Scientific Reports, 2022 The Early Ordovician is a key interval for our understanding of the evolution of life on Earth as it lays at the transition between the Cambrian Explosion and the Ordovician Radiation and because the fossil record of the late Cambrian is scarce.
Farid Saleh +12 more
doaj +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
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
openaire +5 more sources
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
core +1 more source
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
New contributions to the Ordovician biostratigraphy of the Western Precordillera, Argentina [PDF]
Estonian Journal of Earth Sciences, 2023 Upper Ordovician graptolites and conodonts are recorded from the Yerba Loca Formation in two sections, in the El Toro and Las Viudas creeks, from the El Tigre Range in the Western Precordillera of San Juan Province, Argentina. A collection of graptolites
Fernando E. Lopez +3 more
doaj +1 more source
Integration of Darriwilian (Middle Ordovician) δ13Corg chemostratigraphy with graptolite biostratigraphy in the classical Röstånga area in northwestern Scania (southern Sweden) [PDF]
Estonian Journal of Earth Sciences, 2020 The largely covered Middle Ordovician succession in the classic geological Röstånga area in northwestern Scania has not been studied for some 80 years.
Stig M. Bergström +4 more
doaj +1 more source
The cephalopods of the Boda Limestone, Late Ordovician, of Dalarna, Sweden [PDF]
, 2013 The late Katian, Late Ordovician Boda Limestone of Dalarna, Sweden contains a rich cephalopod assemblage. The assemblage consists of 61 species, in 31 genera, comprising almost all major Ordovician cephalopod orders.
Kröger, Björn +3 more
core +1 more source
Shiyou shiyan dizhi, 2023 Shale lithofacies has an important influence on shale reservoirs. It controls the hydrocarbon generation capacity, storage performance and fracturing performance of shale to a certain extent.
Guanbao REN +3 more
doaj +1 more source
The Upper Ordovician of Estonia: facies, sequences, and basin development [PDF]
Estonian Journal of Earth SciencesSequence stratigraphic analysis of the NabalaâPorkuni regional stages (RSs; upper KatianâHirnantian) of Estonia clarifies the Late Ordovician evolution of the Estonian ShelfâLivonian Basin.
Mark T. Harris +7 more
doaj +1 more source