Linking Palaeozoic palaeogeography of the Betic Cordillera to the Variscan Iberian Massif: new insight through the first conodonts of the Nevado-Filábride Complex

International Journal of Earth Sciences - Graphite-rich metamorphic limestones included within low-grade black schists of the lowest Nevado-Filábride tectonic unit in the Sierra de Baza...     

Arabia Terra,Mars: Tectonic and Palaeoclimatic Evolution of a Remarkable Sector of Martian Lithosphere

A regional geologic study of Arabia Terra, a densely cratered area of Mars northern hemisphere, has revealed the individuality of this province. This is best expressed by an equatorial belt with a crater age distinctly younger as compared to the northern part of Arabia Terra and to Noachis Terra to the south. We interpret this as an incipient back-arc system provoked by the subduction of Mars lowlands under Arabia Terra during Noachian times. The regional fracture patterns are also best explained in this manner, making it unnecessary to appeal to a rotational instability of the planet, which is not supported by the palaeoclimatic indicators in the area. This model could be the first regional-scale confirmation of Sleep's (1994) hypothesis of a limited plate consumption as an explanation of the martian dichotomy. This revised version was published online in July 2006 with corrections to the Cover Date.     

Effects of weather types on hospital admissions for respiratory diseases in Castilla-La Mancha,Spain

The aim of this study is to evaluate the relationship between the risk of hospital admission for respiratory diseases (RD) and the daily weather types during the period 2000-2006. A synoptic climatological approach is used to investigate links between air-mass types (weather situations) and all respiratory hospital admissions in the Castilla-La Mancha (CLM) area in Spain. This afforded the main circulation weather types (CWTs) for the winter and spring periods (since respiratory hospital admissions reached their maximum during these seasons) and the frequency distributions of these types were analyzed. A summary of the main characteristics of the hospital admission series and their distribution over the seven years studied, together with the frequency distributions of the admissions classified by sex and ages, for season, month and for each day of the week, is reported. In addition, a comparison between air-mass classification and hospital admissions is made using an admission index (AI). The results reveal different responses of respiratory admission rates to the eight air-mass types identified in winter and in spring. In winter, three air massess southwesterly (SW), anti-cyclonic (A) and hybrid anti-cyclonic southwesterly (HASW), are associated with values 1.5 times higher than the respective average admission rates, while in spring no significant differences are seen.     

Feasibility of Monitoring the Hontomín (Burgos, Spain) CO2 Storage Site Using a Deep EM Source

Geophysical methods have been used experimentally during the last decade, a period of strong development, being adopted as complementary techniques for characterizing and monitoring hydrocarbon and gas reservoirs. In this study, we evaluated the ability of the controlled source electromagnetic (CSEM) method to monitor the storage of CO₂ at the Research Laboratory on Geological Storage of CO₂ at Hontomín (Burgos, Spain). Two aspects of the CSEM monitoring were examined considering the geoelectrical structure at the site, the technological constraints and the noise conditions of the Hontomín area. Borehole-to-surface simulations were performed to evaluate the detectability of the resistivity changes in the reservoir and the capacity to determine the location of the CO₂ plume. The synthetic time-lapse study explores the possibilities of CSEM monitoring with a deep electric source. Three depths of the source are analyzed: above the plume, inside the plume, and beneath the stored CO₂. In terms of the Hontomín storage site, the study confirmed that a deep electric source located beneath the injection depth can provide valuable information on the behavior of the stored CO_2.     

Paired nakhlites MIL 090030, 090032, 090136, and 03346: Insights into the Miller Range parent meteorite

Abstract– Miller Range (MIL) 03346 is the most oxidized and least equilibrated nakhlite known and displays the highest amount of intercumulus phase. The discovery of three new nakhlites, MIL 090030, MIL 090032, and MIL 090136, in the Miller Range, Antarctica, geographically close to the location of MIL 03346, suggests that they may come from the same parent meteorite. In this study, we investigate the mineralogy and texture of cumulus and intercumulus phases, in situ major and trace element compositions for the cumulus phases, as well as pyroxene crystal size distribution patterns and spatial distribution patterns of MIL 090030, 090032, and 090136. Using these combined results, we conclude that the three nakhlites studied here are paired with MIL 03346. However, modal mineral abundances of MIL 090030, 090032, 090136, and 03346 exhibit variations indicating that a single sample of a Miller Range nakhlite is not modally representative of the parent meteorite and that analyses of multiple samples for a single nakhlite may be necessary to obtain representative modal data for placement in the cumulate pile. Our calculated parental melt composition based on all the paired samples confirms a previous study suggesting that the nakhlite parent melt crystallized as a closed system.     

Marbles from Roman Hispania: stable isotope and cathodoluminescence characterization

Pure white marble has been considered a valuable ornamental and architectural material since ancient times. Many scientific techniques have been used to create an extensive data base of “finger-prints” characterizing white marbles from the major classical quarries. However, determining the provenance of white marbles is a difficult task due to their similarity in physical and chemical parameters. Three techniques (petrography, cathodoluminescence and stable C and O isotopes) have been used to characterize white marbles from the ancient quarries of the Iberian Peninsula. Maximum grain size, texture and isotopic composition can be used to identify the different quarries. Each area is generally represented by several cathodomicrofacies, but quantitative CL analysis is also helpful in distinguishing those quarries for which the data provided by other techniques are not sufficiently diagnostic. The database and the discriminating criteria presented in this study have been tentatively applied to some ancient sculptures from the National Museum of Roman Art in Merida (Spain).     

Responses to salt stress in the halophyte Plantago crassifolia (Plantaginaceae)

General responses to salt stress have been investigated in the halophyte Plantago crassifolia. Seed germination was strongly inhibited by NaCl, although seed viability and germination capacity were not affected by salt pre-treatments. A concentration-dependent inhibition of plant growth was observed in the presence of NaCl, which was accompanied by the accumulation of Na⁺ ions in the leaves, as determined by cation exchange HPLC. A 20-fold increase of proline content in leaves was observed when plants were treated with 500 m NaCl, suggesting a protective role against high salinity stress for this amino acid, whose possible mechanism of action is discussed.     

Variscan tectonics in the Iberian Pyrite Belt, South Portuguese Zone

This paper aims to discuss the structural evolution of the Iberian Pyrite Belt during the Variscan Orogeny. It provides new structural data, maps and cross sections from the eastern part of the Iberian Pyrite Belt. Regional geology of the South Portuguese Zone and lithostratigraphy of the Iberian Pyrite Belt are first briefly summarised. Three roughly homoaxial deformation phases are distinguished, and are mainly characterised by south-verging multi-order folds, axial planar cleavages and thrusts. Three structural units are distinguished: the La Puebla de Guzmán and Valverde del Camino antiforms are rooted units related to the propagation of southward-directed thrust systems that may branch onto the lower décollement level of the South Portuguese Zone; El Cerro de Andévalo is a structurally higher unit, mainly composed of allochthonous D1 thrust nappes. No evidence of sinistral transpression has been found in the transected cleavage and the strike of S3 with respect to S2. Better evidence of transpression is the moderately to steeply westerly plunging folds that show S-type asymmetry in down-plunge view. Variscan deformation in the Iberian Pyrite Belt is defined as the combination of a dominant southwards shear and a sinistral E-shear caused by oblique continental collision between the South Portuguese plate and the Iberian Massif.