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1.
Early Carboniferous palynological assemblages from the SM-4 well located in the Llanos Orientales Basin constitute the only definitively geological evidence of Carboniferous strata in this Basin. Stratigraphically significant species include: Anapiculatisporites concinnus, Apiculiretusispora mutiseta, Grandispora spiculifera, Indotriradites dolianitii morphon, Spelaeotriletes pretiosus and Prolycospora rugulosa. The presence of scarce acritarchs indicates a shallow marine environment. A Tournaisian age, probably reaching the Viséan, is proposed for the interval 2010-2340 ft based on the presence of distinctive spore species with previous records in the Viséan and Tournaisian of Western Europe and Western Gondwana. This report increases the knowledge about the distribution and composition of the Early Carboniferous palynological assemblages in Northern Gondwana.  相似文献   

2.
For the first time the genusEuthycarcinus could be identified in the Upper Carboniferous system. A new species,E. ibbenburensis, is described and its taxonomic position discussed. Evidence is given by sedimentological as well as by morphological data thatEuthycarcinus was part of the Upper Carboniferous limnic fauna.  相似文献   

3.
In 1930W.E. Schmidt described all known crinoids from the German Early Carboniferous, including the Etroeungt beds of Germany, which are now judged to be latest Devonian (Famennian) in age. On a global basis, Famennian camerate crinoids generally show a closer relationship to succeeding Early Carboniferous faunas than they do to older Frasnian or Middle Devonian crinoids, which also is the case for the Strunian fauna. Holdovers from older Devonian faunas include, among others,Adelocrinus, a descendant of olderArthroacantha, in England and Germany, andPetaloblastus, which is one of the youngest genera of the blastoid family Hyperoblastidae. Precursors of younger Early Carboniferous groups include platycrinoids, primitive actinocrinoids, dichocrinoids, and the blastoid genusDoryblastus, which is one of the oldest members of the family Orbitremitidae. All of these groups, which became important parts of the Early Carboniferous crinoid and blastoid radiation, give Famennian crinoid faunas much more of an Early Carboniferous than a Devonian aspect. Rhipidocrinus schmidti n. sp. is erected for specimens that originally were reported from the Etroeungt asRhodocrinus uniarticulatus. We judge that there are currently four valid species assigned toRhipidocrinus: R. crenatus, R. perloricatus, R. praecursor, and our new species,R. schmidti. Hydriocrinus ratingensis Schmidt is reassigned to ?Sostronocrinus. We note thatSchmidt (1906), notJaekel (1906) as has been reported previously, is the author ofRhipidocrinus perloricatus. Owing to the poor preservation of the Etroeungt material, we regard the namePlatycrinites wunstorfi Schmidt 1930 to be a nomen nudum.  相似文献   

4.
《Comptes Rendus Palevol》2005,4(1-2):109-121
Palaeoecological and palaeogeographical inferences from Early Carboniferous bivalves of the Ancenis Basin (Variscan belt, France). In the basal part of the Ancenis Formation, of Dinantian age, greenish to purple mudstones display a few bivalves, assigned to the genera Lithophaga, Modiolus, and Naiadites. Because Naiadites is considered to be a non-marine bivalve, and is only previously reported in Scotland in Dinantian rocks, a brackish environment can be assumed for the Ancenis Basin during the Early Carboniferous. To cite this article: M. Ballèvre, H. Lardeux, C. R. Palevol 4 (2005).  相似文献   

5.
The family Cacurgidae is revised. In addition to the type genus Cacurgus Handlirsch, 1911 from the Upper Carboniferous of the United States, Ideliopsis ovalis Carpenter, 1948 from the Lower Permian of the United States and Kitshuga ryzhkovae gen. et sp. nov. from the Upper Permian of Russia are included in this family. An undescribed genus from the Upper Carboniferous of Argentina (Béthoux and Nel, 2002) is also placed in this family. Relationships of Cacurgidae are discussed, and the family is included in the order Grylloblattida.  相似文献   

6.
Devonian and Carboniferous dendroid graptolites from Belgium are evaluated and partly revised. New finds in two different stratigraphic intervals of the ‘Carrière de Lompret’, an active quarry exploiting Frasnian limestones and shales east of Frasnes-lez-Couvin, allow the identification of Callograptus sp. and Dictyonema fraiponti, both belonging to the dendroid family Acanthograptidae. The relatively high diversity of the dendroid graptolite fauna from the Viséan Marbre noir de Denée, one of the few Carboniferous graptolite faunas in the world, can be shown to be based on astogenetic and preservational aspects. Nearly all known specimens can be included in the highly variable Dictyonema fraiponti, a fan-shaped large dendroid species with complex stipes formed from tubular thecae, possessing simple to complex bridges connecting adjacent stipes. Some of the graptolite material is well preserved and provides important information on the tubarium construction of Devonian to Carboniferous dendroid graptolites and, thus, is highly significant for a taxonomic and phylogenetic understanding of the youngest dendroid graptolite faunas worldwide. The genera Callograptus and Ptiograptus are revised based on their type species (Callograptus elegans from Quebec, Canada; Ptiograptus percorrugatus from the Silurian or Devonian of Kentucky, USA) and referred to the Acanthograptidae.  相似文献   

7.
Geochemical models of atmospheric evolution predict that during the late Carboniferous, ca. 300 Ma, atmospheric oxygen and carbon dioxide concentrations were 35% and 0.03%, respectively. Both gases compete with each other for ribulose-1,5-bisphosphate carboxylase/oxygenase-the primary C-fixing enzyme in C3 land plants: and the absolute concentrations and the ratio of the two in the atmosphere have the potential to strongly influence land-plant function. The Carboniferous therefore represents an era of potentially strong feedback between atmospheric composition and plant function. We assessed some implications of this ratio of atmospheric gases on plant function using experimental and modelling approaches. After six weeks growth at 35% O2 and 0.03% carbon dioxide, no photosynthetic acclimation was observed in the woody species Betula pubescens and Hedera helix relative to those plants grown at 21% O2. Leaf photosynthetic rates were 29% lower in the high O2 environment compared to the controls. A global-scale analysis of the impact of the late Carboniferous climate and atmospheric composition on vegetation function was determined by driving a process-based vegetation-biogeochemistry model with a Carboniferous global palaeoclimate simulated by the Universities Global Atmospheric Modelling Programme General Circulation Model. Global patterns of net primary productivity, leaf area index and soil carbon concentration for the equilibrium model solutions showed generally low values everywhere, compared with the present day, except for a central band in the northern land mass extension of Gondwana, where high values were predicted. The areas of high soil carbon accumulation closely match the known distribution of late Carboniferous coals. Sensitivity analysis with the model indicated that the increase in O2 concentration from 21% to 35% reduced global net primary productivity by 18.7% or by 6.3 GtC yr-1. Further work is required to collate and map at the global scale the distribution of vegetation types, and evidence for wildfires, for the late Carboniferous to test our predictions.  相似文献   

8.
9.
New outcrops of Carboniferous sediments in the Zone axiale of the Central French Pyrénées yielded florae and faunae of Namurian age. Among this lot of fossils, the Molluscs Bivalvia are worth particular attention. They were collected from detritical layers, located near the Ardengost Limestone; the various lithological characteristics of these layers are briefly described. The palaeontological study allows to record 13 species; among them, 11 were previously mentioned from the Namurian but it is underlined here that the determination of species remains difficult. The clear predominance of the epifauna and the fineness of the sediments agree to suggest quiet environments. At last, this fauna corroborates the great rise, during the Upper Carboniferous, of the class Pteriomorpha amongst the Bivalvia.  相似文献   

10.
Noeggerathia dickeri n.sp. is described from the Lower Carboniferous Upper Sandstone Formation of southwestern Sinai.  相似文献   

11.
《Palaeoworld》2015,24(4):470-478
Two new species of flexible crinoids of the genus Cibolocrinus (Crinoidea, Flexibilia) from the Upper Carboniferous of the Moscow Region are described: C. kutasovi (Moscovian Stage, Podolskian Regional Substage) and C. gerassimovi (Gzhelian Stage, Dobryatinian Regional Substage). The first species, C. kutasovi, belongs to a group with low cone shaped cups that first appeared in the Moscow Basin and then spread to the Midcontinent of North America. In one specimen of C. gerassimovi the smallest infrabasal plate is situated in the A ray, which is not typical for flexible crinoids. A poorly preserved crown of Cibolocrinus sp. from the Upper Carboniferous (Gzhelian Stage) of the Darvaz Ridge (western Pamir, central Tajikistan) is also described. The described specimens of Cibolocrinus from the Moscow Region and the Darvaz Ridge are the first reliable specimens of this genus described from Europe and Asia.  相似文献   

12.
《Palaeoworld》2023,32(3):411-428
In southwestern Mongolia, conodonts from the Indert Formation at its type locality in Shine Jinst were investigated to improve regional and global correlation of the uppermost Devonian–lowermost Carboniferous. The abundance and diversity of the conodont fauna is quite low in general, whereas representatives of Siphonodella, Protognathodus, Pseudopolygnathus, Polygnathus and Bispathodus have been collected from the Indert-Uul section. Five conodont biointervals, from the Bi. costatus-Pr. kockeli Interregnum (ckI) to the Siphonodella sandbergi Zone, could be recognized from the top Heermorit Member and the lower part of the Shombon Member, while the middle and upper parts of the Shombon Member cannot be zoned based on the conodonts. Absence of index fossils Si. sulcata, Pr. kuehni and Pr. kockeli hampered precise recognition of the Devonian–Carboniferous boundary (DCB) at Indert-Uul, but this transition is well delineated by typical uppermost Famennian and Tournaisian conodont assemblages. The DCB is tentatively placed at the base of the Shombon Member, consistent with the lithological boundary and the resuming of carbonate production during the DCB transitional interval.  相似文献   

13.
14.
New finds of Late Palaeozoic arachnids, based on three well-preserved carapaces from the Carboniferous of Russia and Ukraine and one complete, albeit poorly preserved, specimen from the Permian of Kazakhstan, are described. The spider genus Arthrolycosa is reported from the Late Carboniferous (Late Pennsylvanian: Kasimovian–Gzhelian) of Chunya in the Tunguska Basin of Siberia; it is the first find of a spider outside the Carboniferous tropics. Another fossil assigned to the same genus comes from the Late Carboniferous (Early Pennsylvanian: Bashkirian) of Kamensk–Shakhtinsky in the Donets Basin of Russia; it is probably the oldest fossil spider known. A thelyphonid (whip scorpion) carapace is described from the Late Carboniferous (Late Pennsylvanian: Kasimovian) of the adjacent Lugansk Province of the Donets Basin of Ukraine.  相似文献   

15.
Permineralised wood of Eristophyton sp. is first described from the Carboniferous deposits of the Arkhangelsk region, northern Russia. The specimens used in the study show scalariform thickening of the metaxylem tracheids both on radial and tangential walls. Eristophyton sp. indicates well preserved elements of secondary xylem: uni-, rarely biseriate xylem rays up to 15–16 cells high; uni-, multiseriate tracheid pitting only on radial walls; 1–8 contiguous cross-field pits and their inclined narrow apertures. A brief review and comparison with known anatomically preserved plants from the Lower Carboniferous of different localities of Scotland, France, USA and Poland is discussed.  相似文献   

16.
A new species and genus of Choristitinae, Adventochoristites abavus gen. et sp. nov., is described from the Upper Serpukhovian of the Donets Basin and is considered as an ancestor of the Middle-Late Carboniferous Choristites linage. The characteristic features differing Alphachoristites from Choristites and Trautscholdia are specified. New species Alphachoristites berestovensis sp. nov. and Quizhouspirifer tshaikensis sp. nov. are established.  相似文献   

17.
The shell structure of the Devonian punctate spiriferids Theodossia Nalivkin, 1925, Pyramina Ljaschenko, 1969, Warrenella Crickmay, 1953, Eoreticularia Nalivkin, 1930, Thomasaria Stainbrook, 1945 from the order Spiriferida Waagen, 1883, and also Cyrtina Davidson, 1858 and Punctospirifer North, 1920 from the order Spiriferinida Ivanova, 1972 from the Devonian and Carboniferous of the East European Platform is described.  相似文献   

18.
Marcopolia n. gen. is described from Middle Carboniferous Moscovian beds of Darwas (Tadzhikian SSR). It is the last representative of the family Thecostegidae.  相似文献   

19.
Late Palaeozoic glaciation of Gondwana affected ecosystems and caused provincialism in the earth’s biota. Periglacial seas favored the origin of endemic genera and species, and remarkable differences exist with faunas of the Palaeoequatorial realm. Carboniferous glacimarine deposits are almost everywhere associated with theLevipustula levis “cold” fauna. These bio- and lithofacies are ubiquitous along the peri-Gondwana belt that stretches from western Argentina to eastern Australia, including central Patagonia and Antarctica. Both glacial sediments and theLevipustula levis Zone are assumed to date from the beginning of the Namurian to an indeterminated part of the early Westphalian. The bivalve fauna associated with the Carboniferous glacial deposits of western Argentina is described, including four new species:Promytilus grandis n. sp.,Leptodesma (Leiopteria) aredesi n. sp.,Oriocrassatella andina n. sp., andMyofossa calingastensis n. sp. Six insufficiently preserved species are left in open nomenclature:Leptodesma (Leiopteria) n. sp.,Euchondria n. sp.,Schizodus n. sp.,Promytilus sp.,Cypricardinia? sp., andStreblopteria? sp.; it proved even impossible to decide whether a badly damaged incomplete specimen belongs toMyonia orVacunella. Five other species, which are known from single specimens, are assigned tentatively to the generaPhestia, Atomodesma, Pyramus, Vacunella, andPleurophorella.  相似文献   

20.
A pseudomonotide pelecypod-Pachypteria sinaitica n. sp. - is described from Abu Durba Formation (Visé) of southwest Sinai. The new species forms a link with rather similar populations in the Lower Carboniferous of Marocco. Like the oysters, but byssate and cemented with its right valve,P. sinaitica n. sp. built up small limestone beds within a marginal marine environment of sedimentation. As regards the isotopie composition, the carbonates of the shell were secreted in a water of approximately 25° C.It follows, that the littoral waters of the southern Tethys were warmer during the Lower Carboniferous than those of present Red Sea.  相似文献   

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