Search results for "Carboniferous"
showing 10 items of 55 documents
New fossil arthropods (Notostraca and Insecta: Syntonopterida) in the Continental Middle Permian of Provence (Bas-Argens Basin, France).
2009
9 pages; Apart frequent and relatively common ichnites, only a few body fossils (Ostracoda) have been mentioned in the Red Continental Permian formations of Provence till these last years. During 2006 and 2007 field researches, new arthropods have been discovered in the Pradineaux Formation of the Bas-Argens. They are Triopsidae (Crustacea, Notostraca) and an insect wing (Syntonopteridae) corresponding to a new genus and species Gallolithoneura butchlii gen. et sp. n. This latter is the first insect record in the Permian of Provence and the youngest one of this enigmatic Carboniferous paleopteran family. As in the other French Permian basins (Lodève, Saint-Affrique), these discoveries demon…
First occurrence of fossil vertebrates from the Carboniferous of Colombia
2020
Data concerning Paleozoic vertebrates from the South American continent are still scarce. In Colombia, occurrences were until now restricted to the Late Devonian fish assemblage from Floresta and, ...
Revision of Permo-Carboniferous griffenflies (Insecta: Odonatoptera: Meganisoptera) based upon new species and redescription of selected poorly known…
2009
33 pages; International audience
Scheelite-Bearing Metalliferous Sequences of the Peloritani Mountains, Northeastern Sicily (with some Remarks on Tungsten Metallogenesis in the Calab…
1988
The Peloritani Mountains (Northeastern Sicily) are part of a segment of the Hercynian chain recognized in the Calabrian-Peloritan Arc, geotectonically defined by a pre-Hercynian crystalline basement (Aspromonte Nappe + Mandanici Unit) overthrust and overturned on its Paleozoic (Cambro-Ordovician up to Devonian Carboniferous) volcanosedimentary cover. Tungsten (scheelite) and associated polymetallic stratabound ores, more or less intensely affected by the pre-Hercynian and Hercynian tectonometamorphic events, are confined to the pre-Hercynian basement. In particular, the most significant scheelite-tourmaline (arsenopyrite) and scheelite-carbonate-quartz (albite) mineralizations could be cons…
Ediacaran, Early Ordovician and early Silurian arcs in the South Tianshan orogen of Kyrgyzstan
2020
Abstract The oldest magmatic rocks from the South Tianshan orogen of Kyrgyzstan (STS) are important for better understanding of the Neoproterozoic and early Palaeozoic evolution of the southwestern Central Asian Orogenic Belt. Bulk rock major and trace element and Sm-Nd isotopic composition and zircon U-Pb ages of granitoids from melange blocks reveal two previously unknown episodes of arc magmatism in the STS orogen of Kyrgyzstan, namely, the Ediacaran (ca. 624 Ma) and Early Ordovician (ca. 472 Ma) episodes. Moderately positive ɛNd(t) value of + 5.8 of the Ediacaran granodiorite indicates a mainly juvenile source for this rock. Negative ɛNd(t) value of −9.1 for the Early Ordovician granodi…
Trends and patterns in the evolution of vascular plants: macroevolutionary implications of a multilevel taxonomic analysis
2010
Cascales-Minana, B., Munoz-Bertomeu, J., Ros, R., Segura, J. 2010: Trends and patterns in the evolution of vascular plants: macroevolutionary implications of a multilevel taxonomic analysis. Lethaia, 10.1111/j.1502-3931.2009.00212.x Studying the macroevolutionary patterns of vascular plants from the Silurian to the present-day provides a global record of plant life history. Evolutionary rates (origination, extinction and diversification) for families, orders, classes and divisions were analysed, as was abundance and richness for 21 time intervals. An accumulative analysis, based on the total plant fossil record, the accumulated extinctions and relative diversity, was also carried out. The d…
New insights into the reading of Paleozoic plant fossil record discontinuities
2011
Studying the discontinuity patterns of Paleozoic vascular plants provides a global vision of these key events from the multivariate methods viewpoint. Non-metric multidimensional scaling, detrended correspondence analysis and cluster analysis have been employed together with a set of diversity and abundance measures and an evaluation of the geologic constraints from the plant fossil record data. The results reveal four clear significant discontinuities in terms of taxonomic composition and record representativeness during the early-middle Devonian, Devonian–Carboniferous, Mississippian–Pennsylvanian and early-late Permian. Due to the controversial character of the plant fossil record data a…
Lower Bashkirian fusulinoideans from the upper part of the Tagnana Formation (Carboniferous, NW Algeria)
2021
The upper member of the Tagnana Formation of the Djebel Bechar Group (informally the Tagnana-3 or Tagnana Ill member) yielded fusulinoideans and other related foraminifera of the genera Pseudoendothyra (rare), Pseudostajfella (Semistaffella) (rare), Millerella, Pseudonovel/a, Plectostaffella, Eostaffella and Mediocris. The presence of Eostaffellina (rare) and Endostaffella is doubtful. The difference between Millerella and Eostaffella cannot be adequately defined by evolute versus involute coiling. Pseudonovella Kireeva, 1949 is redefined to include Seminovella Rauzer-Chernousova, 1951. The foraminifera are from two samples, one from close to the top and the other from near the base of the …
The Variscan structural and metamorphic evolution of the eastern Southalpine basement
1994
The basement of the Southern Alps (northern Italy) belongs to the southernmost part of the European Variscan mountain belt. In contrast to other areas of the Alps, the post-Variscan metamorphic and tectonic overprint is weak and therefore permits the unravelling of the Variscan tectonometamorphic evolution of this region. Overprinting criteria and the mapping of the penetrative structural elements (S2 and L2) allow three deformational events to be distinguished. Major Variscan deformation (D2) in the Southern Alps commenced in the Carboniferous and lasted until the end of the Late Carboniferous. Tectonic movement during D2 was north-directed and was accompanied and followed by greenschist f…
Timing of granitoid magmatism in the eastern mid-German crystalline rise
2001
Abstract The eastern parts of the mid-German crystalline rise (MGCR) are exposed in the Spessart, Ruhla and Kyffhauser crystalline complexes and known from boreholes in the region of Dessau. In this study we determined igneous formation ages of granitoid intrusives and orthogneisses from this part of the MGCR using the Pb/Pb single zircon dating technique. The intrusion ages of the granitoids range from ∼489 to ∼302 Ma (i.e. from lower Ordovician to upper Carboniferous). The grouping of these ages marks several distinct magmatic episodes during the Variscan orogeny, with a major peak at the end of the lower Carboniferous. We tentatively suggest the following geodynamic scenario for the orig…