Results 71 to 80 of about 1,166 (193)

Mercury Deposition in South China Across the Ordovician‐Silurian Transition: Implications for Climate Change

Geochemistry, Geophysics, Geosystems, Volume 26, Issue 7, July 2025.
Abstract Most of the global climate changes are closely associated with volcanic activity. However, the link between global cooling during the Ordovician‐Silurian (O‐S) transition and volcanism remains unclear due to limited constraints on large volcanic events before, during, and after the peak of the Hirnantian glaciation (PHG). Here, we present high‐
Weiliang Kong, Zhen Qiu, Jiaqiang Zhang, Wen Liu, Qin Zhang   +4 more
wiley   +1 more source

δ13C chemostratigraphy of the Middle and Upper Ordovician succession in the Tartu-453 drillcore, southern Estonia, and the significance of the HICE [PDF]

Estonian Journal of Earth Sciences, 2014
The δ13C isotope data from the Tartu-453 core section in southern Estonia enabled creation of a continuous Ordovician carbon isotope record, ranging from the Floian to the end of the Hirnantian.
Heikki Bauert, Leho Ainsaar, Kairi Põldsaar, Siim Sepp   +3 more
doaj   +1 more source

A new euarthropod from the Soom Shale (Ordovician) Konservat‐Lagerstätte, South Africa, with exceptional preservation of the connective endoskeleton and myoanatomy

Papers in Palaeontology, Volume 11, Issue 2, March/April 2025.
Abstract A new exceptionally preserved euarthropod, Keurbos susanae gen. et sp. nov. from the Upper Ordovician Soom Shale Konservat‐Lagerstätte of South Africa, is described herein. Two specimens exhibit an unusual preservation style such that the cuticular exoskeleton is preserved in low relief but retains high‐fidelity details, whereas the internal ...
Sarah E. Gabbott, Gregory D. Edgecombe, Johannes N. Theron, Richard J. Aldridge   +3 more
wiley   +1 more source

Late Ordovician ironstone and its relation to ocean redox instability, climate and glaciation

Sedimentology, Volume 72, Issue 2, Page 631-665, February 2025.
Abstract The Upper Ordovician (Katian) Neda Formation, a phosphatic ironstone, records a widespread but short‐lived shift to ferruginous waters across a vast epicontinental area. Lithofacies and stratigraphic reappraisal indicate that Neda ironstone deposition occurred on a storm‐dominated ramp when coastal upwelling emplaced eutrophic ferruginous ...
Edward J. Matheson, Jackson D. Malone, Peir K. Pufahl, Eric E. Hiatt   +3 more
wiley   +1 more source

New data on acritarchs from the Upper Ordovician of the Tungus basin, Siberian Platform [PDF]

Estonian Journal of Earth Sciences, 2014
Distinctive late Ordovician acritarch assemblages have been discovered for the first time from about a 100 m sedimentary succession exposed along the Bol¢shaya Nirunda River in Siberia.
Elena Raevskaya, Andrei Dronov
doaj   +1 more source

An Ordovician Assemblage of Cool Water‐Adapted Paleotropical Ostracods Suggests an Early Psychrosphere

Island Arc, Volume 34, Issue 1, January/December 2025.
ABSTRACT An ostracod assemblage from the Late Ordovician (Katian) Phu Ngu Formation of northern Vietnam, South China paleoplate, yields typical Baltic and Laurentian‐affinity genera together with some endemic forms. Detailed paleontological and sedimentary analysis of the Phu Ngu Formation suggests it was deposited in a deeper marine forearc setting ...
Anna McGairy, Phong Duc Nguyen, Mark Williams, Christopher P. Stocker, Thomas H. P. Harvey, Toshifumi Komatsu, Thomas W. Wong Hearing, C. Giles Miller, Chloé M. Marcilly, Alexandre Pohl   +9 more
wiley   +1 more source

Solid Earth Carbon Degassing and Sequestration Since 1 Billion Years Ago

Geochemistry, Geophysics, Geosystems, Volume 25, Issue 11, November 2024.
Abstract Solid Earth CO2 outgassing, driven by plate tectonic processes, is a key driver of carbon cycle models. However, the magnitudes and variations in outgassing are poorly constrained in deep‐time. We assess plate tectonic carbon emissions and sequestration by coupling a plate tectonic model with reconstructions of oceanic plate carbon reservoirs ...
R. Dietmar Müller, Adriana Dutkiewicz, Sabin Zahirovic, Andrew S. Merdith, Christopher R. Scotese, Benjamin J. W. Mills, Lauren Ilano, Ben Mather   +7 more
wiley   +1 more source

Composition and significance of the Katian (Upper Ordovician) conodont fauna of the Vaux Limestone (‘Calcaire des Vaux’) in Normandy, France [PDF]

Estonian Journal of Earth Sciences, 2014
Study of new conodont collections from the Vaux Limestone exposed at its classical locality at Saint-Hilaire-la-Gérard in the Sées syncline, the conodont fauna of which was previously described in a preliminary way by Weyant et al.
Annalisa Ferretti, Andrea Messori, Stig M. Bergström   +2 more
doaj   +1 more source

An Edgewood-type Hirnantian fauna from the Mackenzie Mountains, northwestern margin of Laurentia [PDF]

Silicified brachiopods from Hirnantian strata in three sections of the lower Whittaker Formation, Mackenzie Mountains, northwestern Canada, yielded a moderately diverse, Edgewood-type Hirnantian fauna, consisting of 13 species: Biparetis paucirugosus ...
Jin, Jisuo, Harper, David A.T.
core   +1 more source

The Upper Ordovician of Estonia: facies, sequences, and basin development [PDF]

Estonian Journal of Earth Sciences
Sequence stratigraphic analysis of the Nabala–Porkuni regional stages (RSs; upper Katian–Hirnantian) of Estonia clarifies the Late Ordovician evolution of the Estonian Shelf–Livonian Basin.
Mark T. Harris, Leho Ainsaar, Linda Hints, Peep Männik, Tõnu Meidla, Jaak Nõlvak, Tory Schultz, Peter M. Sheehan   +7 more
doaj   +1 more source