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showing 10 items of 1678 documents
Reconstruction of the internal structure of the pore system of a complex dinosaur eggshell (Megaloolithus siruguei)
2013
Despite the many reconstructions of fossil material that have recently appeared in the literature, dinosaur eggshells have never been reconstructed using computing techniques. Using the EMAC 3-D modelling methodology, we reconstruct a section of the Late Cretaceous Megaloolithus siruguei eggshell, which has a particularly complex pore system, exhibiting an intricate network of vertical, oblique, and horizontal pores.
LOCHKOVIAN TO PRAGIAN (LOWER DEVONIAN) NERITIC OSTRACODES FROM NIGÜELLA (ZARAGOZA, IBERIAN CHAINS, NE SPAIN)
2021
Lochkovian and Pragian ostracodes from the area of Niguella (Iberian Chains), which is a key area for supra-regional correlation in the Early Devonian, are described for the first time. 12 ostracode taxa from the sections Ni4 and Ni2 could be identified. The silicified ostracodes of Eifelian Ecotype are low in biodiversity, have few individuals, and are comparatively poorly preserved. Characteristic taxa of the Devonian occur. Thus, the faunas show general relations to most European Early Devonian ostracode faunas. Closer relations exist to the Eastern Guadarrama. Polyzygia kroemmelbeini LeFevre & Weyant, 1967 and P. grekoffi Weyant, 1980 are found in the basal Pragian for the first time. B…
Braquiópodos devónicos de la Cordillera Cantábrica (Norte de España). 12) Ferronirhynchia nuevo género de rinconélido (Trigonirhynchiidae) del Emsien…
2021
The taxonomic status of the subfamily Trigonirhynchiinae is discussed based on the morphological features, together with the geographic and the stratigraphic distribution of the type genus Trigonirhynchia Cooper. The new genus, Ferronirhynchia n. gen., including the type species F. pulgari n. sp., is proposed. The new taxon, close to Trigonirhynchia , occurs in upper Emsian beds of the Moniello Formation, in Asturias, serotinus/patulus conodont zones, Faunal Intervals 14 to 16a. The ontogeny and palaeoecology of F. pulgari are analyzed. Growth of the new species is bicyclic. Juvenile forms are low and biconvex displaying sharp commissures. Adult forms are high, dorsi-biconvex, ge…
Revisión de Douvillininae (Brachiopoda) de la Zona Centroibérica Meridional (Devónico Superior, España)
2021
La subfamilia Douvillininae en el Frasniense de la Zona Centroibérica meridional está representada por el género Douvillina, al que se atribuyen tres especies: Douvillina alvarezi, D. delta y D. radiata. Se propone enmendar la diagnosis del genero Douvillina que aparece en la edición revisada del Treatise on Invertebrate Paleontology (Part H, Brachiopoda), en el sentido de admitir mayor variabilidad en la convexidad de las valvas. Se discute la atribución de D. alvarezi al género así enmendado y se incorporan a la especie ejemplares estratigráficamente más jóvenes que los del material típico.
Caracterización electroquímica del proceso de degradación de materiales piritosos en colecciones geológicas y paleontológicas: propuestas de tratamie…
2020
Este trabajo analiza los problemas de conservación y tratamiento de ejemplares paleontológicos y geológicos en los museos centrándonos en ejemplares piritizados, destacando los principales factores que afectan la preservación de este tipo de colecciones. Se ha realizado una intervención en ejemplares paleontológicos y geológicos en la cual han sido tratados para su adecuada conservación. Para caracterizar el proceso de degradación se ha realizado un estudio electroquímico sobre diversos ejemplares conservados en pirita y, de este modo, poder identificar estadios de la degradación presente de los ejemplares (producida en el curso del almacenamiento y conservación). La identificación de estos…
Estratigrafía y paleontología del yacimiento QUIN-18 (Formación Valmayor, Frasniense, sinclinal de Almaden, España)
2021
n el núcleo del Sinclinal de Almadén (Ciudad Real, España) aflora una potente sucesión vulcano-sedimentaria (Complejo Vulcano-Sedimentario de Chillón), que se apoya sobre una sucesi6n esencialmente limo-pelÍtica (Fm. Yalmayor), ambas frasnienses, en el techo de esta ultima se encontr6 el yacimiento QUIN- I 8, especialmente rico en braquiópodos y ostrácodos fósiles. La edad indicada por estos correspondería a la parte alta de la Zona de Mesotaxis asymmetricus Media hasta la Zona de M. asymmetricus Superior (parte alta de la Zona de Palmatolepis punctata a la Zona de P. hassi Inferior, en la zonación estandar de conodontos).
 Los ostrácodos pertenecen al llamado ecotipo (ökotyp) eifélico…
Miocene lithological, foraminiferal and palynological data from the Belverde borehole (Portugal)
2021
XVIII Jornadas de Paleontología, 2002 Preliminary data on litho stratigraphy and biostratigraphy of the Belverde borehole (http://www. dct.Jct.unl.pt/ SondagemISondagem/colunalindex_col.html) is presented. The borehole attained 619,77 m of depth, crossing 130 m of Plio-Pleistocene and 460 m of Miocene dep osits. Main lithologies are fine sands , marl s and biocalcarenites. A coral reef was recognized in the lower part of the borehole (530-585 m). Gamma ray, neutrons and sonic diagraphies were obtained. Eight 87Sr/86Sr isotopic ages (H. Elderfield, Cambridge University)and the presence of some of the main planktonic foraminifera markers were used to establish the chronostratigraphic framewor…
"R1_SP vs. centrality (LHC10h)" of "Global polarization of $\Lambda$ and $\overline{\Lambda}$ hyperons in Pb-Pb collisions at the LHC"
2021
The correction $R_{\mathrm{SP}}^{(1)}$ for finite resolution of the spectator plane angle $\Psi_{\mathrm{SP}}$ as a function of collision centrality for LHC10h data set.
"R1_SP vs. centrality (LHC11h)" of "Global polarization of $\Lambda$ and $\overline{\Lambda}$ hyperons in Pb-Pb collisions at the LHC"
2021
The correction $R_{\mathrm{SP}}^{(1)}$ for finite resolution of the spectator plane angle $\Psi_{\mathrm{SP}}$ as a function of collision centrality for LHC11h data set.
TAXONOMY AND AFFINITIES OF AFRICAN CENOZOIC METATHERIANS
2021
The record of extinct African metatherians (Mammalia, Theria) is scanty, restricted in time (Eocene–Miocene), and its taxonomy is still subject of debate. A review of all African metatherians, or alleged metatherians, known up to now, led us to the recognition of only three taxa referable to this group: (1) Kasserinotherium tunisiense (Peradectoidea?), from the early Eocene of Tunisia; (2) Peratherium africanum (Herpetotheriidae), from the early Oligocene of Egypt and Oman, and (3) an indeterminate Herpetotheriidae? from the early Miocene of Uganda. Herpetotheriids probably reached Afro-Arabia from Europe in one or more dispersal waves since the early Oligocene. Kasserinotherium , on t…