Results 31 to 40 of about 308 (178)
Advances in the Ordovician graptolite biostratigraphy of the St Petersburg area, Russia [PDF]
Estonian Journal of Earth Sciences, 2009 The Ordovician shallow-water shelf deposits rich in benthic fauna are exposed along the Russian part of the Baltic–Ladoga Klint. Graptolites occur only at some stratigraphic levels, being comparatively numerous in marls and clays and very rare in ...
Suyarkova, Anna A., Koren,Tatyana N.
doaj
The Ultrastructure and Building of Graptolite Dissepiments [PDF]
Acta Palaeontologica Polonica, 2009 Dissepiments or connecting bars between adjacent stipes in rhabdosomes of dendroid graptolites were studied by means of electron microscopy (SEM and TEM). The material, chemically isolated from rock matrix, originating from the Ordovician of Estonia and glacial boulders of Baltic origin found in Poland, is assigned provisionally to the genus ...
Urbanek, Adam, Mierzejewski, Piotr
openaire +2 more sources
The regional stratotype section and point for the base of the Hirnantian Stage (the uppermost Ordovician) at Mirny Creek, Omulev Mountains, Northeast Russia [PDF]
Estonian Journal of Earth Sciences, 2008 A complete Hirnantian sequence comprising the Normalograptus extraordinarius and N. persculptus biozones is well developed at the Mirny Creek section in the Omulev Mountains.
Koren, Tatyana N. +1 more
doaj
Preliminar results of paleontological salvage at Belo Monte Powerplant construction [PDF]
Brazilian Journal of Biology, 2015 In this paper some preliminary fossil specimens are presented. They represent a collection sampled by Belo Monte’s Programa de Salvamento do Patrimônio Paleontológico (PSPP), which includes unprecedented invertebrate fauna and fossil vertebrates from ...
HZ. Tomassi +9 more
doaj +4 more sources
Geophysical Research Letters, Volume 53, Issue 13, 16 July 2026.Abstract The collisional evolution of the micro‐blocks in the northeastern Tibetan Plateau is relatively well constrained. However, the reason why a fragment of the North China Block, the Olongbuluke Block, became separated from North China by the Central Qilian Block (a fragment of the South China Block) remains unclear.
Teng Wang +4 more
wiley +1 more source
The making of pure quartzose sand in continental interiors: Paraná River (Brazil and Argentina)
Sedimentology, Volume 73, Issue 3, Page 802-837, April 2026.ABSTRACT As part of a comprehensive project on sedimentary processes in South America, this study focuses on sediment generation in the intracratonic Paraná Basin and monitors the evolution of sand composition along the Paraná River from central Brazil to the Río de la Plata estuary in Argentina.
Eduardo Garzanti +5 more
wiley +1 more source
Yankuang ceshi, 2019 BACKGROUND The black shale of the Longmaxi Formation in the Upper Yangtze region is rich in graptolites. Most of them were preserved as a carbonaceous film, and enriched in organic-rich layers.
ZHU Cheng-lin +6 more
doaj +1 more source
New Zealand Geological Timescale 2025
New Zealand Journal of Geology and Geophysics, Volume 69, Issue 1, March 2026.New Zealand Geological Timescale 2025 (NZGT 2025) is the first comprehensive update and revision of the New Zealand Geological Timescale in a decade. The criteria used to establish age ranges of New Zealand Stages within the NZGT have been reviewed, calibrated, and revised where required against the 2023/04 International Chronostratigraphic Chart and ...
Christopher D. Clowes +13 more
wiley +1 more source
The succession of Hirnantian events based on data from Baltica: brachiopods, chitinozoans, conodonts, and carbon isotopes [PDF]
Estonian Journal of Earth Sciences, 2008 The Hirnantian (late Ordovician) environment was complex and dynamic. Understanding the correct order of events and their precise correlation with a time scale are extremely important for the development of different kinds of environmental ...
Kaljo, Dimitri +3 more
doaj
Earth and Space Science, Volume 13, Issue 3, March 2026.Abstract This study presents a supervised machine learning approach to constructing a 3D geological model for the Lockington area in Victoria, Australia, by integrating borehole observations, geophysical surveys (magnetic, gravity, and radiometric), and elevation data.
Limin Xu +2 more
wiley +1 more source