Results 181 to 190 of about 1,559 (216)

Reflected light microscopy of chitinozoan fragments

Marine and Petroleum Geology, 1985
Abstract Certain optical properties of some Silurian-Ordovician chitinozoans have been measured and their morphology described, using polished, block-mounted samples and polished thin sections. The chitinozoans were found to be optically isotropic and many fine details of their morphology were observed using reflected light microscopy.
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Arenigian chitinozoans from the Klabava formation, Bohemia

Review of Palaeobotany and Palynology, 1984
Abstract The lower Paleozoic succession in Bohemia progressively emerges as a first-order reference in the international stratigraphical scale. This is the reason why investigations have been carried out on chitinozoans from the Klabava Formation which represents the Arenig Series in the Prague Basin.
Florentin Paris, Michal Mergl
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Chitinozoan implications in the palaeogeography of the East Moesia, Romania

Palaeogeography, Palaeoclimatology, Palaeoecology, 2006
Abstract Palaeomagnetic data from Moesia are absent and previous palynological and macrofaunal studies could not show clearly the palaeogeographical position of Moesia between the larger palaeocontinents Gondwana, Baltica, or Avalonia. Cutting samples from three boreholes on East Moesia (SE Romania) have been investigated in this study using S.E.M ...
Marioara Vaida, Jacques Verniers
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The Ordovician chitinozoan biodiversification and its leading factors

Palaeogeography, Palaeoclimatology, Palaeoecology, 2007
Abstract Regional and global dataset now available for almost all of the Ordovician fossil groups have led to a search for the causes controlling the major biodiversification events that occurred during the Ordovician period. A review of the physico-chemical state of the Ordovician world is presented, with an emphasis on the regional or global ...
Achab, Aïcha, Paris, Florentin
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Earliest chitinozoans discovered in the Cambrian Duyun fauna of China

Geology, 2012
Chitinozoans are an enigmatic group of organic-walled marine microfossils with an abundant Lower Ordovician to Upper Devonian fossil record. They achieved maximum species diversity during the Middle Ordovician-Silurian, and their history during the group's acme is well documented.
C. Shen, R. J. Aldridge, M. Williams, T. R. A. Vandenbroucke, X.-g. Zhang   +4 more
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Application of neural networks for chitinozoans recognition in images

Vestnik of geosciences
Paleontological identification of microfauna using automated image recognition represents an innovative practical application of existing software methods for analysis and classification based on computer vision and machine learning technologies. The development of software capable of recognition of Chitinozoans in images will simplify and speed up the
R. Yakupov, K. Gusmanova
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The Ordovician chitinozoan biozones of the Northern Gondwana domain

Review of Palaeobotany and Palynology, 1990
Abstract A formal biozonation is proposed for the Ordovician chitinozoans of the Northern Gondwana Domain. This palaeogeographic province, located at rather high latitudes during the Ordovician, includes southwestern Europe, central Europe, Middle-East, northern Africa and Florida.
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Ordovician chitinozoan zonation of Quebec and western Newfoundland

Journal of Paleontology, 1989
The purpose of this paper is to propose a chitinozoan zonation of the Ordovician of Quebec and western Newfoundland. On the basis of chitinozoan assemblages previously described from various sections, covering almost the entire Ordovician System, 22 biozones, based on first appearance of index species, are distinguished.
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Ordovician and Silurian chitinozoan biozones of western Gondwana

Geological Magazine, 2006
A formal Ordovician–Silurian chitinozoan biozonation for western Gondwana is proposed. This palaeogeographic province includes South America, and was located in medium to high latitudes during Ordovician and Silurian times. Ordovician chitinozoans are known from northern Argentina, southern Bolivia, and Brazil.
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Chitinozoan reflectance: a Lower Palaeozoic thermal maturity indicator

Marine and Petroleum Geology, 1992
Abstract Chitinozoan reflectance ( R ch ) is an innovative technique of thermal maturation determination suitable for Lower Palaeozoic sediments where the established reflectance scale, vitrinite reflectance ( R v ), is not applicable due to the lack of vitrinite.
Paul M. Tricker, John E.A. Marshall, Tim D. Badman   +2 more
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