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Geophysical Monograph Series, Page 305-323., 2021 Exploring the links between Large Igneous Provinces and dramatic environmental impact
An emerging consensus suggests that Large Igneous Provinces (LIPs) and Silicic LIPs (SLIPs) are a significant driver of dramatic global environmental and biological changes, including mass extinctions.
Brian Kendall +2 more
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THE AMERICAN UPPER ORDOVICIAN STANDARD [PDF]
Geological Society of America Bulletin, 1961 The large number of classifications of the type Cincinnatian (Ordovician) are to a great extent variations of a few fundamental concepts. Each of these elements is at least 40 years old and founded in the more rigid stratigraphic faiths of those times.
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A geomagnetic polarity stratigraphy for the Middle and Upper Ordovician [PDF]
Palaeogeography, Palaeoclimatology, Palaeoecology, 2021 Magnetostratigraphic studies of the Ordovician provide evidence for the nature of core-mantle boundary interactions, and provide means for dating and correlation across differing environmental regimes. We provide new magnetostratigraphic data from the Middle and Upper Ordovician, compiling this into a polarity chronostratigraphic scale for the ...
Hounslow, Mark +6 more
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Global palaeogeographical implication of acritarchs in the Upper Ordovician
Estonian Journal of Earth Sciences, 2023 The EarlyâMiddle Ordovician peri-Gondwana and Baltica acritarch provinces are easily recognizable, illustrating a clear provincialism of global phytoplankton. However, acritarch assemblages have been reported to become increasingly similar towards the Late Ordovician, revealing a general cosmopolitanism, although, based on more recent studies ...
Yan Kui +4 more
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Cornulitids from the Upper Ordovician of northwestern Russia [PDF]
Carnets de géologie (Notebooks on geology), 2017 Four cornulitid species occur in the Rakvere Regional Stage in NW Russia. The new species Conchicolites rossicus is here described; it is the earliest known Conchicolites from the Ordovician of Baltica. The new species has very small tubes with sharp, strong and regular annulations.
Olev Vinn, Anna Madison
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Machaeridians from the Middle and Upper Ordovician of the Argentine Precordillera
Geological Journal, 2012 The machaeridians are marine Palaeozoic annelids, which developed a dorsal skeleton composed of calcite sclerites, achieving a world‐wide distribution from the Early Ordovician to the Middle Permian. The absence of records from this group is notable in Argentina in spite of intense studies of Palaeozoic rocks.
Ortega, Gladys del Carmen +2 more
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Deep Underground Science and Engineering, EarlyView.The fused data extracted from the distributed monitoring system as the data basis, combined with dynamic geological data, are imported into a deep learning model. As the geological conditions of mining and excavation change, the risk of water inrush at the working face is retrieved in real time.
Yongjie Li +4 more
wiley +1 more source
Geological Journal, EarlyView.Our petrochemical studies on ~1.2 Ga granitoids of the Natal Metamorphic Belt, South Africa, do not suggest any property similar to Phanerozoic‐style subduction‐related granitoids. Plot of Kotongweni Tonalite in Y versus Sr diagram (after Moyen 2011), note that most samples have Sr/Y < 50.
Palesa Leuta +2 more
wiley +1 more source
Journal of Quaternary Science, EarlyView.ABSTRACT The Cadí Massif (42°17′09″ N, 1°38′11″ E; 2649 m a.s.l.) in the southeastern Pyrenees preserves clear evidence of Late Pleistocene glaciation, although previous research has focused almost exclusively on its northern slope. By contrast, the southern slope has remained largely unexplored.
M. Oliva +5 more
wiley +1 more source
A talus rock glacier in Nantlle Valley, North Wales
Journal of Quaternary Science, EarlyView.ABSTRACT Landforms comprising mixtures of fine and coarse sediment and deposited during late glacial times are ubiquitous in the British mountains. In many cases, their interpretation has often proved contentious; as a result, the non‐generic term discrete debris accumulations (DDA) has been used to describe them and, over the last 50 years, some have ...
Stephan Harrison, Ed Anderson
wiley +1 more source