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This paper presents new data about Early Permian (Cisuralian) strata, palynostratigraphy and absolute dating from the Copacabana Formation in central Bolivia. Recent stratigraphic and palynologic data from marine and transitional rocks at Apillapampa refine the age of Cisuralian palynomorphs in South America. Twelve samples interbedded with five volcanic ashes (processed and productive) yielded 94 palynomorph species arranged in two informal palynoassemblages: the lower assemblage Vittatina costabilis corresponds to one sample near the base of the Copacabana Formation and the upper Lueckisporites virkkiae assemblage occurs in overlying marine and coal-bearing transitional intervals. Ages were also independently refined by a modern review of conodonts, fusulinids, along with those U–Pb radiometric ages (Isotope Dilution Thermal Ionization Mass Spectrometry [ID-TIMS] of zircon-bearing interbedded tuffs). These data suggest that the lower marine member of the Copacabana Formation at this location is Asselian and Sakmarian. Lueckisporites virkkiae is a key species of palynomorph utilised in South American and global Permian biostratigraphic reconstructions. Hence, a thorough global comparison of these palynofloras and correlations is addressed in this contribution, considering first appearances of mainly cosmopolitan diagnostic taxa. Correlations are established with many similar Permian palynofloras, some also constrained with radiometric data, in South America (Brazil, Uruguay and Argentina) and elsewhere.  相似文献   
2.
A new silicified wood, Sclerospiroxylon xinjiangensis Wan, Yang et Wang nov. sp., is described from the Cisuralian (lower Permian) Hongyanchi Formation in southeast Tarlong section, Turpan City, Xinjiang Uygur Autonomous Region, northwestern China. The fossil wood is composed of pith, primary xylem and Prototaxoxylon-type secondary xylem. The pith is solid, circular, heterocellular, with sclerenchyma and parenchyma. The primary xylem is endarch to mesarch, with scalariform thickenings on tracheid walls. The secondary xylem is pycnoxylic, composed of tracheids and parenchymatous rays. Growth rings are distinct. Tracheids have mostly uniseriate, partially biseriate araucarian pitting on their radial walls. Helical thickenings are always present on both the radial and the tangential walls. Rays are 2–14 cells high, with smooth walls. There are 2 to 7, commonly 2 to 4 cupressoid pits in each cross-field. Leaf traces suggest that Sxinjiangensis nov. sp. was evergreen with a leaf retention time of at least 15 years. Based on the sedimentological evidence, growth rings within the Sxinjiangensis nov. sp. could have been caused by seasonal climatic variations, with unfavorable seasons of drought or low temperature. Low percentage of latewood in each growth ring is probably due to the intensity of climatic seasonality and/or long leaf longevity.  相似文献   
3.
Amniotes are rare in Late Carboniferous strata, especially in Europe, and despite a global diversification. They are generally more common in Lower Permian deposits. The French record around the Pennsylvanian-Cisuralian boundary is therefore re-examined. Each basin which yielded amniote remains is provided with general data on its sedimentology, stratigraphy, dating, and palaeontological content. Seven specimens are reported, of which five are synapsids and two are reptiles, each of them being a holotype. Their respective age is reassessed. The use of the regional Stephanian and Autunian stages is discussed, but their traditional sense is retained. There is currently no amniote in the Stephanian sensu stricto (= Early Gzhelian) of France. The Stephanian-Autunian Transitional Zone (= Late Gzhelian) contains the unique amniote Stereorachis blanziacensis. The Autunian sensu stricto (= Asselian) contains five, Stereorachis dominans, Haptodus baylei, Callibrachion gaudryi, Belebey augustodunensis, and Aphelosaurus lutevensis. Finally, Neosaurus cynodus can be assigned either to the Transitional Zone or to the Autunian sensu stricto. The amniote diversity increases through the Pennsylvanian-Cisuralian boundary. Despite the low number of specimens, the French record is representative of the global evolution of amniotes.  相似文献   
4.
The Permian odonatopteran Protanisoptera are discovered for the first time in the playa palaeoenvironments of Gonfaron and Lodève (Southern France). The new genus and species Bansheepteron gonfaronensis is erected and described on the basis of a distal half of a wing from the Guadalupian of Gonfaron. It is compared with all the previously described protanisopterans. Another specimen consisting of a basal half of a wing from the Guadalupian of Lodève, attributed to cf. Bansheepteron gonfaronensis, is also described. Furthermore, three new panorthopteran Caloneurodea are described from the Early to Middle Permian (Cisuralian and Guadalupian) of Southern France, viz. Gallogramma galadrieli gen. et sp. nov. from the le Luc Basin (Gonfaron, Var), and Paleuthygramma cf. acuta Carpenter, 1943 from the Lodève Basin (Hérault). These new fossils increase the palaeodiversity of the Caloneurodea, an interesting clade which now gathers six species in the red Permian of the Southern France, making it one of the most diverse clade in these palaeoenvironments after the Odonatoptera. The present discoveries better support a Guadalupian age for the Gonfaron Formation, even if a Late Cisuralian affinities remains possible.

http://zoobank.org/urn:lsid:zoobank.org:pub:1955790C-EA66-4137-9300-3E1B76C1585F

http://zoobank.org/urn:lsid:zoobank.org:act:0E77F461-6096-4567-8477-AA3D0D1037D3

http://zoobank.org/urn:lsid:zoobank.org:act:1D6DE829-BB0D-4EDA-9707-BFF442581601  相似文献   

5.
Well-preserved Marattialean fertile fronds are analyzed in this paper that come from the Cisuralian Shanxi Formation of Yongchang, Gansu Province, northwestern China. In particular, synangium in fronds and in situ spores are analyzed in the lab. Data show that the synangium of this species contains between four and five radially arranged pedicellate sporangia. The spores of this plant are small, between 21 and 30 μm, monolete and microgranulate with no visible annule. The fossils presented in this study are included within the genus Cyathocarpus. Furthermore, these spore masses and spores in situ of this genus are described in detail at the first time as a component of the Cathaysian flora. Based on comparisons with previously reported fossil records of these plants, we determined a series of differences. Thus, the fossils presented here are referred to a new species. In addition, the reproductive organs of the new fossils described in this paper provide some valuable taxonomic information. Based on the paleogeographic distribution of Cyathocarpus and the position of paleoplates in Late Paleozoic, we speculated that one of the possible migrated routes of Cyathocarpus is from the Euramerica to the North China Block and Alashan Terrane, terminating in the South China Block.  相似文献   
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