Results 71 to 80 of about 1,784 (228)

Cyclocystoids (Echinodermata) from the Upper Ordovician (early Katian) Kirkfield and Verulam formations of Ontario, Canada: implications for cyclocystoid skeletal homologies, anatomy, functional morphology, life mode, and systematics

Journal of Paleontology
New discoveries prompt reinterpretations of one of the most enigmatic echinoderm classes, the Cyclocystoidea. Exceptionally well-preserved cyclocystoids have been discovered in the Upper Ordovician (Katian) Kirkfield and Verulam formations in the ...
D. Kolata, R. Mooi, T. Guensburg, Joseph M. Koniecki   +3 more
semanticscholar   +1 more source

Micro-CT analysis of Katian radiolarians from the Malongulli Formation, New South Wales, Australia, and implications for skeletogenesis

Journal of Paleontology, 2023
. A diverse and well-preserved radiolarian assemblage from the Malongulli Formation, New South Wales, Australia, contains 13 species representing 10 genera and six families.
Siyumini Perera, Jonathan C. Aitchison
semanticscholar   +1 more source

Lower Katian (Upper Ordovician) delta(13)C chemostratigraphy, global correlation and sea-level changes in Baltoscandia [PDF]

, 2011
A long-standing problem in the Ordovician stratigraphy of south-eastern Norway has been to the relations between the Mjosa Formation in the Lake Mjosa region and coeval strata in the Oslo region.
Bruton, David L., David L. Bruton, Bergstroem, Stig M., Birger Schmitz, Schmitz, Birger, Stig M. Bergström, Seth A. Young, Schmitz, Birger,, Lund University., Young, Seth A.   +9 more
core   +1 more source

Upper Katian (Upper Ordovician) trans-Atlantic δ13C chemostratigraphy : the geochronological equivalence of the ELKHORN and PAROVEJA excursions and its implications [PDF]

, 2020
Since 2010 when the North American ELKHORN and Baltoscandic PAROVEJA isotope excursions were first described and named, their mutual age relations have remained uncertain, if not controversial.
Kleffner, Mark, Eriksson, Mats E., Bergström, Stig M., Stig M. Bergström, Mark Kleffner, Mats E. Eriksson   +5 more
core   +1 more source

A new glyptorthid species (Brachiopoda: Orthida) from the Upper Ordovician of Estonia [PDF]

Estonian Journal of Earth Sciences, 2010
A new glyptorthid brachiopod species Bassettella alata with surface pits and lamellose frills is described from the Upper Ordovician Haljala and Keila stages of northern Estonia.
Linda Hints
doaj   +1 more source

New Zealand Geological Timescale 2025

New Zealand Journal of Geology and Geophysics, Volume 69, Issue 1, March 2026.
New Zealand Geological Timescale 2025 (NZGT 2025) is the first comprehensive update and revision of the New Zealand Geological Timescale in a decade. The criteria used to establish age ranges of New Zealand Stages within the NZGT have been reviewed, calibrated, and revised where required against the 2023/04 International Chronostratigraphic Chart and ...
Christopher D. Clowes, James S. Crampton, Kyle J. Bland, J. Ian Raine, Andrew F. Boyes, Hamish J. Campbell, Erica M. Crouch, Martin P. Crundwell, Neville Hudson, Elizabeth M. Kennedy, Donald A. B. MacFarlan, Hugh E. G. Morgans, Marcus D. Richards, Matthew W. Sagar   +13 more
wiley   +1 more source

[Retracted] The taphonomy of a trilobite fauna from an uppermost Katian echinoderm Lagerstätte in South West Wales [PDF]

, 2018
The uppermost Katian (Rawtheyan) Slade and Redhill Mudstone Formation, in the Llanddowror area of Carmarthenshire in South West Wales, contains an horizon yielding abundant, articulated crinoids, cystoids, mitrate ‘carpoids’, asteroids and ophiuroids ...
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core   +3 more sources

Enhanced Continental Weathering Triggered the Anoxia of Seawater and Mass Extinctions During the Late Ordovician

Journal of Marine Science and Engineering
During the Late Ordovician period, changes in climate and mass extinctions were observed; however, the factors influencing these phenomena have not been fully understood.
Pan Tang, Xiangrong Yang, Detian Yan
doaj   +1 more source

La femme fait la maison: The Accumulation of Surplus Value through Family Planning in Burkina Faso1

Antipode, Volume 58, Issue 1, January 2026.
Abstract Since the 1960s, demographers, international donors, and governments have calculated the political, economic, and social benefits of modern contraception usage in West Africa. We evidence how family planning technologies (FPTs) that are tethered to population development extract double value (productive and reproductive labour) from Burkinabè ...
T.D. Harper‐Shipman, Katian Napon
wiley   +1 more source

Carbonate mud mounds, conglomerates, and sea-level history in the Katian (Upper Ordovician) of central Sweden [PDF]

, 2010
The Katian (Upper Ordovician) facies succession of the Siljan district, central Sweden, records some of the most prominent environmental changes in the Ordovician of Baltoscandia. These changes include two separate phases of major sea-level drawdown that
Lehnert, Oliver, Calner, Mikael, Joachimski, Michael   +2 more
core   +1 more source