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1.
The mines exploiting the Cenomanian lignites at Simeyrols (Dordogne, France) were long known in geological terms. The presence of amber had been occasionally reported. Recent investigations have helped to collect material from cuttings of the old exploitations that provided amber beads of small size. The grains have mostly a teardrop shape more or less elongated and appear translucent. The opaque parts of the grains correspond to colonization of filamentous microorganisms that will be further studied.  相似文献   

2.
The “Megalosaur” remains from Saint-Agnant (Charente-Maritime, France), reported as early as 1881 by Boissellier, are here described and figured for the first time. These bones, as well as a few additional specimens from the nearby locality of Soubise, belong in fact to an indeterminate sauropod. The stratigraphical position of these remains unambiguously indicates an infra-Cenomanian age. However, the presence in this area of continental deposits with Purbeckian and Wealden facies does not allow to decide between an earliest or late Early Cretaceous age.  相似文献   

3.
Nodules of fossil resin or amber, first drifted and then deposited in the marine series with cephalopods, were discovered in several areas of High-Provence, in geological series of the Cretaceous system. These areas are located around the Mountain of Lure; amber nodules have been found in the upper Albian (Ongles, Revest-des-Brousses) and in the lower Cenomanian (Saint-Étienne-les-Orgues, Aubignosc and Salignac). These ambers have very homogeneous and characteristic FTIR spectra, making it possible to distinguish them not only from more recent ambers of the upper Cretaceous of Provence (Santonian), but also from tertiary ambers of the Baltic sea. These organic matters in marine environment, brought by the currents and deposited in shallow waters of the Ventoux-Lure area, are in agreement with close emerged grounds, which were set up by the Albo-Cenomanian tectonic movements.  相似文献   

4.
Ostracode assemblages, collected in the continental “Red Beds” of the Central High Atlas, Morocco, consist of 35 species, belonging to 17 genera, four of which are new and described herein. They allow to assign the lower member of the Iouaridène formation to the Upper Jurassic (?)-Upper Hauterivian and the Jbel Sidal formation to the Upper Hauterivian-Lower Aptian. Ostracode assemblages characterize lacustrine (freshwater) and lagoonal (oligo to mesohaline) environments. On the basis of limnic and lagoonal species, faunal connections are proposed for the Barremian-Aptian between Morocco and the Iberian Peninsula.  相似文献   

5.
Millimetric amber grains associated with lignite debris were recently reported in the Santonian marine series from Belcodène (Bouches-du-Rhône, France). These are mainly yellow to reddish drop-shaped grains, more or less transparent. They reveal the presence of various microorganisms, belonging to prokaryotes (bacteria, actinomycetes) and eukaryotes (filamentous fungi) here described for the first time. These microorganisms form sometimes crusts around the amber grains and grew centripetally into the ancient resin before its solidification. The depositional environment of amber was open to marine influences, while the original environment of resin flow was a coastal forest with dominant angiosperms.  相似文献   

6.
The revision of the Crioceras puzosianum d’Orbigny, 1842 made during the revision of the Paléontologie Française of d’Orbigny, shows that this taxon belongs to a new genus: Anglesites gen. nov. This new genus, from upper Barremian age, is monospecific for the moment and is homeomorphic to the Leptoceratoides from the Lower Barremian. It is temporarily included in the subfamily of the Leptoceratoidinae. A neotype for the “Crioceraspuzosianum d’Orbigny, 1842 is herein designated.  相似文献   

7.
The Ecouflant area (Maine-et-Loire, France) shows the last outcrops from the Anjou region that allow the study of early Cenomanian lignites and the associated amber. The quarry of Le Brouillard was historically the most studied locality, but it is now partly covered by bulky waste. No fossil arthropod has been found in the amber collected in this locality, and only a few bacterial filaments and plant fragments were detected among the microinclusions. The quarry of Hucheloup shows a wider exposure. Amber is poor, but fossil plants and bivalve are frequent. Based on the sedimentological series and the palaeontological contents of the lignitic clay, we suggest that it corresponds to estuarine to coastal depositional environments with variable salinity.  相似文献   

8.
The recent discoveries of remarkably preserved specimens of Imerites dichotomum (Ammonoidea, Ancyloceratina) bring new palaeontological precisions on this genus. The study of the ontogenic development demonstrates that Imerites directly derives from genus Pseudoshasticrioceras. So, their origin is within the Gassendiceratinae and not in the Heteroceratidae like it was usually admitted. On the other hand, the coexistence of macroconch and microconch specimens in the species of the genus Imerites confirms the hypothesis of a dimorphism. The new palaeontological data prove that “Crioceras” cristatus is a nomen dubium and must be abandoned.  相似文献   

9.
A layer of clay interbedded in sandstone, which age is likely uppermost Albian, yielded a new deposit with amber and fossil plants in Charente-Maritime (south-west France). A survey of the arthropods found in amber, the xylologic and palynologic determinations and the sedimentologic study are in progress. We already have datas to propose a palaeoenvironmental reconstruction of the coast of the northern Aquitain basin at the end of lower Cretaceous : an estuarine area under warm and wet climate.  相似文献   

10.
This work is mainly an answer to the work of Bert, Delanoy and Canut, on the genus Imerites Rouchadzé, and we add also some points to the knowledge of this genus. An answer is given for the implication of one of the authors (J.V.) of this present work, about the origin of the genus Imerites Rouchadzé, and some significant bibliographic references, not named in the 2009 work, are specified and placed in their context. The characteristics of the ornamental stage “Pseudoshasticrioceras” mainly defined by an oval and compressed section of the whorls and by regular ventrolateral clavi, well marked, which frame the venter in a typical way (Bert et al., p. 181), don’t allow to affirm the presence of this stage during the ontogeny of all species of the genus Imerites Rouchadzé, contrary to what Bert, Delanoy and Canut (p. 30, 31) wrote. The type-species of the genus Imerites Rouchadzé is made clear by the application of the rules of the I.C.Z.N. code. The article 23, with the paragraph 23.1 of the I.C.Z.N. code, imply the senior synonymy of Imerites cristatus (Orbigny) on Imerites giraudi (Kilian), even if the Kilian's species is still the type species of the genus Imerites Rouchadzé. The taxinomical validity of the species Imerites cristatus (Orbigny) is confirmed. Its morphological variability is clarified by the distinction of four referential morphotypes, Cristatus, Giraudi, Favrei and Raricostatum. Consequently, the assumption of a shape-dimensional dimorphism into the populations of the genus Imerites Rouchadzé is rejected, awaiting irrefutable proof. A new species, Imerites stephaniae sp. nov., is described. It was collected in the Gerhardtia sartousiana Zone, in the uppermost part of the Gerhardtia provincialis Subzone, and it is a probable ancestor of the cogeneric species of the Imerites giraudi Zone.  相似文献   

11.
In the volume IV of the “Paléontologiefrançaise”, A. d’Orbigny deals in particular with Cretaceous rudists. Numerous type specimens of Hippuritidae, Caprinidae, Radiolitidae, Caprotinidae, Requieniidae belonging to his collection and deposited in the Muséumnationald’histoirenaturelle, Paris. Among the 78 species that he has studied, A. d’Orbigny introduced 41 as new ones. This review presents a picture of all types with a comment on the original definition, and set the statute, and the precise stratigraphical level of illustrated forms. The present work gives rise to the designation of 40 lectotypes, two syntypes and three neotypes.  相似文献   

12.
Many specimens of non-marine Ostracodes, especially the new species Zonocypris digitalis were recovered from continental deposits of fuvelian (Campanian) age at Auriol (Provence, south-east France). First species of that genus described in the Cretaceous of southern Europe, Z. digitalis is associated with Charophytes and mainly Gastropodes remains, thus providing confirmation of the datation proposed and age of the studied outcrops. Z. digitalis may be integrated within the current biostratigraphic scale which is accepted as valid for the non-marine Upper Cretaceous of the above mentioned area.  相似文献   

13.
Found in Chiapas (South-East of Mexico), Praealveolina michaudi nov. sp. and Chubbina jamaicensis (of Campanian-Maestrichtian age) are described, both evolved from Nummoloculina sp. while Raadshoovenia guatemalensis (upper Paleocene-lower Eocene) arises from Quinqueloculina. We precisely analyze and modelize the nepionic coiling during the evolutionary change from Miliolacea to Alveolinacea. During ontogenesis as well as during phylogenesis, quinqueloculine coiling progresses to streptospiral and then to planispiral chamber arrangement with the increase of volume of embryo and of chambers. Appearance of these large foraminifers are understood as a consequence of the rise of K-strategies in their mode of life, following the development of photosynthetic symbioses.  相似文献   

14.
A Belouze  C Atallah 《Geobios》2003,36(3):241-273
New specimens from Cenomanian outcrops of Lebanon permit redescribtion of the first eel-like fossil fishes. Anguillavus bathshebaeHay, 1903 becomes synonymous with the type species A. quadripinnisHay, 1903. A new fossil eel with pelvic fins, Anguillavus mazeni nov. sp., is furthermore proposed. In the same way, the revision of Luenchelys minimus nov. gen., nov. sp., reveals some morphological variations at the specific level and a widespread biogeographical repartition which potentially can be important. This whole anatomical revision is a necessary basis for integrating these fossils into the Anguilliformes (Teleostei, Elopomorpha) and gives an idea of the plesiomorphic structural pattern of the order, in which the modern forms are particularly specialised.  相似文献   

15.
In several synclines of the central High Atlas, the “Redbeds” following the closure of the marine Tethyan Atlasic trough during the Middle Jurassic are constituted by three successive formations or units of continental deposits dated recently with biostratigraphical elements. Some micropaleontological markers, mainly charophytes and ostracods, allow to precise the stratigraphy in agreement with a Bathonian-?Callovian assignment for the lower unit (Guettioua Formation), and in dating the middle and upper units. The Upper Jurassic, mainly the Kimmeridgian, is developed in the lower part of the middle unit (Iouaridene Formation). The Barremian has been recognized in this middle unit and in the upper unit (Jbel Sidal Formation). The Jurassic/Cretaceous boundary is thus delimited for the first time with micropaleontological data. These new data are very significant for the Atlasic history during the Mesozoic. The basaltic flows inserted in the continental Jurassic-Cretaceous deposits of the central High Atlas result from two separate events in the Middle Jurassic and in the Barremian. The tectogenesis in the basins is characterized by a polyphase process including notably a synsedimentary tectonic activity conspicuous in the Barremian. The evidence of marine to brackish intercalations allows moreover to date the first Cretaceous transgressive event on the NW boundary of the High Atlas during the Lower Barremian and to consider an Atlantic paleogeographical interaction. SW margin of the Tethyan trough in the Lower and Middle Jurassic, the central High Atlas is merged with the margin of the central Atlantic Ocean during the Lower Cretaceous.  相似文献   

16.
L Taverne 《Geobios》2002,35(5):605
The osteology of Pseudanogmius maiseyi gen. and sp. nov., a marine teleost of the Upper Cretaceous of Kansas, is studied. This fish belongs to the order Tselfatiiformes and more particularly to the group with a more or less flat skull roof and with large, quadrangular and joined parietals. Pseudanogmius maiseyi, formerly named Anogmius sp. by Hay (1903), differs from Bananogmius and the other genera known in the order by three autapomorphies: an elongated and very narrow vomer, a peculiar relief of the toothed part of the parasphenoid, and transverse processes on the caudal vertebrae. Within the order, it shows a few evolved characters, such as the loss of the preural 1 hemal arch and of the sixth autogenous hypural and by the shortening of the preural 1 neural spine.  相似文献   

17.
A microfauna composed of 11 species of ostracodes belonging to 11 genera have been recovered from the Bhanness Formation of Kimmeridgian age, in Central Lebanon. Four species are new and are described herein: Ektyphocythere dahressawanensis nov. sp., Dicrorygma (Orthorygma) libanensis nov. sp., Citrella? elongata nov. sp. and Procytherura inflata nov. sp. From a palaeobiogeographical standpoint, this fauna characterizes the North Gondwana province which differs from the South Gondwana province, particularly by the presence of the genus Schuleridea and the absence of the genus Majungaella.  相似文献   

18.
An association of limnic ostracodes has been discovered in the upper part of the Irbzer Formation, of Maastrichtian age, in the Moroccan Middle-Atlas. A new species is described, Gomphocythere achloujensis nov. sp. Paracandona occitanica, which is very common in terminal Cretaceous non-marine deposits of southern Europe (France, Spain), is found for the first time on the south Tethyan margin.  相似文献   

19.
The rich echinoid fauna from the Lower Cretaceous of the Agadir, Haha and Essaouira basins has been revised taxonomically, based on new and abundant collections. Forty-seven species have been identified, of which 20 are reported for the first time from this region and a further three represent new species left in open nomenclature. Their stratigraphic ranges have been determined accurately by reference to the regional ammonite zonation. However, it is also possible to use a local biostratigraphical scheme based on the echinoid succession, where ammonites are rare. The Toxasteridae, which are very abundant and underwent rapid evolution, are the most useful biostratigraphically. The genus Toxaster appears in the Lower Berriasian and continues until the Gargasian passing through the following succession: T. africanus, T. granosus, T. kiliani, T. lorioli, T. obtusus, T. exilis, T. retusus, T. maurus, T. peroni, T. collegnoi. The presence of Eoholaster, Macraster, Douvillaster, Palhemiaster, Heteraster and Pygopyrina is signaled for the first time in the Atlantic High Atlas region.  相似文献   

20.
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