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1.
Wright, A.J., Plusquellec, Y. &; Gourvennec, R., February 2016. Devonian operculate corals (Calceolidae, Cnidaria) from the Massif Armoricain, France. Alcheringa 40, xxx–xxx. ISSN 0311-5518

The operculate coral Calceola gervillei Bayle, 1878 Bayle, E., 1878. Fossiles principaux des terrains de la France. Explication de la Carte Géologique de France 4(1), 1158. [Google Scholar] is described for the first time on the basis of the type material from the Cotentin region of Normandy (North Armorican Domain), from Early Devonian (likely upper Lochkovian to lower Pragian) strata, and is chosen as the type species of the monotypic new genus Gerviphyllum. The new genus is also present in the l’Armorique Formation (lower Pragian) of the Plougastel Peninsula (Central Armorican Domain) as Gerviphyllum sp. cf. G. gervillei. One locality in the upper Emsian (Polygnathus serotinus Conodont Zone) Le Fret Formation, on the northern coast of the Crozon Peninsula, has yielded operculate coral specimens described here as ?Chakeola sp., the first (tentative) record of the genus outside eastern Australia, south China and Vietnam. The operculate coral Calceola collini sp. nov. is described from six localities in the early Middle Devonian (Eifelian: Polygnathus costatus Conodont Zone) Saint-Fiacre Formation of the Plougastel and Crozon Peninsulas (Central Armorican Domain), despite the fact that knowledge of the internal characters, especially of the operculum, of the type species Calceola sandalina is very limited. From an extensive review of published references to Calceola from France, we conclude that only the record of Collin (1929 Collin, L., 1929. Un nouveau gisement à calcéoles dans le Dévonien de la Presqu’île de Crozon (Finistère). Bulletin de la Société Géologique et Minéralogique de Bretagne 7(3/4), 201208. [Google Scholar]) is valid.

Anthony Wright (), GeoQuEST Research Centre, School of Earth &; Environmental Sciences, University of Wollongong, Wollongong, NSW, 2522, Australia; Yves Plusquellec () and Rémy Gourvennec (), Université de Bretagne Occidentale, CNRS-UMR 6538 ‘Domaines océaniques’, Laboratoire de Paléontologie, UFR Sciences et Techniques, 6 avenue Le Gorgeu, CS 98837, F-29283, Brest, France. Received 1.10.2015; revised 8.12.2015; accepted 14.12.2015.  相似文献   

2.
Loess is an aeolian Pleistocene sediment of periglacial or arid origins, deposited without internal stratification in parcels representing geological periods. The contents of total as well as individual carbonates are comparatively uniform within a specific stratum, but the relative carbonate contents differ significantly between the various glacials as represented by loess facies. There is a consistent increase in the content of dolomite with decreasing age of stratigraphic units, which has traditionally been attributed to postdepositional alteration, notably the gradual removal of the calcite fraction by weathering. The explanation of pedogenetic enrichment in the course of aeolian recycling of glacial and glacio-fluvial deposits could convincingly account for the stepped profile of the dolomite's depth functions. The implication is that such recycled sediments can be attributed to specific cryocratic phases simply by their characteristic dolomite fraction, i.e. they can be dated. In order to test this hypothesis against the competing weathering hypothesis, strata of the Gudenus Cave in Lower Austria were subjected to carbonate differentiation analysis. The results are presented, analyzed and discussed. It is shown that the dolomite contents of the unweathered strata provide a clear trend that is even more pronounced than that found at open-air sites.  相似文献   

3.
Wang, G., Percival, I.G. & Li, R., 25.2.2015. Remarks on the pattern of septal insertion in rugose corals. Alcheringa 39, xxx–xxx. ISSN 0311-5518

Well-preserved specimens of the Hirnantian (latest Ordovician) rugose coral Lambeophyllum? corniculum He from the Yangtze Platform of South China, clearly show how catasepta (minor septa) are inserted, confirming the model proposed by Weyer in the 1970s. Our observations indicate the insertion of counter lateral septa and their neighbouring catasepta on the counter side takes place in exactly the same manner as that of the subsequent metasepta and catasepta. We propose abandoning the use of the term counter lateral septa. Therefore, exclusion of the pair of counter lateral septa reduces the number of protosepta from six to four.

Guangxu Wang [], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (CAS), 39 East Beijing Road, Nanjing 210008, PR China; Ian G. Percival [], Geological Survey of New South Wales, 947953 Londonderry Road, Londonderry, NSW 2753, Australia; Rongyu Li [], Department of Geology, Brandon University, Manitoba R7A 6A9, Canada.  相似文献   

4.
Jell, P.A., 2013. Placocystella in the Early Devonian (Lochkovian) of central Victoria. Alcheringa, 567–569. ISSN 0311–5518.

The South African allanicytidiid mitrate carpoid Placocystella africana (Reed) is recorded for the first time from Australasia having been collected from a Lochkovian bed of the Humevale Formation at Mooroolbark in eastern Melbourne. The Southern Hemisphere Allanicytidiidae incorporating five monospecific genera in Brazil, South Africa, Tasmania, Victoria and New Zealand is now known to have a species in common between South Africa and Victoria. The previously suggested synonymy of these five is revised to accept Placocystella, Tasmanicytidium, Allanicytidium and Australocystis (but not Notocarpos) as synonymous so that the family contains Placocystella with four species and monospecific Notocarpos.

Peter A. Jell [p.jell@uq.edu.au], School of Earth Sciences, The University of Queensland, St Lucia Queensland 4072, Australia. Received 10.4.2013; revised 6.6.2013; accepted 17.6.2013.  相似文献   

5.
A single eurypterid (Arthropoda: Chelicerata) chelicera, assigned to Acutiramus sp. cf. A. bohemicus, is described from the Wilson Creek Shale, Turtons Creek inlier, north of Foster, Victoria, Australia. The specimen comprises the proximal portion of both rami. This pterygotid chelicera supports an Early Devonian (?Lochkovian) age for the stratum at this locality, by comparison with occurrences of A. bohemicus from the Czech Republic and closely related species in northern Gondwana.  相似文献   

6.
7.
J. M. SHARP JR    M. SHI 《Geofluids》2009,9(4):263-274
Although studies of free convection commonly focus on highly permeable strata, but numerical analyses indicate that density-driven free convection may also occur in heterogeneous low-permeability strata. Traditional Rayleigh number criteria are overly conservative in predicting thermohaline convection in these systems; so, numerical models are used to make inferences on the process. Simulations with stochastic realizations of permeability fields show that dense plumes can take preferential pathways to sink through generally low-permeability strata; patch analysis using percolation theory shows that the threshold permeability for the onset of free convection can be as low as 10−16 m2 even with a mean permeability of 10−18 m2. Threshold permeability for the percolation pathways decreases with increasing concentration gradient, vertical correlation length and the mean and variance of the permeability. The connectedness of relatively high-permeability zones is important in initiating and controlling plume fingers of free convection in both single-layer and sand-shale sequence models. Permeable units above and below are conducive to free convection through intervening low-permeability strata if buoyancy gradients exist. This heterogeneity is on scales that are difficult to sample by drilling and too localized to be simulated in regional models but may be significant in solute transport in these systems.  相似文献   

8.
方金友 《安徽史学》2010,(3):109-114
社会阶级阶层的分析与研究,一直是每个国家、地区在进行社会建设过程中制定路线、方针和政策的重要依据。建国以来,安徽社会和全国一样,经历了两次重大制度变革。随着经济发展,在经济结构、产业结构调整的同时,安徽的社会阶级阶层结构发生了深刻的演化,有些阶层分化了,有些阶层新生了,有些阶层的社会地位提高了,有些阶层的社会地位下降了。进入21世纪,安徽各个社会阶层之间的经济、政治关系发生了并且还在继续发生各种各样的变化,正在向与现代经济结构相适应的现代社会阶层结构方向转变。  相似文献   

9.
A locality in the Late Devonian Cloghnan Shale (Nangar Subgroup) near Forbes, N.S.W., has yielded a rich vertebrate fauna including the antiarchs Bothriolepis and Remigolepis, the phyllolepid Phyllolepis, the dipnoan Soederberghia, and the jaw of a new ichthyostegaliid amphibian Metaxygnathus denticulus gen. et sp. nov. The amphibian is the oldest known member of the group with the possible exception of Elpistostege Westoll, and it retains characters previously associated with the rhipidistian fishes. The musculatures of rhipidistian and amphibian jaws are analysed and are shown to be functionally related to distinctive morphologies of the articulatory region in each group, Metaxygnathus being of amphibian type. Comparison is made with the Greenland ichthyostegids, and rhipidistians such as Eusthenodon.  相似文献   

10.
A spectacular association between a chaetetid, a stromatoporoid (Salairella sp.), and straight, vertical tubes interpreted to have housed symbiotic worms is reported from the Givetian Burdekin Formation, Burdekin Basin, north Queensland. The final growth surface of Salairella sp. shows skeletal distortion characterised by long, rather continuous coenosteles and coenostroms with upturned edges. This distorted interface was probably the result of spatial competitive interaction between the encrusting chaetetid and the underlying stromatoporoid. Neither sediment infilling, erosion or surface breakage occurs on the final growth surface of the stromatoporoid skeleton. As such, the growth of the Salairella sp. specimen appears to have been supressed by the encrusting chaetetid. Worm tubes are continuous through the distorted interface without interruption. The skeletal association also suggests that the round, straight, vertical tubes had a symbiotic intergrowth relationship initially with the stromatoporoid and, subsequently, the chaetetid.  相似文献   

11.
The discovery of two new Frasnian species of the subfamily Asteropyginae, Bradocryphaeus kermanensis and Radiopyge hamedii, in the Haruz section north of Kerman, east-central Iran, demonstrates for the first time the presence of North Gondwanan trilobites in this region. The two new species provide a link between faunas from Afghanistan to the east and the Alborz Mountains in north Iran. The recognition of R. hamedii confirms the validity of Radiopyge Farsan, hitherto known only from Afghanistan, as well as the presence in some Frasnian Asteropyginae of six pairs of lateral pygidial spines.  相似文献   

12.
Edgecombe, G.D. March 2007. Acaste (Trilobita: Phacopina) from the Early Devonian of Tasmania. Alcheringa 31, 59-66. ISSN 0311-5518.

The widespread Siluro-Devonian acastid trilobites Acaste and Acastella are known from few occurrences in Australasia, these being confined to Lochkovian strata in Victoria and New Zealand. A new species, Acaste andersoni, is described from a correlative of the Bell Shale near St Valentines Peak in north-western Tasmania. Acaste supplements the biogeographic links between the Early Devonian faunas of New Zealand, Victoria and Tasmania.

Gregory D. Edgecombe [greged@austmus.gov.au], Australian Museum, 6 College Street, Sydney, NSW 2010, Australia; received 2.3.2005, revised 6.4.2005.  相似文献   

13.
A skull of a young specimen of Dipnorhynchus sussmilchi (Etheridge Jr), from the base of the Bloomfield Limestone Member (mid-Emsian, probably perbonus Zone) at Taemas, has both sides of the skull roof preserved, but the cheeks are missing. The posterior end of the endocranium, up to its dorsal extremity, provides new data on the endolymphatic sacs, and the attachment of the epaxial muscles. The endolymphatic region is compared with that of Chirodipterus australis. The palate is not fully formed and the marginal ridges are not fully developed. The fine structures around the dermopalatines and the pterygoids are preserved, indicating the manner in which the plates grew. The position of the parasphenoid is clearly outlined against the pterygoids, and confirms the view that this primitive genus of dipnoans did not have the pterygoids divided by the parasphenoid. All these features provide new information and comparison with Dipterus valenciennesi, the next oldest genus on which the same regions are preserved. In addition, a new mandible from a horizon low in the Cavan Bluff Formation is well preserved and provides information on the external bones of Dipnorhynchus.  相似文献   

14.
This paper reports the discovery of three of the most iconic New Caledonian endemic genera, Amphorogyne, Paracryphia and Phelline, as dispersed leaf cuticle fossils in the early Miocene of New Zealand. New Caledonia's endemic angiosperm families have given it a reputation as one of the most interesting botanical regions in the world, but unfortunately it has no known pre-Pleistocene Cenozoic plant fossil record. A once more widespread distribution of its key plants in the context of a cooling and drying Neogene world suggests the current vegetation of New Caledonia is the result of contraction, or even a migration, from more southerly landmasses. Thus, New Zealand may have been a source of at least some of New Caledonia's plants.  相似文献   

15.
Thelodont scales and associated fragments of conodont elements identified as Turinia sp. cf. Turinia australiensis and Ozarkodina sp. cf. Ozarkodina buchanensis respectively are described for the first time from the Early Devonian Murray Creek Formation of Reefton, New Zealand. The conodont and thelodont components of the fauna suggest a late Pragian to early Emsian age for the assemblage.  相似文献   

16.
Plusquellec, Y. &; Wright, A.J., October 2017. Revision of the Early Devonian tabulate coral Pleurodictyum bifidum from New South Wales. Alcheringa 41, xxx–xxx. ISSN 0311-5518.

The tabulate coral Pleurodictyum bifidum Jones, 1944 Jones, O.A., 1944. Tabulata and Heliolitida from the Wellington district, N.S.W. Journal and Proceedings of the Royal Society of New South Wales 77, 3339. [Google Scholar], from the Early Devonian (Pragian or lower Emsian) Garra Formation of central New South Wales, Australia is revised on the basis of the holotype and three other specimens. It is selected as the type species of the new monotypic genus Bifidomeria (Family Roemeriidae), which differs from Roemeria in its strictly cerioid corallum, its bifid septal spines and aspects of its microstructure. Study of the detailed microstructure of two other tabulate corals from the Devonian of New South Wales has led to the following revised generic assignments: Michelinia progenitor Chapman, 1921 Chapman, F., 1921. New or little known fossils in the National Museum. Part XXV—some Silurian tabulate corals. Proceedings of the Royal Society of Victoria 33, 212225. [Google Scholar], previously assigned to Roemeripora, is assigned to Roemeria, and Holacanthopora clarkei Wright &; Flory, 1980 Wright, A.J. &; Flory, R.A., 1980. A new Early Devonian tabulate coral from the Mount Frome Limestone, near Mudgee, New South Wales. Proceedings of the Linnean Society of New South Wales 104, 211219. [Google Scholar] is assigned to Michelinia.

Yves Plusquellec [], Université de Bretagne Occidentale, CNRS-UMR 6538 ‘Domaines océaniques’, Laboratoire de Paléontologie, UFR Sciences et Techniques, 6 avenue Le Gorgeu, CS 98837, F-29283 Brest, France; Anthony Wright [], GeoQuEST Research Centre, School of Earth &; Environmental Sciences, University of Wollongong, Wollongong NSW 2522, Australia.  相似文献   

17.
The modern history of collection and study of corals in the Permian strata of Timor began in 1911,with a German expedition (J.Wanner, leader) and a Dutch expedition (H. Molengraaff, leader) to collect Permian and Triassic fossils in the colony of Netherlands Timor, and with a survey by the Swiss geologist F. Weber the same year in Portuguese Timor, the eastern portion of the island. Later expeditions led by Jonker (1916) and Brouwer (1937), both of the Netherlands, greatly increased already huge collections of fossils and additionally, understanding of the island's geology. Monographic studies of these coral collections by Gerth (1921), Koker (1924), Schindewolf (1942), Hehenwarter (1951) and Schouppé & Stacul (1955, 1959) have much enhanced the systematic value of these fossil corals, both Rugosa and Tabulata. Locality information and maps containing collecting localities are somewhat scattered (Wanner 1931, Burck 1923, Marez Oyens 1940, Van Bemmelen 1949), but are summarized here. A list of all valid species names(109 Rugosa, 25 Tabulata) is appended to this paper, with type localities and horizon. Serious problems of nomenclature are avoided in this paper by accepting genus names used in Hill (1981), modified by later systematic studies, such as that of Fedorowski (1986), but some unknown number of names in the list of species are to be synonymized, especially since 31 of them are based on a single specimen (e.g. Niermann 1975). The biostratigraphy of these faunas is uncertain, in great part due to the greatest number of corals having been collected from a tectonic mélange sequence in the Baun to Basleo structural region, and additionally because of the purchase of huge numbers of fossils from the indigenous people of Timor, with accompanying uncertainties regarding locality and horizon data. The coral fauna of Permian age from Timor needs serious restudy to insure its stratigraphic and palaeontologic value, but future study will require new field collection of specimens from the relatively complete stratigraphic sequences in the northern ‘Fatu’ belt of outcrops. The huge numbers of individuals of some coral species provide great opportunities for understanding population structure in these faunas.  相似文献   

18.
Parexus Agassiz was one of the first Early Devonian ‘spiny sharks’ to be described. The genus is readily recognized by the large size and ornament of its anterior dorsal fin spine. Although two species were erected, reappraisal of all known specimens indicate they should be synonymized in the type species Parexus recurvus. Farnellia tuberculata Traquair, originally described as a vertebral column, is actually tooth rows of jaw dentition, and is also now considered to be a junior synonym of P. recurvus. Parexus has a perichondrally ossified scapulocoracoid of typical acanthodian shape, and diagnostic features of the family Climatiidae, but has distinctive scales comprising appositional growth zones that closely resemble those of the putative stem chondrichthyan Seretolepis elegans Karatajute-Talimaa.  相似文献   

19.
20.
Wang, B. & Gai, Z.K., 2014. A sea scorpion claw from the Lower Devonian of China (Chelicerata: Eurypterida). Alcheringa 38, XXXX. ISSN 0311–5518.

An isolated chelicera (claw) of a pterygotid eurypterid is described from the Lower Devonian Xitun Formation of Yunnan Province, China. It is different from chelicerae of other pterygotids in having four principal denticles and at least four intermediate denticles between the principal denticles on both rami. This Chinese pterygotid, estimated at about 70 cm long, was a top predator that probably hunted small, primitive fishes, such as galeaspids. This discovery represents the first record of Pterygotidae from Asia and the third fossil eurypterid from China.

Bo Wang (corresponding author) [], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China; Steinmann Institute, University of Bonn, 53115 Bonn, Germany; Zhikun Gai [], Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China. Received 22.10.2013, revised 15.11.2013, accepted 20.11.2013.  相似文献   

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