Search results for "biostratigraphy."
showing 10 items of 136 documents
A new species of Tococladidae CARPENTER, 1966 from the Permian of France (Insecta: Archaeorthoptera)
2003
Abstract A new forewing venation pattern of the Tococladidae is proposed and the phylogenetic affinities of this family are discussed, based on Tococladus garrici nov. sp. This fossil comes from the Salagou Formation (Permian, Saxonian Group, Lodeve basin, France). The Tococladidae is assigned to the Archaeorthoptera BETHOUX and NEL, 2002 . The biostratigraphic implications of this discovery are briefly discussed, but it is still not possible to infer any definite conclusion about the age of this formation.
Palaeophylloxera nov. gen., The firstfossil specimen of the family Phylloxeridae (Hemiptera, Phylloxeroidea); Lower Miocene of Spain
1999
A fossil alate aphid from the Lower Aragonian (Lower Miocene) deposits of Rubielos de Mora (Teruelprovince) in eastern Spain is described as Palaeophylloxera seilacheri nov. gen. and sp. It is the first fossil specimen described within the Family Phylloxeridae. The principal differences between this genus and other representatives of the Phylloxeridae (and also the extinct Elektraphididae) are the apparent presence of an oblique vein on the hind wing, the presence of distinctly visible transverse striae on antennal segment III, and the peculier venation on the fore wings.
THE DEMOSPONGE GENUS LEPTOMITUS and A NEW SPECIES FROM THE MIDDLE CAMBRIAN OF SPAIN
2007
Forty-five specimens of Leptomitus conicus sp. nov. have been collected from the base of the Murero Formation (Caesaraugustan, Middle Cambrian) in the Murero area of Zaragoza, north-east Spain. The new species is a small obconical sponge, which has coarse oxeas forming parallel rods that run the whole length of the specimens in the man- ner typical of the genus. The biostratigraphy and facies of the levels with Leptomitus conicus have been analysed. Palaeoeco- logical information derived from associated trilobites, brachio- pods and ichnofossils shows that L. conicus lived in a soft substrate of a sublittoral environment of low to low ⁄ moderate energy. According to established Cambrian pal…
Triassic lingulide brachiopods from the Iberian Range (Spain)
1999
Abstract During the Middle Triassic marine transgression in Spain, several lingulide populations were fossilized in the Iberian Range (western part of Sephardic Province) and the recorded specimens have been described previously under several specific names. The paleontological aspects of the Jalance (Valencia province) section have been studied for the first time. Its exceptionally large population was fossilized in situ as flat-lying valves and can be interpreted as an autochthonous association related to a very shallow marine environment. The lingulide specimens belong to the genus Lingularia Biernat & Emig , 1993 , but the species name remains under debate, probably Lingularia smirnovae…
Eomyops noeliae sp. nov., a new Eomyidae (Mammalia, Rodentia) from the Aragonian of Spain
2009
Abstract A new species of Eomyops, Eomyops noeliae, is described. from the locality MT-20A (Morteral section, Magro basin, eastern Spain). It is intermediate in size between the large eomiid, E. hebeiseni, and the small species of the group E. catalaunicus, E. bodvanus and E. oppligeri. The age range is Lower Aragonian. MT-20A is located between deposits that contain Megacricetodon primitivus and M. collongensis. Morphologically, E. noeliae sp. nov. is clearly different from the rest of species of the genus, due to an important reduction of the lingual anteroloph of M1,2,3 and the labial anterolophid of M3. The lower incisor shows two parallel ridges along the enamel like the type species o…
Chronology for the Cueva Victoria fossil site (SE Spain): Evidence for Early Pleistocene Afro-Iberian dispersals
2014
Cueva Victoria has provided remains of more than 90 species of fossil vertebrates, including a hominin phalanx, and the only specimens of the African cercopithecid Theropithecus oswaldi in Europe. To constrain the age of the vertebrate remains we used paleomagnetism, vertebrate biostratigraphy and (230)Th/U dating. Normal polarity was identified in the non-fossiliferous lowest and highest stratigraphic units (red clay and capping flowstones) while reverse polarity was found in the intermediate stratigraphic unit (fossiliferous breccia). A lower polarity change occurred during the deposition of the decalcification clay, when the cave was closed and karstification was active. A second polarit…
Cenomanian–Turonian carbonate and organic-carbon isotope records, biostratigraphy and provenance of a key section in NE Sicily, Italy: Palaeoceanogra…
2008
In eastern Sicily, a series of highly organic-rich black shales occur as exotic blocks (~ 100 m across) floating in tectonized sediments (Argille Varicolori Unit containing olistoliths of Cretaceous-Palaeogene age). A 19-metre section, through one of these blocks near the town of Novara di Sicilia, includes cyclically bedded black shales, marlstones and claystones, which have been dated using planktonic foraminiferal and nannofossil biostratigraphy. On this basis, the section is assigned to the latest Cenomanian and clearly represents a manifestation of the Oceanic Anoxic Event characteristic of that interval. Total organic-carbon values range up to 23% and the relatively high hydrogen indi…
Biocénoses à triopsidés(Crustacea, Branchiopoda) du Permien du bassin de Lodève (France)
1997
Resume Nous decrivons les triopsides (Crustacea, Branchiopoda) qui abondent dans les facies “saxoniens” de la Formation du Salagou du bassin de Lodeve date “Thuringien” ou “Saxonien” selon les auteurs. A partir de milliers de debris de carapaces, d'axes thoraco-abdominaux et plus rarement a partir d'animaux entiers, nous avons identifie et decrit deux especes nouvelles: Triops cancriformis permiensis nov. ssp. et Lepidurus occitaniacus nov. sp., morphologiquement proches d' especes actuelles. En se basant sur les preferences ecologiques des triopsides actuels et les caracteristiques sedimentologiques de leur milieu de vie au Permien, nous avons confirme l'existence d'etendues d'eau, peu pro…
Dolomitization as an eventualdetermining factor in the colour alteration index (CAI)
1993
Abstract The Colour Alteration Index of conodonts (CAI) is indicative of the degree of alteration of organic material that exists in the interior of the conodonts. This CAI is used ordinarily in the determination of paleotemperatures. More frequent findings of abnormally high CAI values, equivalent to paleotemperatures that are not compatible with temperatures obtained by other more trustworthy methods, has taken us to use values not superior to 6 for the establishment of paleotemperatures. The CAI values measured in specimens proceding from dolostones in the Iberian Range (Spain) show in this way a certain degree of incompatibility with geological data. These anomalous values are the conse…
Early Jurassic normal faulting in a carbonate extensional basin: characterization of tectonically driven platform drowning (High Atlas rift, Morocco).
2009
18 pages; International audience; This paper describes a tectonostratigraphic model of the synrift evolution of the Early Jurassic High Atlas rift of Morocco. The model is constrained by mapping of a set of inverted extensional blocks, by facies analysis of carbonate platform and turbiditic to hemipelagic synrift deposits, and by high-resolution (n 3 100 ka) biostratigraphy of the Early Jurassic succession. The chronostratigraphic packages of the High Atlas of Rich vary significantly in thickness, facies and architecture from one tectonic block to another. Our study shows how synrift strain varied in space and time over a long time interval (14 Ma) around the High Atlas rift. Initially, in …