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Cambrian–Ordovician orogenesis in Himalayan equatorial Gondwana
, 2016An early Paleozoic tectonic event, the Kurgiakh orogeny, has long been known from the western Tethyan Himalaya, and it is conspicuously recorded by an angular unconformity between Cambrian marine shelf deposits and coarse Ordovician conglomerate, as well
A. Konon +25 more
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Diversification of bivalvesin the Ordovician
Geobios, 1999Abstract The Ordovician was the most significant Period in bivalve diversification. From a small Cambrianstock of palaeotaxodonts, the most fundamental radiation occurred in the early Ordovician. An intrinsic factor was the most significant, involving the evolution of the feeding gill within the palaeotaxodonts.
John C. W. Cope, Claude Babin
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Ordovician volcanism in Snowdonia
Geology Today, 1991During the Lower Palaeozoic, Wales was the site of a basin in which marine sediments, muds, silts and sands accumulated. The basin lay on the edge of a continental plate on the south-eastern side of the Iapetus ocean. In Ordovician times intense volcanic activity, related to the south-eastern subduction of the oceanic plate, shifted temporally and ...
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Biogeography of Ordovician sponges
Journal of Paleontology, 1999Sponges have an unrealized potential importance in biogeographic analysis. Biogeographic patterns determined from our analysis of all published data on distribution of Ordovician genera indicate Early Ordovician sponge faunas have relatively low diversity and are completely dominated by demosponges.
J. Keith Rigby, Marcelo G. Carrera
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Late Ordovician Reefs and the Biological Crisis at the Ordovician–Silurian Boundary
Stratigraphy and Geological Correlation, 2018Reef formation in the Late Ordovician was relatively widespread in the Sandbian and Katian times. In the late Katian, it gradually reduced and ended in the Hirnantian, before the end of the Ordovician. In parallel, reef-building skeleton frame-building biota disappeared and was replaced with algae and calcimicrobes.
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Biogeography of Ordovician stromatoporoids
Palaeogeography, Palaeoclimatology, Palaeoecology, 1980Abstract This paper reviews the distribution of stromatoporoids in relation to Ordovician geography. The labechiids were the first of the three Ordovician families to make their appearance. They became established in well-circulated, shallow, subtidal, equatorial waters of the open shelf during the Late Llanvirn-Llandeilo (North American Chazyan ...
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, 2015
Recurrent mass extinction events (at “biomere”—a biostratigraphic unit—boundaries) characterize the middle Cambrian to Early Ordovician (Tremadocian) time interval that is between the major Cambrian and Ordovician radiations of animal life.
M. Saltzman +3 more
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Recurrent mass extinction events (at “biomere”—a biostratigraphic unit—boundaries) characterize the middle Cambrian to Early Ordovician (Tremadocian) time interval that is between the major Cambrian and Ordovician radiations of animal life.
M. Saltzman +3 more
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American Journal of Science, 1935 , 2015
Cambrian–Ordovician strata of the North China block, one of China’s main tectonic provinces, are a thick (up to 1800 m) succession of mixed carbonate and siliciclastic sedimentary rocks. Sedimentological, biostratigraphic, and chemostratigraphic analysis
P. Myrow +7 more
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Cambrian–Ordovician strata of the North China block, one of China’s main tectonic provinces, are a thick (up to 1800 m) succession of mixed carbonate and siliciclastic sedimentary rocks. Sedimentological, biostratigraphic, and chemostratigraphic analysis
P. Myrow +7 more
semanticscholar +1 more source