Results 41 to 50 of about 1,764 (217)

The climatic significance of Late Ordovician-early Silurian black [PDF]

, 2017
The Ordovician-Silurian transition (455-430 Ma) is characterized by repeated climatic perturbations, concomitant with major changes in the global oceanic redox state best exemplified by the periodic deposition of black shales.
A. Pohl, Adcroft, Adcroft, Algeo, Algeo, Anderson, Armstrong, Armstrong, Armstrong, Arthur, Aumont, Barton, Beaulieu, Bergman, Berner, Berner, Berry, Bickert, Brenchley, Brenchley, Brenchley, Brunetti, Bryant, Came, Chaloner, Cocks, Cocks, Cocks, Cocks, Cramer, Cramer, Cramer, D. Ferreira, Denis, Donnadieu, Dutkiewicz, Edwards, Ekman, Enderton, Falkowski, Ferreira, Ferreira, Finlay, Finnegan, Finney, Follows, Friis, Friis, G. Le Hir, Ganopolski, Garcia, Gent, Ghienne, Gille, Girard, Hammarlund, Haq, Harper, Harper, Heckman, Herrmann, Herrmann, Hoffman, Jenkyns, Jeppsson, Johnson, Jones, Kageyama, Kaljo, Kemp, Kemp, Kump, LaPorte, Large, Laskar, Le Heron, Le Heron, Le Heron, Le Heron, Le Hir, Lenton, Lenton, Litchman, Loi, Long, Loydell, Loydell, Lunt, Luo, Marshall, Marshall, Marshall, Marshall, Marshall, Martin, McKinley, Meinhold, Melchin, Molteni, Monteiro, Montenegro, Moreau, Munnecke, Myhre, Nardin, Och, Osen, Owens, Page, Palastanga, Pohl, Pohl, Pohl, Porada, Poulsen, Poussart, Prange, R Core Team, Rahmstorf, Rasmussen, Redi, Roche, Roche, Rose, Rubinstein, Ruttenberg, Sageman, Schlanger, Schmidt, Servais, Servais, Sheehan, Steemans, Stommel, Stouffer, Sutcliffe, Torsvik, Trabucho-Alexandre, Trotter, Trotter, Tukey, Van Cappellen, Vandenbroucke, Vecoli, Walker, Wallmann, Webby, Winton, Y. Donnadieu, Yamanaka, Yan, Young, Zhang, Zhou, Zhuravlev   +154 more
core   +4 more sources

Pecularities of composition, structure and environments of Hirnantian deposits in the Timan-northern Ural sedimentary basin

Литосфера, 2018
The results of lithological and geochemical study of the Hirnantian deposits on the western slope of the Subpolar (Ko-BKB and Ko-108/01 sections) and Northern (BK-2 section) Urals are presented.
Anna I. Antoshkina, Lyubov’ A. Shmeleva   +1 more
doaj   +1 more source

Detrital-zircon geochronology and provenance of the Ocloyic synorogenic clastic wedge, and Ordovician accretion of the Argentine Precordillera terrane [PDF]

, 2015
The Precordillera terrane in northwestern Argentina is interpreted to be anexotic (Laurentian) continental fragment that was accreted to western Gondwanaduring the Ordovician. One prominent manifestation of the subductionand collision process is a Middle?
Astini, Ricardo Alfredo, McClelland, William C., Mueller, Paul A., Thomas, William A.   +3 more
core   +1 more source

Middle–Late Ordovician organic- walled phytoplankton from Sweden: diversity and early radiation [PDF]

Estonian Journal of Earth Sciences, 2023
The Borenshult-1 core, drilled in the vicinity of Motala, east of Lake Vättern in south central Sweden, comprises a well-dated and nearly complete succession of marine marly carbonates deposited relatively close to land. The 34 core samples analyzed for
Claudia V. Rubinstein, Vivi Vajda
doaj   +1 more source

Hirnantian (latest Ordovician) bio- and chemostratigraphy of the Stirnas-18 core, western Latvia [PDF]

Estonian Journal of Earth Sciences, 2010
Integrated study of the uppermost Ordovician Porkuni Stage in the Stirnas-18 core, western Latvia, has revealed one of the most complete Hirnantian successions in the eastern Baltic region.
Hints, Linda, Hints, Olle, Kaljo, Dimitri, Kiipli, Tarmo, Männik, Peep, Nõlvak, Jaak, Pärnaste, Helje   +6 more
doaj  

Trans-Atlantic application of the Baltic Middle and Upper Ordovician carbon isotope zonation [PDF]

Estonian Journal of Earth Sciences, 2015
Application of the recently introduced Baltic d13C isotope zonation to a composite North American Darriwilian through Hirnantian succession shows that in most intervals there is good trans-Atlantic agreement not only between the isotope zones but also ...
Stig M. Bergström, Matthew R. Saltzman, Stephen A. Leslie, Annalisa Ferretti, Seth A. Young   +4 more
doaj   +1 more source

Chronostratigraphy and geochronology: a proposed realignment [PDF]

, 2013
We propose a realignment of the terms geochronology and chronostratigraphy that brings them broadly into line with current use, while simultaneously resolving the debate over whether the Geological Time Scale should have a “single” or “dual” hierarchy of
Cita, Maria Bianca, Hilgen, Frits, Pratt, Brian R., Strasser, André, Thierry, Jacques, Weissert, Helmut, Zalasiewicz, Jan   +6 more
core   +1 more source

Hirnantia sagittifera (Brachiopoda) and Mucronaspis mucronata s.l. (Trilobita) in the Upper Ordovician of the East Baltic: taxonomy and distribution [PDF]

Estonian Journal of Earth Sciences, 2012
The brachiopod Hirnantia sagittifera (M’Coy) and trilobite morphs of the genus Mucronaspis from the topmost Ordovician Porkuni Stage of the central East Baltic are described and compared with those from the Hirnantian Stage of other regions.
Linda Hints, Helje Pärnaste, Lilita-Ilga Gailite†   +2 more
doaj   +1 more source

Dynamic sulfur and carbon cycles related to microbial sulfate reduction and volcanic activity during the Hirnantian glaciation in the Upper Yangtze Basin, South China

Frontiers in Earth Science, 2022
Parallel positive excursions of organic carbon (δ13Corg) and pyrite sulfur (δ34Spy) isotopes occurred globally during the Hirnantian glacial period. However, the reasons for these isotope excursions and their relationship with paleoenvironmental dynamics
Zaitian Dong, Zetang Wang, Wenli Zhang, Fei Zhao, Yunhang Du, Yuxuan Zhu, Xuehai Fu, Chaoyong Wang   +7 more
doaj   +1 more source

Late Ordovician (post–Sardic) rifting branches in the North Gondwanan Montagne Noire and Mouthoumet massifs of southern France [PDF]

, 2015
Upper Ordovician–Lower Devonian rocks of the Cabrières klippes (southern Montagne Noire) and the Mouthoumet massif in southern France rest paraconformably or with angular discordance on Cambrian–Lower Ordovician strata.
Colmenar, Jorge, Monceret, Eric, Pouclet, André, Vizcaïno, Daniel, Álvaro-Blasco, José Javier   +4 more
core   +1 more source