The Monasterio thrust (Ossa-Morena Area) Microstructures and geodynamic implications

[Resumen] El cabalgamiento de Monesterio (EGUILUZ, 1988) se situa en el sector central de la antiforma de igual nombre y ha sido reconocido en un trayecto de más de 30 Km desde el SE de Fregenal de la Sierra hasta la Venta del Culebrín, al Se de Monesterio. Se trata de un accidente dúctil o frágil-dúctil que superpone un conjunto de cuarzoesquistos biotíticos de gradio medio a alto, metapelitas y granitoides anatécticos (Sucesión de Montemolín) sobre una serie de metagrauvacas y pizarras volcanoclásticas con cuarcitas negras (Sucesión Tentudia), de grado bajo a muy bajo. Este accidente se produce durante la primera fase de deformación hercínica y corta dos quistosidades previas desarrolladas en los materiales proterozoicos. Puede considerarse como una posible zona de raíz de los pliegues tumbados que afectan a las series del Paleozoico inferior ampliamente representadas en el flanco meridional de la antiforma de Monesteiro (sector Oliva de la Frontera-Higuera la Real). El cabalgamiento lleva asociadas estructuras penetrativas en una amplia zona que, en cartografía, tiene una anchura superior a los 6 Km en el bloque superior y a los 2 Km en el inferior. Este accidente corta a distintos materiales, lo que da lugar al desarrollo de rocas miloníticas de tipos variados[Abstract] The Monesterio Thrust (EGUILUZ, 1988) is situated at the central area of the Monesterio antiform (SW Iberian Massif). It has been identified for more than 30 Km, from SE Fregenal de la Sierra to Venta del Culebrín (to the SE 01 Monesterio). This is a ductile to brittle-ductile thrust where medium -to high- grade quarzschists, anatectic metapelites and granitoids (Montemolín Succession) override a low -to very low- grade group made of meta-graywackes and 'volcanoclastic slates with interbedded black quartzites (Tentudía Succession). Thrusting takes place during the hercynian first deformation phase and crosscuts two previous schistosities developed within proterozoic materials. The Monesterio Thrust can ben regarded as the root of large, Upper Paleozoic recumbent folds affecting Lower Paleozoic series outcropping in the southern limb of the Monesterio antiform (Oliva de la Frontera-Higuera de Llerena area). The thrust associates penetrative structures over an areally wide hand which attains up to 6 Km width in the upper, allochthon block, and up to 2 Km in the autochthon. Many kinds of materials are cross-cut, giving rise to the generation on a varied set of mylonitic rocks

Análisis de lineamientos detectados por sensores remotos sobre imágenes landsat: la influencia del factor humano y su relevancia en estudios tectónicos o de investigación minera

[Abstract] In the present work we deal with the influence of the so-called «human component » on lineament photointerpretation and LANDSAT images. The statistical study of the lineaments drawn by three different analysts on the same LANDSTAT image is performed, being the tested a geologically well-known portion of the Iberian Hercynian Mássif: the Badajoz-C6rdoba Shear Zone. The results obtained let us consider attentively the role played by the analyst subjectivity on the finallineament networks. As a result, the consequence of the studies of this type on mineral exploration and tectonics are discussed, being undeniable the validity of this technique.[Resumen] En este trabajo se estudia la influe'ncia del que se ha dado en denominar «componente humano» en la fotointerpretación de lineamentos estructurales sobre imágenes LANDSAT. Se realiza un estudio estadístico de las fotolíneas dibujadas sobre un mismo soporte fotográfico por tres analistas diferentes. El área uálizada para la realización de la prueba es el Corredor Blastomilonítico de Badajoz Córdoba, una región relativamente bien conocida del Macizo Ibérico. Los resultados y conclusiones alcanzados permiten efectuar una estimación semicuantitativa del papel jugado por la subjetividad del analista sobre las redes de fotolíneas obtenidas. Las principales consecuencias que se derivan de este estudio son discutidas desde la perspectiva de la tectónica y de la exploración mineral, resaltando la validez de la técnica de teledetección utilizada

Influence of Tillage and Liming on N2O emission from a rainfed crop

Nitrous oxide (N2O) is the main greenhouse gas (GHG) produced by agricultural soils due to microbial processes. The application of N fertilizers is associated with an increase of N2O losses. However, it is possible to mitigate these emissions by the introduction of adequate management practices (Snyder et al., 2009). Soil conservation practices (i.e.no tillage, NT) have recently become widespread because they promote several positive effects (increases in soil organic carbonand soil fertility, reduction of soil erosion, etc). In terms of GHG emissions, there is no consensus in the literature on the effects of tillage on N2O. Several studies found that NT can produce greater (Baggs et al., 2003), lower (Malhi et al., 2006) or similar (Grandey et al., 2006) N2O emissions compared to traditional tillage (TT). This large uncertainty is associated with the duration of tillage practices and climatic variability. Liming is widely use to solve problems of soil acidity (Al toxicity, yield penalties, etc). Several studies show a decrease in N2O emissions with liming (Barton et al., 2013) whereas no significant effects or increases were observed in others (Galbally et al., 2010). The aim of this work was to evaluate the effects of tillage (NT vs TT) and liming application or not of Ca-amendment) on N2O emissions from an acid soil during a rainfed crop

Garnet-clinopyroxene bearing assemblages in the 'upper catazonal unit' of the Cabo Ortega! Complex (NW Spain)

[Resumen] Se han estudiado los siguientes materiales de la 'unidad catazonal superior' del Complejo del Cabo Ortegal conteniendo asociaciones con granate-clinopiroxeno: eclogitas, granulitas básicas, intercalaciones gneísicas en las granulitas, piroxenitas con granate, gneises de la aureola de contacto de las rocas ultramáficas, metabasitas de la 'formación Candelaria' y 'carbonatitas'. Los datos termobarométricos obtenidos sugieren que, mientras que los minerales de algunos de estos materiales han sufrido importantes reajustes composicionales durante los procesos de retromorfosis (e. g. granulitas con distena, intercalaciones gneísicas en granulitas, -intercalaciones u1tramáficas en gneises, etc.), otros han conservado elementos mineralógicos con la composición alcanzada durante el episodio metamórfico que originó la formación de las asociaciones con granate-clinopiroxeno. Este segundo grupo de materiales puede subdividirse en dos categorías: 1) aquellos materiales en los que la asociación granate-clinopiroxeno se formó en torno a los 800 oC y 15 ± 1. 5 kbar (eclogitas 'tipo-I', granulitas de la 'formación Bracariza', piroxenitas con granate de los macizos de rocas u1tramáficas 'carbonatitas'), y, 11) aquellos en los que dicha asociaci6n se formó a unos 700 oC y la misma P aproximadamente (eclogitas y granulitas intercaladas en las formaciones gneísicas). Aunque las diferencias no son muy importantes, es posible que los dos conjuntos litológicos representen dos gradientes metamórficos distintos y, por tanto, la existencia en dicha 'unidad' de materiales con diferentes historias tectono-metamórficas.[Abstract] The following materials from the 'uper' catazonal unit' of the Cabo Ortegal Complex, containing garnet-clinopyroxene assemblages, have been studied: eclogites, basic granulites, gneissic intercalations within granulites, garnetbearing pyroxenites, gneisses from the contact aureole of the ultramafic rocks, metabasites from the 'Candelaria formation' and 'carbonatites'. The thermobarometric data obtained from this study suggest that the minerals from several of those materials underwent strong compositional readjustements during the subsequent retromorphic events (e. g. the kyanite-bearing granulites, the gneissic intercalations in granulites, the u1tramafic intercalations in gneisses, etc.). The remaining materials have preserved mineral compositions attained during the metamorphic episode that produced the garnetclinopyroxene assemblages; these materials may be classified as follows: 1) those in which the garnet-clinopyroxene assemblage formed at ca. 800 oC and 15 ± ± 1,5 kbar ('type-I' eclogites, granulites from the 'Bacariza formation', garnetbearing pyroxenites from the ultramafic massifs and 'carbonatites'), and, 11) those where the same association developed at ca 700 oC and more or less the same P conditions (eclogites and granulites intercaled in gneisses). Although these differences in P and Tare not very important, it is possible that these two groups represent two different metamorphic gradients, and therefore the existence in this 'unit' of the Complex of two lithological sub-units with different tectono-metamorphic histories

The clinical and molecular cardiometabolic fingerprint of an exploratory psoriatic arthritis cohort is associated with the disease activity and differentially modulated by methotrexate and apremilast

Objectives: (1) To evaluate clinical and molecular cardiovascular disease (CVD) signs and their relationship with psoriatic arthritis (PsA) features and (2) to identify a clinical patient profile susceptible to benefit from methotrexate (MTX) and/or apremilast regarding CVD risk. Methods: This cross-sectional study included 100 patients with PsA and 100 age-matched healthy donors. In addition, an exploratory cohort of 45 biologically naïve patients treated for 6 months with apremilast, MTX or combined therapy according to routine clinical practice was recruited. Extensive clinical and metabolic profiles were obtained. Ninety-nine surrogate CVD-related molecules were analysed in plasma and peripheral blood mononuclear cells (PBMCs). Hard cluster analysis was performed to identify the clinical and molecular phenotypes. Mechanistic studies were performed on adipocytes. Results: Cardiometabolic comorbidities were associated with disease activity and long-term inflammatory status. Thirty-five CVD-related proteins were altered in the plasma and PBMCs of PsA patients and were associated with the key clinical features of the disease. Plasma levels of some of the CVD-related molecules might distinguish insulin-resistant patients (MMP-3, CD163, FABP-4), high disease activity (GAL-3 and FABP-4) and poor therapy outcomes (CD-163, LTBR and CNTN-1). Hard cluster analysis identified two phenotypes of patients according to the rates of cardiometabolic comorbidities with distinctive clinical and molecular responses to each treatment. Conclusions: (1) Novel CVD-related proteins associated with clinical features could be emerging therapeutic targets in the context of PsA and (2) the pleiotropic action of apremilast could make it an excellent choice for the management of PsA patients with high CVD risk, targeting metabolic alterations and CVD-related molecules

Changing environments during the Middle-Upper Palaeolithic transition in the eastern Cantabrian Region (Spain): direct evidence from stable isotope studies on ungulate bones

Environmental change has been proposed as a factor that contributed to the extinction of the Neanderthals in Europe during MIS3. Currently, the different local environmental conditions experienced at the time when Anatomically Modern Humans (AMH) met Neanderthals are not well known. In the Western Pyrenees, particularly, in the eastern end of the Cantabrian coast of the Iberian Peninsula, extensive evidence of Neanderthal and subsequent AMH activity exists, making it an ideal area in which to explore the palaeoenvironments experienced and resources exploited by both human species during the Middle to Upper Palaeolithic transition. Red deer and horse were analysed using bone collagen stable isotope analysis to reconstruct environmental conditions across the transition. A shift in the ecological niche of horses after the Mousterian demonstrates a change in environment, towards more open vegetation, linked to wider climatic change. In the Mousterian, Aurignacian and Gravettian, high inter-individual nitrogen ranges were observed in both herbivores. This could indicate that these individuals were procured from areas isotopically different in nitrogen. Differences in sulphur values between sites suggest some variability in the hunting locations exploited, reflecting the human use of different parts of the landscape. An alternative and complementary explanation proposed is that there were climatic fluctuations within the time of formation of these archaeological levels, as observed in pollen, marine and ice cores.This research was funded by the European Commission through a Marie Curie Career Integration Grant (FP7- PEOPLE-2012-CIG-322112), by the Spanish Ministry of Economy and Competitiveness (HAR2012-33956 and Ramon y Cajal-2011-00695), the University of Cantabria and Campus International to ABMA. Radiocarbon dating at ORAU was funded by MINECO-HAR2012-33956 project. J.J was supported initially by the FP7- PEOPLE-2012-CIG-322112 and later by a Marie Curie Individual Fellowship (H2020-MSCA-IF-2014-656122). Laboratory work, associated research expenses and isotopic analysis were kindly funded by the Max Planck Society to M.R

Geobiology of a lower Cambrian carbonate platform, Pedroche Formation, Ossa Morena Zone, Spain

The Cambrian Pedroche Formation comprises a mixed siliciclastic-carbonate succession recording subtidal deposition on a marine platform. Carbonate carbon isotope chemostratigraphy confirms previous biostratigraphic assignment of the Pedroche Formation to the Atdabanian regional stage of Siberia, correlative to Cambrian Series 2. At the outcrop scale, thrombolitic facies comprise ~. 60% of carbonate-normalized stratigraphy and coated-grains another ~. 10%. Petrographic point counts reveal that skeletons contribute at most 20% to thrombolitic inter-reef and reef-flank lithologies; on average, archaeocyath clasts make up 68% of skeletal materials. In contrast, petrographic point counts show that skeletons comprise a negligible volume of biohermal and biostromal thrombolite, associated nodular carbonate facies, and ooid, oncoid and peloid grainstone facies. As such, archaeocyathan reefal bioconstructions represent a specific and limited locus of skeletal carbonate production and deposition. Consistent with data from coeval, globally dispersed lower Cambrian successions, our analysis of the Pedroche Formation supports the view that lower Cambrian carbonates have more in common with earlier, Neoproterozoic deposits than with younger carbonates dominated by skeletal production and accumulation. © 2013 Elsevier B.V.Jessica R. Creveling, David Fernández-Remolar, Marta Rodríguez-Martínez, Silvia Menéndez, Kristin D. Bergmann, Benjamin C. Gill, John Abelson, Ricardo Amils, Bethany L. Ehlmann, Diego C. García-Bellido, John P. Grotzinger, Christian Hallmann, Kathryn M. Stack, Andrew H. Knol

Response of Arctic ozone to sudden stratospheric warmings

Sudden stratospheric warmings (SSWs) are the main source of intra-seasonal and interannual variability in the extratropical stratosphere. The profound alterations to the stratospheric circulation that accompany such events produce rapid changes in the atmospheric composition. The goal of this study is to deepen our understanding of the dynamics that control changes of Arctic ozone during the life cycle of SSWs, providing a quantitative analysis of advective transport and mixing. We use output from four ensemble members (60 years each) of the Whole Atmospheric Community Climate Model version 4 performed for the Chemistry Climate Model Initiative and also use reanalysis and satellite data for validation purposes. The composite evolution of ozone displays positive mixing ratio anomalies of up to 0.5-0.6 ppmv above 550 K (similar to 50 hPa) around the central warming date and negative anomalies below (-0.2 to -0.3 ppmv), consistently in observations, reanalysis, and the model. Our analysis shows a clear temporal offset between ozone eddy transport and diffusive ozone fluxes. The initial changes in ozone are mainly driven by isentropic eddy fluxes linked to enhanced wave drag responsible for the SSW. The recovery of climatological values in the aftermath of SSWs is slower in the lower than in the upper stratosphere and is driven by the competing effects of cross-isentropic motions (which work towards the recovery) and isentropic irreversible mixing (which delays the recovery). These features are enhanced in strength and duration during sufficiently deep SSWs, particularly those followed by polar-night jet oscillation (PJO) events. It is found that SSW-induced ozone concentration anomalies below 600 K (similar to 40 hPa), as well as total column estimates, persist around 1 month longer in PJO than in non-PJO warmings