978 resultados para Peninsula Iberica
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The aim of this paper is to quantitatively characterize the climatology of daily precipitation indices in Catalonia (northeastern Iberian Peninsula) from 1951 to 2003. This work has been performed analyzing a subset of the ETCCDI (Expert Team on Climate Change Detection and Indices) precipitation indices calculated from a new interpolated dataset of daily precipitation, namely SPAIN02, regular at 0.2° horizontal resolution (around 20 km) and from two high-quality stations: the Ebro and Fabra observatories. Using a jack-knife technique, we have found that the sampling error of the SPAIN02 regional averaged is relatively low. The trend analysis has been implemented using a Circular Block Bootstrap procedure applicable to non-normal distributions and autocorrelated series. A running trend analysis has been applied to analyze the trend persistence. No general trends at a regional scale are observed, considering the annual or the seasonal regional averaged series of all the indices for all the time windows considered. Only the consecutive dry days index (CDD) at annual scale shows a locally coherent spatial trend pattern; around 30% of the Catalonia area has experienced an increase of around 2¿3 days decade¿1. The Ebro and Fabra observatories show a similar CDD trend, mainly due to the summer contribution. Besides this, a significant decrease in total precipitation (around ¿10 mm decade¿1) and in the index "highest precipitation amount in five-day period" (RX5DAY, around ¿5 mm decade¿1), have been found in summer for the Ebro observatory.
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We present a new model to explain the origin, emplacement and stratigraphy of the Nicoya Complex in the NW part of the Nicoya Peninsula (Costa Rica) based on twenty-five years of field work, accompanied with the evolution of geochemical, vulcanological, petrological, sedimentological and paleontological paradigms. The igneous-sedimentary relation, together with radiolarian biochronology of the NW-Nicoya Peninsula is re-examined. We interpret the Nicoya Complex as a cross-section of a fragment of the Late Cretaceous Caribbean Plateau, in which the deepest levels are exposed in the NW-Nicoya Peninsula. Over 50% of the igneous rocks are intrusive (gabbros and in less proportion plagiogranites) which have a single mantle source; the remainder are basalts with a similar geochemical signature. Ar39/Ar40 radioisotopic whole rock and plagioclase ages range throughout the area from 84 to 83 Ma (Santonian) for the intrusives, and from 139 to 88 Ma (Berriasian-Turonian) for the basalts. In contrast, Mn-radiolarites that crop out in the area are older in age, Bajocian (Middle Jurassic) to Albian (middle Cretaceous). These Mn-radiolaritic blocks are set in a "matrix" of multiple gabbros and diabases intrusions. Chilled margins of magmatites, and hydrothermal baking and leaching of the radiolarites confirm the Ar39/Ar40 dating of igneous rocks being consistently younger than most of the radiolarian cherts. No Jurassic magmatic basement has been identified on the Nicoya Peninsula. We interpret the Jurassic-Cretaceous chert sediment pile to have been disrupted and detached from its original basement by multiple magmatic events that occurred during the formation of the Caribbean Plateau. Coniacian-Santonian (Late Cretaceous), Fe-rich radiolarites are largely synchronous and associated with late phases of the Plateau.
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Les restes humanes deIs períodes epipaleolític i mesolític estan pobrament representades a la Península Iberica, tot i que existeixen dos jaciments mesolítics excepcional s a Muge, Portugal (Moita do Sebastiao i Cabe~o da Arruda), amb uns 67 individus, i un altre de recentment excavat a Oliva (El Collado, Valencia), on s'han trobat uns 15 individus. EIs primers estan datats entre 7.240 i 6.300 a.P. (Ferreira 1994: 664-674), mentre que el darrer té una datació de 7.640-7.570 a.P (Aparicio 1989). Ambdós jaciments es troben en zones properes a estuaris de rius o a la costa, la qual cosa permetia 1'explotació intensiva de recursos marins molt variats. Aquest tipus d' economia condicionava un tipus de vida força sedentaria i a més a més, va permetre un increment en la densitat de població, que hauria tingut lloc probablement entre el 8.000-7.000 a.e. (Ferreira 1994: 664-674). A Catalunya, s'han excavat fins ara pocs jaciments importants d'aquests periodes (Martín y Vaquer 1995: 35-73), tots d'ells en zones d'interior i corresponents presumiblement a grups petits de caçadors-recol·lectors, força diferents dels posteriors assentaments humans més grans com Muge i Oliva. De tots aquests jaciments, només a la Balma de Guilanya (Naves, Solsones) s'han trobat restes humanes que es puguin atribuir sense cap mena de dubte als nivells epipaleolítics.
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In the Wadi Wasit area (Central Oman Mountains), Dienerian breccias are widespread. These breccias consist mostly of Guadalupian reefal blocks, often dolomitised, and some rare small-sized blocks of lowermost Triassic bivalve-bearing limestones. A unique block, with a size of about 200 m(3), including Permian and earliest Triassic faunas has been studied in detail. The so-called Wadi Wasit block consists of three major lithological units. A basal unstratified grey limestone is rich in various reef-building organisms (rugose corals, calcareous sponges, stromatoporoids) and has been dated as Middle Permian. It is disconformably overlain by well- and thin-bedded light grey to yellowish coloured limestones rich in molluscs. Two major lithologies (Coquina Limestone respectively Bioclastic Limestone unit) characterise the shelly limestones, their contact seems gradual. These two units are well-dated; they are of Griesbachian age and contain three conodont zones, the Parvus Zone, the Staeschei Zone and the Sosioensis Zone, and two ammonoid zones, the Ophiceras tibeticum Zone and an 'unnamed interval'. The third unit consists of a grey marly limestone containing Neospathodus kummeli (basal Dienerian). It is the first record of well-dated basal Triassic sediments in the Arabian Peninsula. The Coquina Limestone is dominated by the bivalve Promyalina with some Claraia and Eumorphotis. This bivalve association is interpreted as a pioneering opportunistic assemblage. Towards the top of the Bioclastic Limestone unit, the faunal diversity increases and contains probably more than 20 taxa of bivalves, microgastropods, crinoids, brachiopods, ammonoids, echinoid spines, ostracods and conodonts. The generic diversity of this biofacies exceeds by far any other Griesbachian assemblage known. Our data give new evidence for the geodynamical history for the distal carbonate shelf bordering the Hawasina Basin. A break in the sedimentation characterises the Late Permian. The basal Triassic shows a steady transgression and the breccias may record a distinct gravitational collapse of platform margins linked with sea-level low stand at the end of Induan time (late Dienerian-basal Smithian). delta(13)C(carb) isotopic analyses were performed and yield typical Permian values of around 4parts per thousand for the Reefal Limestone, with a strong negative shift across the Permian-Triassic boundary. During the Griesbachian values shift positively from 0.5 to 3.1parts per thousand parallel to an increase in faunal diversity and probably primary productivity. The detailed faunal analysis and the discovery of an unexpected diversity give,us a new understanding of the recovery of the Early Triassic marine ecosystem.
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5 poblaciones diferentes, utilizados como referencia externa en este análisis, se muestran claramente agrupados y separados de las poblaciones de G. brockmannii. En resumen, todos los dados disponibles sugieren que G. brockmannii subsp. aterratzense debe ser considerado un sinónimo de G. brockmannii.
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We examined sequence variation in the mitochondrial cytochrome b gene (1140 bp, n = 73) and control region (842-851 bp, n = 74) in the Eurasian harvest mouse (Micromys minutus (Pallas, 1771)), with samples drawn from across its range, from Western Europe to Japan. Phylogeographic analyses revealed region-specific haplotype groupings combined with overall low levels of inter-regional genetic divergence. Despite the enormous intervening distance, European and East Asian samples showed a net nucleotide divergence of only 0.36%. Based on an evolutionary rate for the cytochrome b gene of 2.4%(.)(site(.)lineage(.)million years)(-1), the initial divergence time of these populations is estimated at around 80 000 years before present. Our findings are consistent with available fossil evidence that has recorded repeated cycles of extinction and recolonization of Europe by M. minutus through the Quaternary. The molecular data further suggest that recolonization occurred from refugia in the Central to East Asian region. Japanese haplotypes of M. minutus, with the exception of those from Tsushima Is., show limited nucleotide diversity (0.15%) compared with those found on the adjacent Korean Peninsula. This finding suggests recent colonization of the Japanese Archipelago, probably around the last glacial period, followed by rapid population growth.
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The As Pontes basin (12 km2), NW Iberian Peninsula, is bounded by a double restraining bend of a dextral strike-slip fault, which is related to the western onshore end of the Pyrenean belt. Surface and subsurface data obtained from intensive coal exploration and mining in the basin since the 1960s together with additional structural and stratigraphic sequence analysis allowed us to determine the geometric relationships between tectonic structures and stratigraphic markers. The small size of the basin and the large amount of quality data make the As Pontes basin a unique natural laboratory for improving our understanding of the origin and evolution of restraining bends. The double restraining bend is the end stage of the structural evolution of a compressive underlapping stepover, where the basin was formed. During the first stage (stepover stage), which began ca. 30 Ma ago (latest Rupelian) and lasted 3.4 My, two small isolated basins bounded by thrusts and normal faults were formed. For 1.3 My, the strike-slip faults, which defined the stepover, grew towards each other until joining and forming the double restraining bend, which bounds one large As Pontes basin (transition stage). The history of the basin was controlled by the activity of the double restraining bend for a further 3.4 My (restraining bend stage) and ended in mid-Aquitanian times (ca. 22 Ma).
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abababa
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En el estudio que se viene realizando sobre la Estratigrafía del Eoceno marino de Vic hemos podido observar intercalaciones rojas entre los materiales, siempre de colores claros (azul-grisáceos, beige o blanquecinos) que constituyen las diversas facies litológicas del Eoceno marino de Vic. Su interés como facies litológicas muy diversas de las demás, su posible continentalidad y su relación con el tramo rojo intermedio del Eoceno pirenaico han hecho que les dedicáramos una atención particular.
Hydrogen isotope fractionations between amphiboles, micas, and fluids in alkaline igneous intrusions
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RÉSUMÉ DE LA THÈSE Les teneurs des amphiboles en éléments majeurs et en isotopes stables ont été analysées dans plusieurs complexes ignés alcalins et hyperalcalins, dans le but de déterminer l'importance des variations de composition des minéraux pour le fractionnement isotopique de l'hydrogène dans un système naturel minéral-magma-fluide. Cette étude se concentre principalement sur les syénites néphéliniques de complexes intrusifs alcalins bien connus mais à chimie variable, dont les amphiboles, ainsi que d'autres silicates hydratés tels que micas et eudialytes, lorsque cela était possible, ont été séparés. L'intérêt principal s'est porté sur le complexe alcalin d'Ilímaussaq de la Province du Gardar, au Sud du Groenland. Dans une optique de comparaison, nous avons collecté et analysé d'autres échantillons provenant du complexe de Tugtutôq (Sud Groenland), des complexes de Khibina et Lovozero (Péninsule de Kola, Russie), du Mont St-Hilaire et du Mont Royal (Canada) et de 6 autres du nord-ouest de la Namibie (Cape Cross, Okenyenya, Messum, Etaneno, Kalkfeld,et Okorusu). Les compositions isotopiques de l'hydrogène des amphiboles des ces différentes zones présentent de grandes variations (-227 à -700/00), ce qui est atypique pour des magmas d'origine mantellique. Les valeurs comprises entre -80 et -400/00 indiquent une provenance du manteau. Ces larges variations de compositions ainsi que l'extrême appauvrissement en isotope lourd de l'hydrogène (D), en comparaison avec d'autres roches ignées, semblent être propres.aux roches alcalines et hyperalcalines de ce type, ce qui indiquerait un processus commun. Les différents complexes alcalins choisis présentent un large intervalle de composition chimique des amphiboles. La caractérisation des amphiboles par microscopie électronique et par spectroscopie Mössbauer contribuent à observer le contrôle du Fe sur le fractionnement des isotopes de l'hydrogène. En effet, cela a mis en évidence un contrôle du Fe sur le fractionnement et même, dans le cas du complexe hyperalcalin d'Ilímaussaq, une relation entre le rapport Fei3+/FeT et les variations du rapport D/H. Les complexes étudiés diffèrent de par leur index agpaïtique (Na+K/Al) et également de par leur contenu en fer. Les plus hautes valeurs en Fe (27-35 wt%) et en éléments alcalins dans les amphiboles, ainsi que les teneurs de D/H les plus basses et leur grande variation, sont celles du complexe d'Ilímaussaq. Les amphiboles de la Péninsule de Kola et du Canada sont similaires, mais toutefois moins appauvries en D. En ce qui concerne les amphiboles des complexes du NO de la Namibie, elles présentent des compositions isotopiques de l'hydrogène magmatiques normales (-73 à -100 0/00), contiennent moins de Fe (15-17 wt%) et sont fortement enrichies en Ca et moins en Na. Dans ce cas, l'alcalinité est moins importante en comparaison des autres complexes étudiés. En dehors des teneurs en éléments alcalins des amphiboles, l'alcalinité des fluides s'avère également un facteur important, ce qui est cohérent avec certaines suggestions à partir de systèmes expérimentaux. Afin de mieux contraindre ce facteur, des expériences d'échanges hydrothermaux entre les amphiboles et les fluides de salinité différente ont été effectuées en simulant des conditions naturelles. L'approximation d'amphiboles naturelles de complexes ignés alcalins, couplée aux expériences d'échange, aide à préciser les facteurs contrôlant le fractionnement des isotopes de l'hydrogène dans les roches alcalines. Les valeurs extrêmement basses de 3D des amphiboles de ces complexes alcalins peuvent être dues à une combinaison de différents facteurs, telles qu'une haute alcalinité, une haute teneur en Fe et une faible profondeur d'intrusion. Les grandes variations ainsi que les faibles valeurs de SD des amphiboles étudiées peuvent résulter d'un processus magmatique interne et il est peu probable que de l'eau météorique soit impliquée et/ou que le dégazage magmatique ait joué un rôle. THESIS ABSTRACT Major element and stable isotope compositions of amphiboles were analyzed from a number of alkaline and peralkaline igneous complexes in order to determine the importance of compositional variations in minerals to hydrogen isotope fractionations in natural mineral-melt-fluid systems. The thesis mainly focuses on nepheline syenites of well-studied, but chemically variable alkaline intrusive rocks, from which amphiboles and, if possible, other hydrous silicates such as micas and eudialytes were separated. The system of primary interest was the alkaline Ilímaussaq Complex of the Gardar Province of South Greenland. For the purpose of comparison additional samples were collected and examined from the Tugtutôq Complex (South Greenland), the Khibina and Lovozero Complexes (Kola Peninsular, Russia), Mount St-Hilaire and Mount Royal (Canada) and six further complexes from NW Namibia (Cape Cross, Okenyenya, Messum, Etaneno, Kalkfeld, and Okorusu). The hydrogen isotope compositions of amphiboles from the localities studied differ greatly, which is atypical for amphiboles from mantle, range between - 227 and - 700/00 (latter compatible with a simple mantle origin). As this wide range in compositions and the extreme depletion in the heavy hydrogen isotope (D) content relative to other igneous rocks appear to be unique to alkaline to peralkaline rocks of this type, a common process is indicated. The different alkaline complexes chosen cover a wide range of amphibole chemical compositions. Detailed chemical characterization of amphiboles by electron microprobe and Mössbauer spectroscopy analyses helped to constrain the control of Fe on the H-isotope fractionations. Complete characterization of the chemical compositions of the amphiboles support Fe-control on fractionations and at least for the peralkaline Ilímaussaq complex a relationship between Fe3+/FeT ratios and variations in D/H. The studied complexes differ in their agpaitic index (Na+K/Al) and also in their Fe-content. The most iron (27-35 wt. %) and alkaline element rich amphiboles, with the lowermost D/H ratio, as well with very wide range, are the ones from Ilímaussaq complex. Similar, but less D depleted amphiboles are from the Kola Peninsula and the Canadian localities. The complexes described from NW Namibia have amphiboles with normal magmatic hydrogen isotope composition (-730/00 to -1000/00), and have less Fe-content (15-17 wt. %), and are more Ca-and less Na-rich. In this case alkalinity is not that important in comparison to the other studied complexes. Beside the alkaline element contents in the amphiboles, the alkalinity of the fluids has been found to be an important factor, in conjunction with earlier suggestions from experimental systems. To further constrain this factor, hydrothermal exchange experiments between amphiboles and fluids of different salinity simulating natural conditions were performed. The approach of examining natural amphiboles from alkaline igneous complexes in parallel to performing exchange experiments - helped to further constrain the factors controlling the H-isotope fractionations in alkaline rocks. The observed changes between the hydrogen and oxygen isotope compositions of amphiboles and fluids before and after the experiments suggest that another phase was produced during the experiments, which influenced the final hydrogen isotope composition of the system. This presumably hydrous phase has also influenced the Fe3 +/Fe2+ ratio of the amphiboles, which became more oxidized. The extremely low SD values of amphiboles in these alkaline complexes may be due to a combination of different factors such as high alkalinity, high Fe-content, and shallow intrusion depths. This wide range and the low SD values of the amphiboles studied might be a result of internal, magmatic processes and it is unlikely that meteoric water was involved and/or magmatic degassing played an important role. RÉSUMÉ DE LA THÈSE (pour le grand public) Fractionnement isotopique de l'hydrogène entre amphiboles, micas et fluides dans des intrusions alcalines Zsófia Wáczek Directeur de thèse, Prof. Torsten W. Vennemann Institut de Minéralogie et Géochimie, Université de Lausanne Les roches alcalines et celles qui leurs sont associées sont des sources importantes de nombreux minéraux et minerais, tels l'apatite, le niobium, le diamant et autres pierres précieuses. Cette étude se concentre sur des complexes alcalins localisés dans le sud du Groenland, au Canada, dans la péninsule de Kola en Russie et au nord-ouest de la Namibie. Ces complexes sont composés de roches ayant cristallisé à partir de magmas et de fluides très enrichis en alcalins. Cet enrichissement permet la précipitation de minéraux inhabituels riches en potassium et/ou sodium, telles les amphiboles sodiques, également enrichies en fer. Les amphiboles étudiées ont des compositions calciques, sodi-calciques et sodiques, qui reflètent leurs différents environnements de formation. Des études précédentes ont révélé une large gamme de rapports isotopiques de l'hydrogène dans les amphiboles de roches hyperalcalines, dont certains extrêmement bas. Cette variation importante est très intrigante, sachant que des valeurs entre -40 et -800/00 correspondent à des silicates ignés hydratés et non altérés, alors que des valeurs descendant jusqu'a -1500/00 nécessiteraient une altération par de l'eau météorique et/ou une contamination par les roches environnantes ou des sédiments riches en matière organique. Dans lé cas précis du complexe d'Ilímaussaq (sud du Groenland), aucune de ces explications n'a pu être démontrée et des valeurs encore plus faibles ont été trouvées. Le complexe d'Ilímaussaq présente des valeurs de rapport isotopique de l'hydrogène entre -227 et -500/00 dans les amphiboles. Une origine mantellique permet d'expliquer les valeurs élevées, mais d'autres processus doivent entrer en jeu pour engendrer les valeurs les plus négatives. C'est à l'identification de ces processus que nous nous sommes attachés dans ce travail. Les grandes variations observées dans les teneurs en fer et dans le rapport Fe3+/FeT des roches et des minéraux de ces complexes sont corrélées avec d'autres paramètres chimiques, tels que la composition isotopique de l'hydrogène dans les amphiboles. Nous avons dès lors abordé les questions suivantes: quelle est la relation entre la teneur en fer des amphiboles et leur composition isotopique? Que nous apprennent les changements de la teneur en fer et les changements dans le rapport Fe3+/FeT sur les processus pétrologiques dans ces roches? Pour répondre à ces questions, nous avons analysé les compositions isotopiques de l'oxygène et de l'hydrogène dans les amphiboles et d'autres silicates hydratés. La composition chimique et le rapport Fe3+/FeT des amphiboles ont également été déterminés. Des expériences hydrothermales simulant des conditions naturelles ont été entreprises afin de mieux comprendre les processus de fractionnement isotopiques dans ces systèmes très alcalins. Nos conclusions sont les suivantes: (1) Les valeurs extrêmement faibles ainsi que les larges variations des rapports isotopiques de l'hydrogène des amphiboles de ces complexes alcalins sont dues à une combinaison de facteurs tels que la forte alcalinité, la haute teneur en fer et la profondeur très faible de l'intrusion. (2) Ces valeurs sont probablement le résultat de processus magmatiques internes. (3) Il est peu probable que les eaux météoriques et/ou le dégazage magmatique aient joué un rôle lors de la formation de ces amphiboles. (4) Certaines corrélations, en accord avec les études précédentes, ont pu être trouvées au niveau des concentrations en fer. (5) Dans le cas du complexe d'Ilímaussaq exclusivement, une relation a été trouvée entre le rapport Fe3+/FeT et la composition isotopique de l'hydrogène des amphiboles.
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Abstract In this study, chromosomal inversion polymorphism data for a natural population of Drosophila subobscura from a swampy region near the town of Apatin (Serbia) were compared with data for the same population collected approximately 15 years earlier. The pattern of chromosomal inversion polymorphism changed over time. There were significant increases in the frequency of characteristic southern latitude ("warm" adapted) chromosomal arrangements and significant decreases in the frequency of characteristic northern latitude ("cold" adapted) chromosomal arrangements in the O and U chromosomes. The chromosomal arrangements O3+4 and O3+4+22 (derived from the O3+4 arrangement)showed significant increases in 2008 and 2009 with regard to the 1994 sample. There was also a significant increase (~50%) in the U1+2 arrangement, while U1+8+2 (a typical southern arrangement) was detected for the first time. Since the Apatin swampy population ofD. subobscura has existed for a long time in a stable habitat with high humidity that has not been changed by man our results indicate that natural selection has produced chromosomal changes in response to the increase in temperature that has occurred in the Balkan Peninsula of central southeastern European. Key words: chromosomal inversions, Drosophila subobscura, global warming, karyotypes.
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ABSTRACT: The Late Oligocene first occurrence of Miogypsina gunteri Cole and Miogypsina tani Drooger is verified in the light of larger foraminiferal assemblages from Nosara (Nicoya Peninsula, Costa Rica) and Windward (Carriacou, Grenada, Lesser Antilles). At Windward, they co-occur with planktonic foraminifera and nannofossils studied by earlier workers. 87Sr/86Sr isotope ratios were measured in calcite of larger foraminifera at both sites to determine independent absolute ages of the two outcrops. Late Oligocene shallow water formations unconformably overlie Paleocene-Eocene distal turbidites and siliceous shales in the outcrops in Costa Rica. The shallow-water lithostratigraphy includes near shore volcanic sandstones that alternate with sandy bioclastic limestones. The latter have yielded rich assemblages of larger foraminifera that have been studied in oriented sections, SEM for split material and polished rock thin sections for transmitted light and cathodoluminescence (CL) observation. The association of larger foraminifera includes Heterostegina antillea Cushman, Miogypsina tani Drooger, Miogypsina gunteri Cole, Miogypsina c.f (Miolepidocyclina) panamensis (Cushman), Miogypsina sp., Lepidocyclina (nephrolepidina) vaughani Cushman, Lepidocyclina yurnagurensis Cushman, Lepidocyclina undosa Cushman. At Windward, scattered outcrops of the Belvedere Formation expose mass flow deposits rich in larger foraminifera associated with an early late Oligocene (NP24) planktonic foraminifa assemblage. Planktonic foraminifera and nanno-fossils recovered in rocks slightly downsection indicate an upper Middle Oligocene age. Larger foraminifera species collected just north of Windward include Lepidocyclina undosa Cushman and Miogypsina gunteri Cole. The 87Sr/86Sr ratio was measured in 11 specimens of megalosphaeric Lepidocyclina spp., mechanically extracted from 2 rock samples collected at Punta Peladas (Costa Rica) Ratios range from 0.709088 to 0.708196, which correspond to a model age of 27.4 to 24.94 Ma. Very similar ratios, ranging from 0.708150 to 0.708167 were obtained from Windward Village (Carriacou). All measured 87Sr/86Sr ratios fall within a Chattian (Late Oligocene) age. Nannofossils, planktonic foraminifera and identical 87Sr/86Sr ratios from Punta Peladas and Windward clearly indicate a Chattian (Upper Oligocene) first occurrence of Miogypsina gunteri and Miogypsina tani and confirm this age range for the other larger foraminifera cited above. The first occurrence of Miogypsina gunteri in the lower Athe upper Aquitanian as proposed by European workers cannot be confirmed.
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El conocimiento de la Meseta Superior en la Antigüedad es muy desigual y obras como la presente, que sintetizan y reúnen aspectos dispersos en multitud de publicaciones, cubren un importante hueco. Por diversas causas la investigación venía atendiendo con mayor interés las etapas de cambio histórico, los pueblos prerromanos y los primeros tiempos de la implantación romana, la crisis del siglo III y su transformación posterior, etc. Se echaba en falta una obra monotemática sobre la maduración romanizadora, que indagara en los motivos de crisis que ya en ella se intuyen, durante ese siglo falsamente "anodino", es decir, el espacio de tiempo comprendido entre los años 96-198.
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Debe reconocerse que en estos años próximos al fin del milenio la publicación de estudios sobre el mundo ibérico goza de excelente salud, cuando menos en volumen. Artículos, ponencias y comunicaciones amenazan con abrumar al lector más impenitente. Por ello resulta aleccionador acudir al meritorio trabajo de Fernando Quesada: "La cultura ibérica: una aproximación bibliográfica (1992-1993)", RE/b, 1, 1994, 335-377, que reúne la producción en revistas y series no excesivamente locales -imposibles de controlar, por otro lado-, y comprobar un balance de unos doscientos títulos anuales. Ahora bien, si consideramos el número de monografías, nos situaremos en un plano selectivo, que rondará la docena al año. Diversos factores -y entre ellos la desidia de diferentes niveles administrativos y académicos- parecen confabularse para que no se disponga de un conjunto de memorias impresas proporcional al volumen de excavaciones realizadas en las dos últimas décadas.
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La publicación por Jean y Laurence Jehasse en 1973 de la obra La Nécropole préromaine d'Aléria: 1960-1968 constituyó un hito en la historia de la investigación protohistórica en el ámbito del Mediterráneo. Junto a la necrópolis de La Spina (Italia), Aléria constituyó un punto de referencia clave para el estudio de las influencias de la sociedad colonial greco-focea sobre las comunidades indígenas en Córcega y, por extensión, en el Mediterráneo occidental, así como un corpus de consulta y análisis inexcusable para la identificación de las tipologías materiales de origen griego en la esfera colonial y comercial del extremo Occidente. Recordemos que, en esa fecha, los investigadores en la península Ibérica trabajaban esencialmente a partir de las publicaciones de J.D. Beazley (que no recogían la problemática de las series peninsulares) y, muy especialmente, con la obra Las cerámicas griegas en la península 1bérica de Gloria Trías, aparecida en 1968. Cabría esperar hasta 1977, en que Marina Picazo publicó Las cerámicas áticas de Ullastret, para contar con una monografía específica de las producciones griegas en un yacimiento ibérico.