Results 81 to 90 of about 1,800 (206)

Reconstructing a Super-Eruption From the Upper Ordovician Period in the Eastern Pyrenees, Spain [PDF]

Lithosphere
The Pyrenean basement rocks, NE of the Iberian Peninsula, southwestern Europe, include evidence of several pre-Variscan magmatic episodes which indicate the complex geodynamic history of this segment of the northern Gondwana margin from late ...
Joan Marti, Josep M. Casas, Josep A. Muñoz   +2 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

Lower–Middle Ordovician brachiopods from the Eastern Cordillera of Peru: evidence of active faunal dispersal across Rheic and Iapetus oceans

Papers in Palaeontology, Volume 10, Issue 5, September/October 2024.
Abstract New Floian and early middle Darriwilian brachiopod assemblages of the San José Formation of the Eastern Cordillera of Peru are presented. A new genus and species, Apurimella santiagoi, and two new species, Phragmorthis henrylunae and Nocturnellia ashaninka, are described.
Jorge Colmenar, César Augusto Chacaltana, Juan Carlos Gutiérrez‐Marco   +2 more
wiley   +1 more source

Alleged cnidarian Sphenothallus in the Late Ordovician of Baltica, its mineral composition and microstructure [PDF]

Acta Palaeontologica Polonica, 2015
Sphenothallus is a problematic fossil with possible cnidarian affinities. Two species of Sphenothallus, S. aff. longissimus and S. kukersianus, occur in the normal marine sediments of the Late Ordovician of Estonia. S.
Olev Vinn, Kalle Kirsimäe
doaj   +1 more source

Late Ordovician (Katian) spores in Sweden: oldest land plant remains from Baltica

GFF, 2014
A palynological study of the Ordovician–Silurian boundary (Katian–Rhuddanian) succession in the Rostanga-1 drillcore, southern Sweden, has been performed. The lithology is dominated by mudstone and graptolitic shale, with subordinate limestone, formed in the deeper marine halo of southern Baltica.
BADAWY, AHMED SALAH, Mehlqvist, Kristina, Vajda, Vivi, Ahlberg, Per, Calner, Mikael   +4 more
openaire   +3 more sources

Paradox lost: wide gape in the Ordovician brachiopod Rafinesquina explains how unattached filter‐feeding strophomenoids thrived on muddy substrates

Palaeontology, Volume 67, Issue 2, March/April 2024.
Abstract Strophomenoid brachiopods had thin, concavo‐convex shells, were ubiquitous colonizers of Palaeozoic muddy seafloors, and are hypothesized to have filter‐fed in a concave‐upward orientation. This orientation would elevate their line of commissure out of potentially lethal lophophore‐clogging mud.
Benjamin F. Dattilo, Rebecca L. Freeman, Kyle Hartshorn, David Peterman, Aaron Morse, David L. Meyer, Lindsay G. Dougan, James W. Hagadorn   +7 more
wiley   +1 more source

A modern assessment of Ordovician chitinozoans from the Shelve and Caradoc areas, Shropshire, and their significance for correlation [PDF]

, 2009
New chitinozoan data are presented from the classical section along the Onny River in the type Caradoc area, and from the deeper-water sections in the Shelve area, including the former British candidate GSSP for the base of the Upper Ordovician Series ...
Achab, ANTONIO ANCILLETTA, Bancroft, Bergström, Cave, Dean, Dean, Hurst, JACQUES VERNIERS, Jansonius, Jenkins, Lynas, Murchison, Nõlvak, Nõlvak, Nõlvak, Pocock, RICHARD A. FORTEY, Rushton, Savage, Strachan, THIJS R. A. VANDENBROUCKE, Turner, Whittard   +23 more
core   +2 more sources

Late Ordovician and early Silurian virgianid and stricklandioid brachiopods from North Greenland: implications for a warm‐water faunal province

Papers in Palaeontology, Volume 10, Issue 1, January/February 2024.
Abstract An unusually rich and diverse suite of virgianid brachiopods, hitherto poorly known, is systematically described here for the first time from the Ordovician–Silurian boundary interval (late Katian – Aeronian) of North Greenland. The Late Ordovician virgianids comprise typical taxa of the warm‐water Tcherskidium fauna (e.g.
Jisuo Jin, Christian M. Ø. Rasmussen, Peter M. Sheehan, David A. T. Harper   +3 more
wiley   +1 more source

Chitinozoan biozonation in the upper Katian and Hirnantian of the Welsh Basin, UK [PDF]

Review of Palaeobotany and Palynology, 2014
AbstractHere we present a chitinozoan biostratigraphical framework for the South Wales upper Katian and Hirnantian (Ashgill) succession. The current study indicates that three of the six Avalonian Ashgill chitinozoan biozones are recognised in the Welsh Basin; the bergstroemi, fossensis and umbilicata biozones.
Challands, Thomas J, Vandenbroucke, Thijs, Armstrong, Howard A, Davies, Jeremy R   +3 more
openaire   +1 more source

Orbital and Millennial‐Scale Cycles Through the Hirnantian (Late Ordovician) in Southern China

Geochemistry, Geophysics, Geosystems, Volume 25, Issue 1, January 2024.
Abstract The Hirnantian period, making the end of the Ordovician with significant mass extinctions and large ice‐sheets, is a critical interval for studying paleoclimate variations. This research represents the first cyclostratigraphic study of this period, utilizing high‐resolution (1 mm sampling rate) geochemical data from the ∼7‐m thick SH‐1 drill ...
Siding Jin, Haiyang Cao, Mingcai Hou, Jiawei Wang, Chao Ma, Yu Liu   +5 more
wiley   +1 more source