Nueva técnica de pegado con resina acrílica para preparar láminas delgadas para microscopía óptica

[ES] Tras un breve análisis de 10s pegamentos mis utilizados en la preparación de Iáminas delgadas de materiales geológicos con sus ventajas e inconvenientes, se describe un método de encolado rápido y fiable con resina acrilica. Se presenta además un diseño sencillo de una prensa con base de vidrio que permite el paso de la luz ultravioleta indispensable para el endurecimiento de la resina. La preparaciói? de láminas delgadas con diferentes tipos de rocas coherentes y sedimentos y suelos impregnados, asi como las pruebas sobre la calidad de las uniones, su resistencia al mecanizado, el indice de refracción de la resina y el envejecimiento, han dado resultados altamente satisfactorios.[EN] After a short comparative analysis of the most usual bonding techniques for rock thin section preparation, a new fast and reliable bonding technique with acrylic resin is described. A new design for a U.V. translucent press necessary for both a minimun glue thickness and as a requirement for the acrylic bonding to be completed, is also presented. Tests about thin section quality, mechanical resistance of the bond, refractive index and ageing performed on different hard rocks and impregnated sediments and soils, have given excellent results.Peer reviewe

Сравнительный анализ дедуктивных средств различных логических теорий (на примере времéнных и алетических логик)

The buoyancy of the lithospheric mantle relative to the asthenospheric mantle is the driving force of plate subduction and mantle delamination (the peeling off of the lithospheric mantle from the crust and its detachment and sinking into the asthenospheric mantle). Both mechanisms are often invoked for the evolution of collision zones, yet there are still open questions about the conditions under which they take place. The higher density of the lithosphere relative to the asthenosphere is thought to lead to subduction or delamination as it sinks. However, it is true only when the densities are temperature dependent. We adopt a mineral physics viewpoint where the density depends on temperature, pressure, and composition such that lithospheric mantle can be less dense than that of the underlying asthenosphere, posing a severe problem for the initiation of delamination. The density and its pressure-temperature dependence, in the lithosphere and asthenosphere are calculated from stable mineral assemblages computed using major oxides composition based on mantle xenoliths/garnet peridotites in the (CFMAS) framework. We present a parametric study on the relationship between slab buoyancy and convergence rate using a simple 2D kinematic numerical model, incorporating thermal advection and diffusion. We consider different types of the lithospheric mantle (e.g. Archon, Tecton, Proton, and Oceanic), subducting with different convergence rate and constant angle, into the asthenosphere. Our results suggest that Oceanic, Tecton and Proton lithospheres are always negatively buoyant and maximum negative buoyancy increases with the convergence velocity whereas Archons are always positively buoyant. In case of oceanic lithosphere maximum negative buoyancy also increases with its age for a given velocity. This is a SUBITOP (674899-SUBITOP-H2020-MSCA-ITN-2015) and MITE (CGL2014-59516) contribution.Peer Reviewe

3-D lithospheric structure and regional/residual Bouguer anomalies in the Arabia-Eurasia collision (Iran)

The aim of this work is to propose a first-order estimate of the crustal and lithospheric mantle geometry of the Arabia-Eurasia collision zone and to separate the measured Bouguer anomaly into its regional and local components. The crustal and lithospheric mantle structure is calculated from the geoid height and elevation data combined with thermal analysis. Our results show that Moho depth varies from ~42 km at the Mesopotamian-Persian Gulf foreland basin to ~60 km below the High Zagros. The lithosphere is thicker beneath the foreland basin (~200 km) and thinner underneath the High Zagros and Central Iran (~140 km). Most of this lithospheric mantle thinning is accommodated under the Zagros mountain belt coinciding with the suture between two different mantle domains on the Sanandaj-Sirjan Zone. The regional gravity field is obtained by calculating the gravimetric response of the 3-D crustal and lithospheric mantle structure obtained by combining elevation and geoid data. The calculated regional Bouguer anomaly differs noticeably from those obtained by filtering or just isostatic methods. The residual gravity anomaly, obtained by subtraction of the regional components to the measured field, is analyzed in terms of the dominating upper crustal structures. Deep basins and areas with salt deposits are characterized by negative values (~-20 mGal), whereas the positive values are related to igneous and ophiolite complexes and shallow basement depths (~20 mGal). © 2012 The Authors Geophysical Journal International © 2012 RAS.This research has been partly funded by ProjectsATIZA (CGL2009-09662-BTE) and TECLA (CGL2011–26670) and consolider-Ingenio 2010 Topo-Iberia (CSD2006-00041).Peer Reviewe

Numerical modelling of opposing subduction in the Western Mediterranean

© 2022 Elsevier. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/The geodynamic evolution of the Western Mediterranean related to the closure of the Ligurian-Tethys ocean is not yet fully resolved. We present a new 3D numerical model of double subduction with opposite polarities fostered by the inherited segmentation of the Ligurian-Tethys margins and rifting system between Iberia and NW Africa. The model is constrained by plate kinematic reconstructions and assumes that both Alboran-Tethys and Algerian-Tethys plate segments are separated by a NW-SE transform zone enabling that subduction polarity changes from SE-dipping in the Alboran-Tethys segment to NW-dipping in the Algerian-Tethys segment. The model starts about late Eocene times at 36.5 Ma and the temporal evolution of the simulation is tied to the geological evolution by comparing the rates of convergence and trench retreat, and the onset and end of opening in the Alboran Basin. Curvature of the Alboran-Tethys slab is imposed by the pinning of its western edge when reaching the end of the transform zone in the adjacent west-Africa continental block. The progressive curvature of the trench explains the observed regional stress reorientation changing from N-S to NW-SE and to E-W in the central and western regions of the Alboran Basin. The increase of the retreat rates from the Alboran-Tethys to the Algerian-Tethys slabs is compatible with the west-to-east transition from continental-to-magmatic-to-oceanic crustal nature and with the massive and partially synchronous calc-alkaline and alkaline magmatism.We are indebted to Prof. Zheng-Xiang Li as Editor of Tectonophysics, and Prof. Sierd Cloetingh and an anonymous reviewer for their valuable suggestions and constructive comments which improved the previous version of the paper. We acknowledge discussions with Chiara Mac- chiavelli and Marc Viaplana during the development of this work. This work is funded by the SUBTETIS (PIE-CSIC-201830E039, CSIC), ALORBE (PIE-CSIC-202030E310), GeoCAM (PGC2018-095154-B-I00, Spanish Government), Equinor R&T Fornebu (Norway), and the Gen- eralitat de Catalunya grant (AGAUR 2017 SGR 847). We also thank the computer resources at MareNostrum and the technical support provided by the Barcelona Supercomputing Center (BSC) through several projects (AECT-2019-1-0013 and AECT-2019-2-0005). S. Z. has been funded by the MCIN/AEI doi:10.13039/501100011033 through project PID2020- 113463RB-C32, and by EU H2020 MSCA grant agreement No 777778. This work has been done in the framework of the Unidad Asociada of LACAN-UPC with CSIC and using the facilities of the Laboratory of Geodynamic Modelling from Geo3BCN-CSIC.Peer ReviewedPostprint (published version

Crustal-scale cross-sections across the NW Zagros belt: Implications for the Arabian margin reconstruction

Quantified balanced and restored crustal cross-sections across the NW Zagros Mountains are presented in this work integrating geological and geophysical local and global datasets. The balanced crustal cross-section reproduces the surficial folding and thrusting of the thick cover succession, including the near top of the Sarvak Formation (∼90 Ma) that forms the top of the restored crustal cross-section. The base of the Arabian crust in the balanced cross-section is constrained by recently published seismic receiver function results showing a deepening of the Moho from 42 ± 2 km in the undeformed foreland basin to 56 ± 2 km beneath the High Zagros. The internal parts of the deformed crustal cross-section are constrained by new seismic tomographic sections imaging a ∼50° NE-dipping sharp contact between the Arabian and Iranian crusts. These surfaces bound an area of 10800 km2 that should be kept constant during the Zagros orogeny. The Arabian crustal cross-section is restored using six different tectonosedimentary domains according to their sedimentary facies and palaeobathymetries, and assuming Airy isostasy and area conservation. While the two southwestern domains were directly determined from well-constrained surface data, the reconstruction of the distal domains to the NE was made using the recent margin model of Wrobel-Daveau et al. (2010) and fitting the total area calculated in the balanced cross-section. The Arabian continental-oceanic boundary, at the time corresponding to the near top of the Sarvak Formation, is located 169 km to the NE of the trace of the Main Recent Fault. Shortening is estimated at ∼180 km for the cover rocks and ∼149 km for the Arabian basement, including all compressional events from Late Cretaceous to Recent time, with an average shortening rate of ∼2 mm yr-1 for the last 90 Ma. © 2011 Cambridge University Press.We thank the following projects for their additional support: DARIUS Programme and its sponsors, TopoMed CGL2008– 03474-E/BTE, ESF-Eurocores 07-TOPOEUROPE-FP006, TopoAtlas (CGL2006–05493/BTE), ATIZA (CGL2009– 09662-BTE) and Consolider-Ingenio 2010 Topo-Iberia (CSD2006–00041).Peer Reviewe

Licitació per a la rehabilitació com a Centre d'Entitats de la masia de Can Rigalt a Sant Adrià

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Concurs per l'adequació de l'espai expositiu: "Sala Visions" a l'Ajuntament de Barcelona

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Selecció d'una societat tècnica de serveis per a la proposta d'imatge, projecte i implantació

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Licitació per a a una graderia i vestidors a Sant Adrià del Besós

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Considering adaptive genetic variation in climate change vulnerability assessment reduces species range loss projections

Local adaptations can determine the potential of populations to respond to environmental changes, yet adaptive genetic variation is commonly ignored in models forecasting species vulnerability and biogeographical shifts under future climate change. Here we integrate genomic and ecological modeling approaches to identify genetic adaptations associated with climate in two cryptic forest bats. We then incorporate this information directly into forecasts of range changes under future climate change and assessment of population persistence through the spread of climate-adaptive genetic variation (evolutionary rescue potential). Considering climate-adaptive potential reduced range loss projections, suggesting that failure to account for intraspecific variability can result in overestimation of future losses. On the other hand, range overlap between species was projected to increase, indicating that interspecific competition is likely to play an important role in limiting species’ future ranges. We show that although evolutionary rescue is possible, it depends on a population’s adaptive capacity and connectivity. Hence, we stress the importance of incorporating genomic data and landscape connectivity in climate change vulnerability assessments and conservation management