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Acritarchs of the Precambrian in mobile zones
Earth-Science Reviews, 1980Abstract This report lists acritarchs found in the various countries studied for I.G.C.P. Project No. 2. The results are provisional as collecting was not always made in accordance with the adopted rules. The research on the acritarchs from different levels in the Precambrian of the countries studied for I.G.C.P. Project No.
B.V. Timofeyev +2 more
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Notes for a Short Course: Studies in Geology, 1987
In 1934 the Geological Society of America published its second Memoir: “Paleozoic Plankton of North America,” by Rudolf Ruedemann. This work was concerned primarily with invertebrates, especially the enigmatic and now-extinct graptolites. The primary producers of that era were virtually unknown; accordingly, the author devoted only a few pages to ...
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In 1934 the Geological Society of America published its second Memoir: “Paleozoic Plankton of North America,” by Rudolf Ruedemann. This work was concerned primarily with invertebrates, especially the enigmatic and now-extinct graptolites. The primary producers of that era were virtually unknown; accordingly, the author devoted only a few pages to ...
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Silurian acritarchs: distribution and trends
Review of Palaeobotany and Palynology, 1974Abstract Using as point of departure data from hundreds of localities with, essentially, Middle Silurian acritarch assemblages, logical constraints on the composition of these assemblages as they can be inferred from geological information, are discussed.
Fritz H. Cramer +1 more
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Neoproterozoic Acritarch Biostratigraphy of China
2020According to studies of the acritarch biostratigraphy in China, the evolution of Neoproterozoic acritarchs roughly involves four stages, from older to younger, including the pre-Doushantuo Stage, the Doushantuo Stage, the Denying Stage and the Meishucun Stage.
Yin Leiming, Yin Chongyu
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Review of Palaeobotany and Palynology, 1967
Abstract Globular organisms which are found in great abundance in the Posidonia shales of northwestern Germany, have been added to the hystrichosphaerids by Eisenack (1954, 1958), who also included the Tasmanites forms from older formations in this group.
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Abstract Globular organisms which are found in great abundance in the Posidonia shales of northwestern Germany, have been added to the hystrichosphaerids by Eisenack (1954, 1958), who also included the Tasmanites forms from older formations in this group.
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Acritarchs in carbonaceous meteorites and terrestrial rocks
SPIE Proceedings, 2013Acritarchs are a group of organic-walled, acid-resistant microfossils of uncertain or unknown origin. Some are thought to represent the cysts or resting stages of unicellular protists (possibly dinoflagellates), chrysophytes (green algae) or other planktonic eukaryotic algae.
Alexei Y. Rozanov, Richard B. Hoover
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Some considerations on acritarch classification
Review of Palaeobotany and Palynology, 1996Abstract Acritarchs are an important group in palynology and especially relevant in lower Palaeozoic sediments. Some 30 years after the group Acritarcha was defined and their systematics examined, their classification should again be debated amongst a wider group of workers.
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Fluorescence intensity in Early Cambrian acritarchs from Estonia
Review of Palaeobotany and Palynology, 1998 Fluorescence properties of Early Cambrian acritarchs were investigated using Leica DM IRBE Laser Scanning Confocal Microscopy (LSCM) with a mercury lamp attached.
Talyzina, NM,
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Biogeography of upper Llandovery and Wenlock acritarchs
Review of Palaeobotany and Palynology, 1995Abstract The world-wide spatial distribution of upper Llandovery and Wenlock acritarch microfloras is assessed using qualitative data, similarity indexes and cluster analysis. The database consists of comprehensive lists of taxa available essentially from eastern North America, South America, western Europe, Baltoscandia, Siberia, North Africa and ...
Alain Le Hérissé, Rémy Gourvennec
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Chapter 9.1 Neoproterozoic Acritarch Evolution
2009Acritarchs are key for unravelling Neoproterozoic biodiversity changes because they represent the only fossil group occurring throughout the era. Their Neoproterozoic evolution is characterised by drastic diversity changes, which, coupled to the occurrence of taxa with restricted stratigraphic range, represents a powerful biostratigraphic tool for the ...
Claudio Gaucher, Peter Sprechmann
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