Gold in biogenic apatites of the Baltic-Ladoga phosphorite basin
Записки Горного института, 2022 The distribution of gold in biogenic apatites from the Ordovician deposits in the northwest of the East European Platform shows that the maximum concentration of gold in apatites is found within the Ladoga-Baltic suture zone.
Sergey B. Felitsyn, Nadezhda A. Alfimova
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Upper Ordovician hardgrounds – from localized surfaces to global biogeochemical events [PDF]
Estonian Journal of Earth Sciences, 2023 Upper Ordovician hardgrounds display a spectrum of complexity reflecting a range of local to global-scale processes. Hardgrounds are cemented seafloor surfaces typically marked by the presence of encrusting taxa and borings.
Timothy R. Paton +4 more
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The Ordovician of Sardinia (Italy): from the ‘Sardic Phase’ to the end-Ordovician glaciation, palaeogeography and geodynamic context [PDF]
, 2022 This review illustrates the most important features of the Ordovician successions of the Sardinian basement. We focus on the stratigraphy and tectonic structures in the tectonic units of the External and Nappe zones of the Variscan basement.
Pillola G. L. +10 more
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Echinoderm Lagerstätten from high-latitude Gondwana – filling the gap in the Ordovician diversification of the phylum [PDF]
Estonian Journal of Earth Sciences, 2023 The phylum Echinodermata is a major component of marine ecosystems since the first appearance of echinoderms in the Cambrian. Like other metazoan phyla, echinoderms underwent two major evolutionary pulses in early Palaeozoic times: the Cambrian Explosion
Martina Nohejlová +4 more
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Changes in shelf phosphorus burial during the Hirnantian glaciation and its implications [PDF]
Estonian Journal of Earth Sciences, 2023 The Late Ordovician mass extinction occurred during an icehouse interval, accompanied by the glaciation of the supercontinent Gondwana, which was located at the South Pole at that time.
Johann Müller +4 more
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A Cambrian–Ordovician Terrestrialization of Arachnids [PDF]
Frontiers in Genetics, 2020 Understanding the temporal context of terrestrialization in chelicerates depends on whether terrestrial groups, the traditional Arachnida, have a single origin and whether or not horseshoe crabs are primitively or secondarily marine. Molecular dating on a phylogenomic tree that recovers arachnid monophyly, constrained by 27 rigorously vetted fossil ...
Jesus Lozano-Fernandez +8 more
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Oil and gas sources in Shunbei Oilfield, Tarim Basin
Shiyou shiyan dizhi, 2020 The hydrocarbon sources in the Middle and Lower Ordovician in the Shunbei area of the Tarim Basin were studied based on the geochemical characteristics of oil and gas samples.
Rong GU, Lu YUN, Xiuxiang ZHU, Meng ZHU
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Ordovician palaeogeography and climate change
, 2020 New palaeogeographical reconstructions for the earlier Ordovician (480 Ma), and later Ordovician (450 Ma) integrate revised longitude-calibrated palaeomagnetic reconstructions and the inclusion of synthetic plate margins within the now-vanished oceanic ...
L. Cocks, Trond H. Torsvik
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The Ordovician System: From overlapping unit stratotypes to Global Boundary Stratotype Sections and Points [PDF]
Estonian Journal of Earth Sciences, 2023 For nearly a century the Ordovician System was hidden as Murchison and Sedgwick tussled over the overlapping ground between their Silurian and Cambrian systems.
David A. T. Harper +2 more
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Early Tremadocian graptolites from the Arivechi area, Sonora, northern Mexico [PDF]
Estonian Journal of Earth Sciences, 2023 Graptolites from the early Tremadocian Anisograptus matanensis Biozone are identified from east-central Sonora, northwestern Mexico, within a carbonate-shelf succession deposited on the southwestern continental shelf margin of Laurentia.
Dulce Raquel Reyes-Montoya +5 more
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