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Search Results: 1 - 10 of 2290 matches for " Upper Carboniferous "
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Two new petalodont teeth (Chondrichthyes, Upper Carboniferous) from the Karavanke Mountains, Slovenia
Anton Ramov?
Geologija , 1997,
Abstract:
Sedimentación lacustre glaci-dominada en la Formación Tarija (Carbonífero), Sierra de Aguaragüe, Noroeste Argentino
Del Papa,Cecilia; Martínez,Lisandro;
Revista de la Asociaci?3n Argentina de Sedimentolog?-a , 2001,
Abstract: the tarija formation (macharetí group) is mainly composed by gray diamictites which have been deposited under the glacial sedimentation that took place during the upper carboniferous period in gondwanaland. this paper describes the facies and facies associations of itacuamí and tarija formations of five section located in the aguaragüe range, sub-andean belt of salta province, argentina (fig. 1). the tarija formation outcrops almost completely (620m thick) and consist of gray diamictites, interbedded with fine sandstone levels and laminated mudstones. the basal contact is transitional with the itacuamí formation and the upper contact is an erosive unconformity with las pe?as formation (mandiyutí group). the itacuamí-tarija cycle can be divided into three sections, according to the facies associations considered. the lowermost section is formed by the facies association i (fai of fig. 2), composed by laminated mudstones (fl and fm) and thin bedded sandstones (st and sm). towards the top of the basal section, 34 m of white coarse and thickening upward sandstones (st, sh, sr and fl) intercalate. these also show a gentle downstream accretion structure (figs. 2 and 3-a). the middle section is formed by the facies association ii (fig. 2), which is composed by different levels of stratified and massive sandy muddy diamictites (dms and dmm) and mudstones (fld). in these diamictite, it is quite common to find scattered faceted and striated clasts (fig. 3-f and 4-c). there are two kinds of interbedded sandstones, coarsening - upward succesions and fining upward ones, both showing deformed, folded and dewatering structures (figs. 3-d and 3-e). the fl facies, composed by shale and siltstones have plenty of outsized clasts, which have been interpreted as dropstones (facies fld). the upper section (fa iii, fig. 2) is made up of massive diamictites (dmm, figs. 4-c and d) and stratified ones with frequent traction current structures (sr). in this section, levels of lenticular sands
A Review of Orbiculoidea saltensis Reed, Brachiopoda: Discinidae, of the Upper Carboniferous of Argentina
Lech,Roberto Ricardo;
Serie correlaci?3n geol?3gica , 2011,
Abstract: the purpose of this paper is to present a review of o. saltensis reed, presenting a new diagnosis based in the study of some articulated specimens. these fossils were found in the marine sedimentary rocks of the late paleozoic of the precordillera of mendoza and san juan, argentina. also, the species described by reed is compared with other species of discinoid brachiopods from the paleozoic of south america, and some of the proposals for the taxonomic identification of them are modified.
Plant fossils in the Carboniferous beds of the motorway route at Bizovik
Tea Kolar-Jurkov?ek,Bogdan Jurkov?ek
Geologija , 2002,
Abstract: Study of fossil plants that were found during construction work of the Eastern Ljubljana motorway at Bizovik demonstrated that similar plants flourished in the uniform Euroamerican floristic area that extended in the Late Carboniferous from the present NorthAmerica across Europe to Asia. The collected fossil flora consists predominantly of Pteridophyta, represented by Equisetopsida, Lycopodiopsida and Polypodiopsida. Gymnospermae are also present, represented by Pteridospermopsida and Cordaitanthales.
Shenzhousia qilianshanensis gen. et sp. nov. (Protodonata, Meganeuridae), a giant dragonfly from the Upper Carboniferous of China
ZHANG Zhijun,HONG Youchong,LU Liwu,FANG Xiaosi,JIN Yuegao,
ZHANG Zhijun
,HONG Youchong,LU Liwu,FANG Xiaosi,JIN Yuegao

自然科学进展 , 2006,
Abstract: A new dragonfly of family Meganeuridae Shenzhousia qilianshanensis gen. et sp. nov., discovered from Ningxia Hui Autonomous Region in North China, is described in the present paper. It has an estimated wingspan of about 450?500 mm and may be the largest fossil insect in Late Carboniferous Namurian Stage discovered by far. The new species is referred to Meganeuridae because of the presence of the characteristic oblique vein between anterior branch of radius (RA) and posterior branch of radius (RP) near the base of RP2. It differs from other genera within the family in the following characteristics: Precostal area short and not extending to the midwing; posterior branch of subcostal vein short, merging into costal vein near the level of originating point of IR2; RP forking earlier than anterior branch of media basally; RP1+2 and RP3+4 parallel and close to each other for a long distance, and then diverge gradually surpass midwing.
Palinología de la Formación El Trampeadero (Carbonífero Superior), La Rioja, Argentina: significado bioestratigráfico
Gutiérrez,Pedro Raúl; Barreda,Viviana D.;
Ameghiniana , 2006,
Abstract: a diverse and relatively well preserved palynological assemblage recovered from el trampeadero formation (upper carboniferous, paganzo basin) is here described. this assemblage is composed by elements of continental origin: woody particules, cuticules, spores, pollen grains and algae. the dominant spore species are apiculiretusispora variornata (menéndez and azcuy) menéndez and azcuy, ahrensisporites cristatus playford and powis, anapiculatisporites argentinensis azcuy, apiculatisporites variornatus di pasquo et al ., convolutispora muriornata menéndez, cordylosporites sp. cf. c. asperdictyus (playford and helby) dino and playford, cristatisporites menendezii (menéndez and azcuy) playford, c. stellatus (azcuy) gutiérrez and limarino, psomospora detecta playford and helby, raistrickia sp. cf. r . accincta playford and helby, reticulatisporites magnidictyus playford and helby, r. passapectus ottone, spinozonotriletes hirsutus azcuy, verrucosisporites patelliformis (menéndez) gutiérrez and césari. moreover, dibolisporites disfacies jones and truswell was recorded for the first time for the paganzo basin. monosaccate ( plicatipollenites spp., cannanaropollis spp.) and bisaccate ( alisporites sp., limitisporites sp.) pollen grains were also recognized for this unit. considering the known chronostratigraphic ranges of some key species, a late carboniferous (late namurian-westphalian) age is here proposed for the el trampeadero formation. the abundance of palynomorphs with affinities to higro and hidrophitic plants (lycophyta, filicopsidas) agree with the lacustrine environment suggested by sedimentological evidences.
Depositional environment of Upper Carboniferous – Lower Permian beds in the Karavanke Mountains (Southern Alps, Slovenia)
Matev? Novak
Geologija , 2007,
Abstract: Late Paleozoic rocks were studied in detail in the Dov anova soteska section. The Upper Carboniferous sedimentary succession, correlated with upper part of Auernig and SchulterkofelFm. in the Carnic Alps, indicates cyclic clastic-carbonate deposition in a coastal to shallow marine ramp setting with strong influenceofcoarse-grainedfluvial-deltaicsilici-clastics from the hinterland, storm dominated regime of nearshore sediments, and offshore algal buildups. The Lower Permian sequence is developed differently from its time equivalentGrenzland Fm. and is subdivided into Dov anova soteska Fm., Born Fm., and Rigelj beds. It is marked by the formation of a reef mound on the platform margin. Open-marine inner platform close to the marginal shoals represented the depositional environment of the mixed carbonate-siliciclastic sediments. Thus, a platform evolution from a ramp into a rimmed shelf is suggested.
Younger Paleozoic, Mesozoic and Tertiary oolitic and oncolitic beds in Slovenia – An Overview
Stevo Dozet,Bojan Ogorelec
Geologija , 2012,
Abstract: Oolitic and oncoidal rocks, microfacies, depositional environments and their stratigraphic ranges in Sloveniaare subjects of this article. Various types of calcareous ooids are present in the Upper Carboniferous, Permian andTertiary (Paleocene and Miocene) beds and specially at many levels in an up to 6000 meters thick statigraphic successionof the Mesozoic age. Sedimentological investigations have been carried out specially in the Triassic andJurassic beds. The ooids occurring in the shallow-water and intertidal carbonate environment have been groupedinto seven types and oncoids into four types. Oncoids are rather more aboundant in Carnian and Norian/Rhaetianage. Late dolomitization of some oolitic beds is next to cementation the main diagenetic feature.
Conditions of accumulation and sedimentary architecture of the upper Westphalian Cracow Sandstone Series (Upper Silesia Coal Basin, Poland)
Marek DOKTOR
Annales Societatis Geologorum Poloniae , 2007,
Abstract: The Cracow Sandstone Series (upper Westphalian) forms the uppermost segment of the coal-bearing succession that makes up the bulk of the Variscan foredeep-basin fill in the Upper Silesia Coal Basin. The series, up to 1640 m in stratigraphic thickness, consists entirely of non-marine deposits. Fiveteen lithofacies have been distinguished in the sediments of this series. The Cracow Sandstone Series is subdivided here in two lithofacies associations. The sandstone association consists mainly of medium- to coarse-grained sandstones that form packages up to several tens of metres thick (max. 140 m), with surfaces of erosion at base. These bodies are separated by less voluminous packages of the mudstone association that consists mainly of mudstones and coal seams, which locally make up the predominant part in the sequences of this association. The sediments of the sandstone association are believed to have originated within wide channel tracts of distal sandy braided rivers. The sediments of the mudstone association with the interbedded coal seams are interpreted as floodplain deposits. The predominant type of peat bogs, represented now in the coals of the Cracow Sandstone Series, were wet forest swamps. The peat bogs were probably slightly domed and their margins received clastic material from adjacent channels. This resulted in the frequent lateral splitting of the coal seams. The large-scale splitting of seams is associated with lateral transition of fine-grained floodplain deposits into coarse-grained channel deposits. The vertical alternation of the channel and floodplain deposits is the result of natural processes on an alluvial plain that resulted in shifting positions of depositional environments, first of all avulsion of the whole fluvial tracts. The coal seams in the Cracow Sandstone Series do not form extensive sheets of persistent thickness, and their geometry depends on the course and evolution of the network of fluvial tracts in the alluvial system. The internal geometry of the Cracow Sandstone Series was controlled to a large extent by differential compaction of sediments, notably by rapid compaction of peat.
The taxonomy of middle Westphalian medullosalean foliage known as ' Alethopteris grandinioides early form' from the Central and Western Bohemian basins
?im?nek Z,Cleal C J
Bulletin of Geosciences , 2002, DOI: 10.3140/bull.geosci.2002.01.061
Abstract: Fossils from the Whetstone Horizon of central Bohemia, previously referred to as the 'early form of A. grandinioides Kessler', are shown to be indistinguishable in pinnule morphology and venation from Alethopteris distantinervosa Wagner. This new evidence allows the diagnosis of A. distantinervosa to be emended, providing better information on its morphological variation and epidermal structure. A. distantinervosa occurs in floras of late Duckmantian to Bolsovian and possibly early Westphalian D age in central Bohemia, Saar-Lorraine, Ibbenbüren, and South Staffordshire. A. grandinioides Kessler sensu Wagner, non Kessler s.s. (= A. pseudograndinioides Zodrow and Cleal) does not appear to occur in floras older than middle Westphalian D in age.
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