Ordovician (Hirnantian), Kosov Formation, are described. The Kosov Formation is a shale‐dominated formation with two thin horizons of sandy diamictites near the base and two ‘flysch’ units separated by shales forming the main part of the formation, which is overlain abruptly by Silurian graptolitic ...
P. J. Brenchley, P. Štorch
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Pre‐Hirnantian Ashgill climatically warm event in the Mediterranean region
Lethaia, 2003Compilation of the marine, benthic megafossils from approximately the mid-Ashgill of the Mediterranean region, including much of Central and Southern Europe plus North Africa, and elsewhere indicates a warm interval featuring bioclastic limestone and a warm climate marine fauna.
A.J Boucot +3 more
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Circular, Cryogenic Structures from the Hirnantian Deglaciation Sequence (Anti-Atlas, Morocco)
Journal of Sedimentary Research, 2013Abstract More than a hundred circular structures are observed at the topmost part of the Late Ordovician glaciogenic record in the central Anti-Atlas, southern Morocco. The structures were formed in the outer glaciated platform and characterize the Hirnantian deglaciation sequence.
Nutz, Alexis +2 more
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The Hirnantian glacial landsystem of the Sahara: a meltwater-dominated system
Geological Society, London, Memoirs, 2016During the Hirnantian (443 Ma), ice sheets expanded towards the present-day north over North Africa and the Arabian Peninsula when the western part of the Gondwana supercontinent straddled the South Pole. A glacigenic succession is exposed around the flanks of several Saharan cratonic basins, including Murzuq and Al Kufrah basins in Libya.
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The Hirnantian δ13C Positive Excursion in the Nabiullino Section (South Urals)
Doklady Earth Sciences, 2018The upper Sandbian, Katian, and Hirnantian complexes of conodonts in the upper Ordovician section of the western slope of the Southern Urals near the village of Nabiullino were studied. The δ13C positive excursion with a maximum of 3.3‰ associated with the global Hirnantian isotopic event, HICE, was fixed for the first time.
R. R. Yakupov +2 more
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Middle East Oil, Gas and Geosciences Show (MEOS GEO)
The Late Ordovician marked one of Earth's most profound climatic transitions, culminating in the Hirnantian glaciation and the second-largest mass extinction in the Phanerozoic (Finlay et al., 2010). Glacial advance during this stage extended as far as ∼30°S (Trotter et al., 2008; Phol et al., 2016; Cocks & Torsvik, 2021), sculpting widespread ...
Stefano Patruno +3 more
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The Late Ordovician marked one of Earth's most profound climatic transitions, culminating in the Hirnantian glaciation and the second-largest mass extinction in the Phanerozoic (Finlay et al., 2010). Glacial advance during this stage extended as far as ∼30°S (Trotter et al., 2008; Phol et al., 2016; Cocks & Torsvik, 2021), sculpting widespread ...
Stefano Patruno +3 more
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Late Hirnantian Clastic Depositional Systems Using Sequence Stratigraphy and Chronostratigraphy
Abu Dhabi International Petroleum Exhibition & Conference, 2018Abstract The Hoban and Baqaa Members are located between the glacial to early post-glacial Sarah Formation (Ordovician) and the Qalibah Formation (Silurian). They have been distinguished as separate stratigraphic units in few outcrops of northern Saudi Arabia based on palynological analyses, graptolites, shell fragments, and their ...
Saeed Alshahrani, Rainer Zuhlke
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Katian prelude to the Hirnantian (Late Ordovician) mass extinction: a Baltic perspective
Geological Journal, 2011AbstractThe diversity of several groups of Late Ordovician fossils in the Baltic is discussed and corresponding curves are presented. The curves are correlated with the latest δ13C trend and probable sea surface temperatures of the equatorial ocean in order to link biodiversity and environmental changes.
Dimitri Kaljo +5 more
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THE HIRNANTIAN ISOTOPE CARBON EXCURSION (HICE) IN SOUTHERN NORWAY
Geological Society of America Abstracts with Programs, 2017Mikael Calner +2 more
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