Results 151 to 160 of about 2,004 (204)

Ordovician chitinozoan biozonation of the Brabant Massif, Belgium

Review of Palaeobotany and Palynology, 2000
Chitinozoans from seven Ordovician units (Abbaye de Villers, Tribotte, Rigenée, Ittre, Bornival, and Brutia formations and a new unnamed unit, here provisionally called the Asquempont unit) belonging to the mainly concealed Brabant Massif, Belgium are described herein. Fifty-six samples were taken from rocks cropping out at the south-eastern rim of the
J, Samuelsson, J, Verniers
openaire   +2 more sources

Age constraints of the Hungshihyen Formation (Early to Middle Ordovician) on the western margin of the Yangtze Platform, South China: New insights from chitinozoans

, 2020
The Hungshihyen Formation represents the Lower to Middle Ordovician near-shore siliciclastic deposits on the western margin of the Yangtze Platform, South China. However, its age is still debated, largely because of insufficient studies.
Yan Liang, Guangxu Wang, T. Servais, R. Wu, J. Nõlvak, O. Hints, Xin Wei, Fangyi Gong, Guanzhou Yan   +8 more
semanticscholar   +1 more source

Caradocian chitinozoans from the Central Basin, Tennessee

Review of Palaeobotany and Palynology, 1998
Abstract Chitinozoans occur in low numbers and diversity in all formations of the Caradocian Stones River and Nashville Groups of the Central Basin, Tennessee. Sixteen species have been found in the interval studied: Belonechitina micracantha, B. robusta, B. seriespinosa, B. wesenbergensis, Calpichitina lata, Conochitina elegans, C.
William G. Siesser, James W. Hendley, Thomas E. Kessler, John C. Marler, Eleanor T. Wehner   +4 more
openaire   +2 more sources

Ultrastructural studies of some chitinozoan vesicles

Lethaia, 1980
Four species of Ordovician Chitinozoa from Oland, Sweden, Cyathochitina stentor, Desmochitina minor, Lagenochitina esthonica, and Lagenochitina tumida, have been investigated by transmission electron microscopy. There is very great variation in the vesicle wall ultrastructure of the specimens studied.
Yngve Grahn, Björn A. Afzelius
openaire   +1 more source

Chitinozoans from the upper Frasnian (Upper Devonian) of Armenia: biostratigraphical and palaeobiogeographical implications

Palynology
This paper marks the first systematic study of chitinozoans from the Upper Devonian succession of Armenia. The examined material, derived from the upper Frasnian strata of the Ertych section, contributes to our understanding of the diversity of ...
Vitalina Lokteva, Gayane V Kirakosyan, S. C. Camina, T. De Backer, A. Grigoryan, T. Danelian, V. Serobyan   +6 more
semanticscholar   +1 more source

The biostratigraphy and palaeogeography of acritarchs, chitinozoans, and cryptospores from the Upper Ordovician Ghelli Formation, Khoshyeilagh region, southern Caspian Sea, Alborz Mountains, northern Iran

Palynology
In the Khoshyeilagh region, 70 km north of Shahroud city, northern Iran, a siliciclastic succession of Lower Palaeozoic strata, including the Lalun, Mila, Lashkarak, and Ghelli formations, occurs alongside igneous rocks.
M. Ghavidel-syooki
semanticscholar   +1 more source

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
openaire   +1 more source

Raman spectroscopy of chitinozoans as a maturation indicator

Organic Geochemistry, 1995
Abstract Micro-Raman spectra were acquired from a series of individual chitinozoans of low ( R ch 0.6%) to high thermal maturity ( R ch 5.1%). This provides information on their molecular and structural characteristics. All spectra show two broad bands on a fluorescent background at ∼ 1600 and 1355 cm −1 .
S. Roberts, P.M. Tricker, J.E.A. Marshall   +2 more
openaire   +1 more source

Early diversification of Ordovician chitinozoans on Baltica: New data from the Jägala waterfall section, northern Estonia

Palaeogeography, Palaeoclimatology, Palaeoecology, 2019
Chitinozoans are a group of biostratigraphically valuable microfossils which appeared in the Tremadocian and diversified during the rest of the Great Ordovician Biodiversification Event, to become extinct in the Devonian.
J. Nõlvak, Yan Liang, O. Hints
semanticscholar   +1 more source

Middle–Late Silurian and Early Devonian Chitinozoans from the Chacoparaná Basin, Salta Province, Argentina

Ameghiniana
. The first chitinozoan assemblages from the middle–late Silurian and Early Devonian strata of the Copo Formation in the Rivadavia borehole, Salta province, Argentina, are described.
S. C. Camina, C. V. Rubinstein, Anthony Butcher, J. Lovecchio   +3 more
semanticscholar   +1 more source