Results 41 to 50 of about 53,918 (269)
Systematics, morphology, and appendages of an Early Ordovician pilekiine trilobite Anacheirurus from Fezouata Shale and the early diversification of Cheiruridae [PDF]
Acta Palaeontologica Polonica, 2021 Pilekiines are the earliest diverging members of the successful trilobite family Cheiruridae. The pilekiine genus Anacheirurus is characterized by sub-quadratic to sub-oval glabella, pitted genae, and a distinct trunk with elongated pleural spines in ...
FRANCESC PÉREZ-PERIS +3 more
doaj +1 more source
On the Upper Ordovician unconformity in the Pyrenees : new evidence from the La Cerdanya area [PDF]
, 2007 In recent years, contradictory reports about whether or not an unconformity exists at the base of the Upper Ordovician succession of the Pyrenees have been made.
Fernández, Óscar +4 more
core +1 more source
Cascading trend of Early Paleozoic marine radiations paused by Late Ordovician extinctions
Proceedings of the National Academy of Sciences of the United States of America, 2019 Significance The first 120 million years of Phanerozoic life witnessed significant changes in biodiversity levels. Attempts to correlate these changes to potential short-term environmental drivers have been hampered by the crude temporal resolution of ...
C. Rasmussen +3 more
semanticscholar +1 more source
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
doaj +1 more source
Earth and Planetary Science Letters, 2019 Mercury (Hg) enrichment in stratigraphic successions is now widely used as a proxy for volcanic inputs, often for the purpose of documenting a relationship between large igneous province (LIP) magmatism and ecosystem perturbations.
Jun Shen +6 more
semanticscholar +1 more source
Metal enrichment in lithologically complex black shales: a case study from the Tremadocian of NE Estonia [PDF]
Estonian Journal of Earth Sciences, 2021 Significantly elevated U, Mo, Zn and Pb contents characterize the Early Ordovician black shales in the Sillamäe area, NE Estonia. The presence of silty interlayers with sulphidic mineralization and authigenic carbonates suggests unique physicochemical ...
Rutt Hints +4 more
doaj +1 more source
Ordovician and Silurian Formations of the Baltic Syneclise (NE Poland): An Organic Geochemistry Approach [PDF]
, 2022 The Baltic Syneclise is one of the Paleozoic basins along the western margin of the East European Craton. Commercial amounts of hydrocarbons have been found onshore and offshore in the Middle Cambrian sandstones and Upper Ordovician limestone reefs.
P. Kosakowski +2 more
core +1 more source
, 2020 Stratigraphic, palaeontologic, and palaeomagnetic data support a hypothesis that argues for the Argentine Precordillera rifting from the southwestern margin of Laurentia in low latitudes during the Cambrian, migrating across the Iapetus Ocean, colliding ...
G. Albanesi +4 more
semanticscholar +1 more source
Terrestrialization in the Ordovician
Geological Society, London, Special Publications, 2022 Abstract This contribution reviews the evidence for terrestrial organisms during the Ordovician (microbial, land plant, fungal, animal) and for the nature of the terrestrial biota. The evidence regarding the origin and early diversification of land plants combines information from both fossils and living organisms.
Wellman, Charles +2 more
openaire +4 more sources
A new species of the problematic organism Webbyites from the Early Ordovician Fezouata Biota of Morocco [PDF]
Estonian Journal of Earth Sciences, 2023 The problematic colonial organism Webbyites has previously been considered to be a hydroid (phylum Cnidaria). In this paper, we describe a new species, Webbyites felix sp. nov., from the Early Ordovician Fezouata Konservat-Lagerstätte of Morocco.
Lucy A. Muir +1 more
doaj +1 more source