2,122 research outputs found

    Características del emplazamiento, Petrología y Geoquímica de Espessartitas en el Plutón de la Maladeta: estudio preliminar

    Get PDF
    [Resumen] Los diques de lamprófidos espessartíticos son frecuentes en el plutón circunscrito de La Maladeta (Pirineos Centrales, Huesca-Lérida). Su emplazamiento, se produjo bajo unas condiciones confinadas y con un control estructural, afectando a todos los litotipos plutónicos (Cuarzo-Gabros, Granodioritas, Tonalitas y Sienogranitos) y, también a las etapas filonianas ácidas (Aplita y Pegmatitas). La composición mineral (con destacado contenido en anfíboles de composición hornblenda pargasítica) y la Geoquímica, definen una afinidad calco-alcalina cuya signatura en elementos mayores y trazas, es bastante análoga a la óbtenida en lamprófidos similares, emplazados en macizos granodioríticos. Esta afinidad presenta una relación genética con la granodiorita, como término volumétricamente más representativo del Macizo.[Abstract] Lamprophyric dykes (Spessartites) are frequent in the Maladeta circumscribe plutonic massif (Central Pyrenees, Huesca-Lérida). The setting of these dykes, under confinant strains and with a structural control, affected to á1l the plutonic rocktypes (Quanz-Gabbros, Granodiorites, Tonalites and Syenogranites) and to the acid dykes (Aplites and Pegmatites) too. The mineral (with high contents in Pargasitic-Hornblende amphiboles) and geochemical compositions, define a calc-alkaline affinity, very similar (Major and trace elements) to that of analogue lan prophyres, set in Granodioritic massifs. This affinity shows a genetic relation with the Granodiorite, as volumetrically most representative rock-type in the massif

    Composition and barometric implications of the amphiboles from the Maladeta plutonic complex (Central Pyrenees, Huesca-Lérida)

    Get PDF
    [Abstract] The composition of the amphiboles in basic rocks (gabbros and diorites), granodiorites, monzogranites with minor amphibole and mafic microgranular enclaves from the Maladetta massif, corresponds to calcic terms (magnesioHornblende, actinolitic hornblende and actinolite), with reduced values ofAl tot• The main substitutional types are edenite, pargasite and Ti-Tschermakite, with other minor types, generating compositions with an AIIV excess. The application of three of the proposed calibrations for the Altot in Horblende geobarometer, gives anomalously low pressure values for the cristallyzation of the plutonic rock-types, suggesting that the amphibole crystals were formed below 2 Kbar of pressure, and in a continous way to subsolidus conditions,probably at the same time as AI-saturating phases formed

    Extended X-ray emission around RRAT J1819-1458

    Full text link
    We present new imaging and spectral analysis of the recently discovered extended X-ray emission around the high-magnetic-field rotating radio transient RRAT J1819-1458. We used two Chandra observations, taken on 2008 May 31 and 2011 May 28. The diffuse X-ray emission was detected with a significance of ~19sigma in the image obtained by combining the two observations. Long-term spectral variability has not been observed. Possible scenarios for the origin of this diffuse X-ray emission, further detailed in Camero-Arranz et al. (2012), are here discussed.Comment: Proceedings of IAUS 291 "Neutron Stars and Pulsars: Challenges and Opportunities after 80 years", J. van Leeuwen (ed.); 4 pages, 3 figure

    Beyond the First Recurrence in Scar Phenomena

    Full text link
    The scarring effect of short unstable periodic orbits up to times of the order of the first recurrence is well understood. Much less is known, however, about what happens past this short-time limit. By considering the evolution of a dynamically averaged wave packet, we show that the dynamics for longer times is controlled by only a few related short periodic orbits and their interplay.Comment: 4 pages, 4 Postscript figures, submitted to Phys. Rev. Let

    Las doleritas toleiticas triasicas del sector SE de la Cordillera Ibérica : Petrología y Geoquímica

    Get PDF
    Las doleritas toleíticas aflorantes en diapiros triásicos del SE de la Cordillera Ibérica (Alfarp, Quesa y Lugar Nuevo de Fenollet, SE de Valencia) representan líquidos diferenciados (valores bajos en Ni, Cr y mg*) emplazados como sills, de escaso espesor, por debajo de sedimentos (arcillas, margas y yesos), poco consolidados, del límite Triásico superior-Hettangiense. Su composición mineral y geoquímica, con afinidad toleítica continental y similitud a MORB, evidencia el carácter menos diferenciado de las doleritas de Alfarp, respecto a las de Quesa, siendo las doleritas aflorantes en Fenollet las que presentan una composición más evolucionada. Estas doleritas son la expresión de un magmatismo poco profundo, asociado al inicio del rifting mesozoico, desarrollado en la zona de intersección del rift celtibérico y el borde NE del surco bético. Este magmatismo presenta claras diferencias respecto a las doleritas toleíticas, menos diferenciadas, de los dominios pirenaico y bético.The tholeiitic dolerites that crop out in three diapirs of the SE of the Iberian Chain (Alfarp, Quesa and Lugar Nuevo de Fenollet, Valencia), are the expression of evolved (iow Ni, Cr and mg* values) basic magmas, injected into poorly lithified sediments (iutites, marls and gypsum) which represent the Upper Triassic (Keuper facies)-Hettangian boundary, developing sills with reduced thickness. Their mineral and whole-rock geochemical compositions indicate a continental tholeiitic affinity and certain similarities to a MORB composition and, on the other hand, show that the Alfarp dolerites represent the less evolved compositions, whereas the Fenollet dolerites show a significantly greater differentiation. These rocks are the expression of a shallow magmatism, related to the initial stages of the mesozoic rifting that affected the intersection of the Celtiberian Rift with the Betic Graben. This magmatism is clearly different of the isochronous tholeiitic magmatism (dolerites) which crops out at the Pyrenees and [email protected]

    The development of a resource-efficient photovoltaic system

    No full text
    This paper presents the measures taken in the demonstration of the photovoltaic case study developed within the European project ‘Towards zero waste in industrial networks’ (Zerowin), integrating the D4R (Design for recycling, repair, refurbishment and reuse) criteria at both system and industrial network level. The demonstration is divided into three phases. The first phase concerns the development of a D4R photovoltaic concept, the second phase focused on the development of a specific component of photovoltaic systems and the third phase was the demonstration of the D4R design in two complete photovoltaic systems (grid-connected and stand-alone). This paper includes a description of the installed photovoltaic systems, including a brief summary at component level of the lithium ion battery system and the D4R power conditioning system developed for the pilot installations. Additionally, industrial symbioses within the network associated with the photovoltaic systems and the production model for the network are described

    Setting conclitions, Petrology ancl Geochemistry of calc-alkaline rhyolites, stephanian-permian, in the iberian chains

    Get PDF
    [Resumen] Se exponen los caracteres del emplazamiento, la composición petrológica y geoquímica de unos sills riolíticos que, con afinidad calco-alcalina, se emplazaron, bajo un ambiente sin-colisional, en diversos sectores de la Cadena Ibérica. Estas riolitas representan un origen crustal, con baja tasa de fusión, previo a un magmatismo calco-alcalino de origen subcrustal.[Abstract] The setting characters, the petrological and geochemical composition are exposed for sorne rhyolitic sills, with calc-alkaline affinity, which were set, in a syncollisional environment, in several areas of the Iberian Chains. These rhyolites represent a crustal origin, with a low degree of fussion, previous to a calc-alkaline magmatism of subcrustal origino
    corecore