Results 11 to 20 of about 325 (174)
Givetian megaspore assemblages of the Mikhailovksy mine (Kursk oblast)
Известия высших учебных заведений: Геология и разведкаBackground. Disperse megaspores from the Givetian deposits of the Mikhailovsky mine, Kursk Oblast, were studied for the first time. Following chemical maceration of the samples, their selection and identification, 12 species belonging to 8 genera of ...
D. I. Marinina, O. A. Orlova
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The early diversification of ray-finned fishes (Actinopterygii): hypotheses, challenges and future prospects. [PDF]
Biol Rev Camb Philos Soc, 2023 ABSTRACT Actinopterygii makes up half of living vertebrate diversity, and study of fossil members during their Palaeozoic rise to dominance has a long history of descriptive work. Although research interest into Palaeozoic actinopterygians has increased in recent years, broader patterns of diversity and diversity dynamics remain critically understudied.
Henderson S +3 more
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Rise and fall of the phacopids: the morphological history of a successful trilobite family
Palaeontology, Volume 66, Issue 5, September/October 2023., 2023 Abstract Phacopidae were a successful family of the Silurian–Devonian period. Although their diversity trends are well identified, their shape evolution is unknown; their morphology often considered to be conservative. We have quantified these morphologies using geometric morphometrics (landmarks) and investigated their evolution using morphological ...
Valentin Bault +7 more
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Sedimentology, Volume 70, Issue 5, Page 1413-1471, August 2023., 2023 ABSTRACT The study examines bioclastic carbonate contourites that arise from the broad spectrum of bottom‐current related sedimentary processes ranging from deposition to erosion. The result of the intermittent accumulation of sediment are thin and condensed successions with abundant hiatuses.
Heiko Hüneke +9 more
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Crustal Imaging of Portugal Mainland Using Magnetotelluric Data
Earth and Space Science, Volume 10, Issue 7, July 2023., 2023 Abstract The comprehensive mapping of resistivities in depth and its interpretation is of great importance to unravel the electrical properties of deep‐seated rocks, providing significant insights into the structure of the crust. The first 3D resistivity model for Portugal mainland is here reported using data from 31 broadband MT soundings spaced 50 ...
P. Baltazar‐Soares +7 more
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Tectonics, Volume 42, Issue 7, July 2023., 2023 Abstract Rocks exposed along both sides of the Smith Sound in Ellesmere Island and NW Greenland record the tectono‐sedimentary evolution of the whole Phanerozoic, including two periods of mountain building—the Palaeozoic Ellesmerian Orogeny and the Palaeogene Eurekan Orogeny—and the formation of two major sedimentary basins, the Franklinian and the ...
Cornelia Spiegel +13 more
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Sedimentology, Volume 70, Issue 4, Page 1251-1280, June 2023., 2023 ABSTRACT During the Middle Devonian, reef growth reached an acme, and corals and stromatoporoids colonized depositional niches commonly considered unfavourable for reefal organisms. This paper documents the detailed facies architecture and palaeoecology of a stratigraphically thin (ca 12 m, ‘carpet reef’), lower Givetian reefal body exposed along the ...
Tanja Unger +6 more
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Известия высших учебных заведений: Геология и разведка, 2016 The stratigraphie distribution and systematic composition of the Middle-Upper Devonian remains of antiarchs from the sediments of Central Kazakhstan are analyzed. Central Kazakhstan ichthyofauna contains mainly endemic taxons of antiarchs.
S. V. Moloshnikov
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Petrographic and geochemical constraints on the formation of gravity‐defying speleothems
The Depositional Record, Volume 9, Issue 3, Page 413-436, May 2023., 2023 This paper documents a state‐of‐art petrologic and geochemical study of intriguing cave carbonates known as helictites. The properties of aragonitic and calcitic helictites are documented and their origin is discussed. Abstract Cave carbonates, seemingly growing in defiance of gravity, have attracted the community's interest for more than a century ...
Adrian Immenhauser +9 more
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Rivista Italiana di Paleontologia e Stratigrafia, 2011 A new species of Cyrtospirifer is described from the Middle to Upper Givetian of the Western Sahara (Northwest Africa). Cyrtospirifer tindoufensis new species differs in its smaller number and coarser medial and flank plications and equibiconvex shell ...
MENA SCHEMM-GREGORY
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