A new chitinozoan species from the Middle Ordovician of Estonia [PDF]
Estonian Journal of Earth Sciences, 2012 A new species Baltochitina delicata is formally defined. This rare species has been identified in the Aseri Regional Stage (Darriwilian) in North Estonian sections. The genus Baltochitina was known so far only by a single species B. nolvaki, which occurs
Jaak Nõlvak
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Precise chitinozoan dating of Ordovician impact events in Baltoscandia [PDF]
Journal of Micropalaeontology, 1996 Abstract. The chitinozoan biostratigraphy of four Ordovician impact craters has been investigated. Three of these (Tvären, Kärdla and Lockne) contain complete sequences of early Caradoc age, while the Granby crater contains rocks of late Arenig age yielding two bentonitic horizons at their top. Chitinozoans, together with graptolites and other planktic
Yngve Grahn +2 more
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LOWER TO MIDDLE ORDOVICIAN ACRITARCHS AND CHITINOZOANS FROM NORTHERN KARAKORUM MOUNTAINS, PAKISTAN
Rivista Italiana di Paleontologia e Stratigrafia, 2000 The lower Vidiakot section (Chitral, Pakistan) comprises the lower part (Yarkhun Formation and the base of the Vidiakot Formation) of the terrigenous complex transgressively overlying the crystalline basement of Northern Karakorum.
MARCO QUINTAVALLE +2 more
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Morphological variation suggests that chitinozoans may be fossils of individual microorganisms rather than metazoan eggs [PDF]
Proceedings of the Royal Society B: Biological Sciences, 2019 Yan Liang +2 more
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Chitinozoans from the Ordovician-Silurian Boundary Beds in the Eastern Cincinnati Region in Ohio and Kentucky [PDF]
, 1985 Author Institution: Geological Survey of Sweden ; Department of Geology and Mineralogy, The Ohio State UniversityRepresentatives of seven species of chitinozoans, one of which is new (Ancyrochitina belfastensis n.
Bergstrom, Stig M., Grahn, Yngve
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Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China [PDF]
Swiss Journal of PalaeontologySilurian strata are well-developed in the northwest margin of Yangtze Platform. A total of 117 densely spaced argillaceous samples were taken from the Shenxuanyi Member, upper Ningqiang Formation to the lowermost Chejiaba Formation of the Majia section ...
Yangui Li +10 more
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Boundary between the Porkuni and Juuru regional stages in the Neitla section, Estonia [PDF]
Estonian Journal of Earth Sciences, 2023 Conodonts and chitinozoans were studied from the Neitla section, which exposes the boundary between the Porkuni and Juuru regional stages. This level, although not proved biostratigraphically, has been traditionally considered to correspond to the ...
Peep Männik, Jaak Nõlvak
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The detailed Middle to early Late Ordovician faunal succession and δ13Ccarbon chemistry of the Kårehamn drill core, offshore eastern Öland, Sweden: implications for stratigraphy and correlation [PDF]
Estonian Journal of Earth Sciences, 2023 The Middle to lower Upper Ordovician stratigraphy of the KÃ¥rehamn core, drilled ca 7 km offshore to the east of the KÃ¥rehamn village, northeastern Ãland, is presented. The investigated core is one of four drill cores obtained during the preparation of
Svend Stouge +4 more
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The role of clay minerals in the preservation of Precambrian organic‐walled microfossils
Geobiology, Volume 21, Issue 6, Page 708-724, November 2023., 2023 Abstract Precambrian organic‐walled microfossils (OWMs) are primarily preserved in mudstones and shales that are low in total organic carbon (TOC). Recent work suggests that high TOC may hinder OWM preservation, perhaps because it interferes with chemical interactions involving certain clay minerals that inhibit the decay of microorganisms.
C. R. Woltz +3 more
wiley +1 more source
Latest Ordovician age of the Spinachitina fragilis Chitinozoan Biozone in Baltoscandia [PDF]
Estonian Journal of Earth Sciences, 2023 The global Spinachitina fragilis Chitinozoan Biozone has been considered the lowermost Silurian zone in most publications. S. fragilis was first described from the Ohesaare drill core, Estonia, and utilised as a Baltic regional zonal taxon together with ...
Jaak Nõlvak, Yan Liang, Olle Hints
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