An optimized thermal extraction system for preparation of water from fluid inclusions in speleothems

The fluid inclusions present in speleothems (secondary mineral deposits formed in caves) are a relict sample of the parent seepage water from which the speleothem was deposited and determination of their composition can solve the palaeotemperature equation for the precipitation of speleothem carbonate. We have extracted fluid inclusions using a newly-designed thermal vacuum extraction method in stalagmites and stalactites from Nerja Cave, Southern Spain. Optimal conditions were found to involve heating samples crushed to 0.8-2mm for 3 hours at 300-400ºC. Waters extracted from modern aragonitic speleothem samples produced results on the Meteoric Water Line defined by modern infiltration and other waters associated with the cave and hence demonstrate an absence of fractionation effects. This successfully demonstrates the utility of the method

Preliminary hydrogeological characterization of an evaporite karst area (province of Cordoba, South Spain)

The northern sector of the Subbetic Domain in the Betic Cordillera is formed by an olistostrome unit known as the Chaotic Subbetic Complex (CSC). This megabreccia is basically made of Triassic (Keuper) clays and evaporites (gypsum, anhidrite and halite) as well as blocks of other lithologies (limestones, dolostones, sandstones, etc). Despite that low permeability has been traditionally assumed for these materials, water flow and storage through them is likely derived of their aquitard behavior, but also because of the highly permeable conduits generated by dissolution/karstification processes within the evaporite rocks. The geological complexity of the CSC materials determines their hydrogeological heterogeneity, with groundwater flow systems of different length and various scales from recharge areas to discharge zones. Three springs draining the CSC outcrops have been identified around an evaporitic karst plateau located between the Anzur River (to the North) and the Genil River (to the South), in the province of Cordoba (Spain). Data logger devices have been installed in two of them, located at the Anzur River (left margin), providing an hourly record of discharge, electrical conductivity and water temperature. Water samples have been collected fortnightly for subsequent chemical analysis. After two years of record, the results obtained show that the response of the springs to rainfall events is completely different between them. One has a clearly karstic behavior, with a rapid response to recharge whereas the other one is more inertial, and variations in its waters occur in a yearly scale. This is an evidence of the aforementioned hydrogeological heterogeneity of the CSC.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

La hidrodiversidad como condicionante del patrimonio natural y cultural. El ejemplo de Los Hoyos (provincias de Málaga y Granada)

El paraje de Los Hoyos es un pequeño enclave kárstico-evaporítico situado entre las provincias de Málaga y Granada. Cuenta con humedales y manantiales, ambos relacionados con las aguas subterráneas, que presentan un amplio rango de mineralizaciones (dulce, salobre, hipersalina) y de facies hidroquímicas (bicarbonatada-cálcica, sulfatada-cálcica, clorura-sódica), fruto de la geología del medio y de distintos procesos hidrogeoquímicos (disolución y precipitación mineral, evapoconcentración). Más allá del valor ecológico de este entorno, en este trabajo se analizan otros valores ligados al agua: intrínsecos, culturales, estéticos, económicos, funcionales y científicos. Todo ello, en su conjunto, hace de este paraje un lugar digno de protección y ejemplifica la importancia de la hidrodiversidad sobre el patrimonio natural y cultural. Los datos aquí presentados y discutidos permiten realizar una propuesta de definición de la hidrodiversidad, que puede servir de base para avanzar en su descripción.UNESCO, Geoparque Montañas de Courel, UICN Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

U-series and radiocarbon cross dating of speleothems from Nerja Cave (Spain): Evidence of open system behavior. Implication for the Spanish rock art chronology

Two stalagmites from Nerja cave (Andalusia, Spain) were studied. The cave is well known because of its long human occupation from the Upper Palaeolithic to the Chalcolithic and its abundant parietal prehistoric Art. The aims of this study were twofold: i) to compare uranium/thorium (Th/U) and Carbon-14 (C) ages obtained all along the growth axis of the stalagmites in order to understand the consequences of diagenetic processes on the validity of radiometric ages; ii) as one of the stalagmites contains black layers, attributed to combustion soot, to establish when these intense hearths were used and by which culture. Th/U and C ages were coupled with mineralogical studies using FTIR (Fourier-transform infrared spectroscopy) and thin section observations. The first stalagmite (GN16-9b) displays Th/U ages in stratigraphic order, and compatible with C ages corrected for a few percent of dead carbon. Homogeneous composition of aragonitic crystals characterized by their needle-like texture is observed throughout this speleothem. For the second stalagmite (GN16-7), in contrast, Th/U ages display large significant inversions and discordant results on the upper part and at the base of the stalagmite, suggesting a possible open system behavior for this chronometer. Interestingly, C ages are in stratigraphic order all along the stalagmite and are compatible with Th/U ages only in its central part. Mineralogical studies display evidence of aragonite to calcite transformation at the top and a complex mineralogical assemblage with interlayered silicates (possibly clays) and calcitic mineralogy for the base of GN16-7. In these parts, discordant Th/U ages were measured. In the middle part of the stalagmite, however, where the fibrous aragonite is well preserved, the C and Th/U ages agree. Our data suggest that in the case of aragonite to calcite transformation as shown here, Th/U ages are biased, but C ages seem to remain accurate, as already observed in aragonitic marine bio minerals. C ages obtained are used for the chronology of the soot layer, determined here between 7900 and 5500 years Cal BP, coherent with previous analysis of charcoals in the same sector of the cave. This study highlights the importance of working with at least two chronometers when stratigraphic age verification is not possible, as is the case of some parietal CaCO thin layers used for rock art dating. Recent Th/U ages published for carbonate deposits on Spanish parietal Art are discussed in light of this demonstration.This research was funded by ANR (grant number ANR-18-CE27- 0004, ApART project) and supported by the Paris Ile-de-France Region – DIM “matérieux Anciens et Patrimoniaux” for FTIR analysis. The authors thank LMC14 staff (Laboratoire de Mesure du Carbone-14), ARTEMIS national facility, for the results obtained with the Accelerator Mass Spectroscopy method, and the PANOPLY analytical platform. This research is part of the “Proyecto General de Investigación aplicada a la conservación de Cueva de Nerja” authorised by the Junta de Andalucía and financed by the Fundación de Servicios Cueva de Nerja. The authors also wish to thank the “Instituto de Investigación Cueva de Nerja” for supporting this research. M.A.Medina-Alcaide has a Postdoctoral Fyssen Grant; the results presented in this paper are included in the PID2019-107262GB-I00 and PDC2021-121501-I00 grants funded by MCIN/AEI/10.13039/501100011033

Estudio preliminar de la hidrodiversidad de humedales andaluces de origen kárstico-evaporítico

Los resultados preliminares obtenidos muestran una gran variedad de facies hidroquímicas (Fig. 3 y 4) y un amplio rango de mineralización de las aguas (Fig. 3 y Tab. 1). Los valores isotópicos de δ18O y δD de las muestras (Fig. 5) indican un enriquecimiento isotópico y presentan un claro desvío con respecto a las líneas meteóricas local y global. Ello demuestra la influencia de la evaporación sobre el agua de los humedales estudiados, más patente en el caso de lagunas estacionales con periodo de inundación prolongado que en aquellas con un hidroperiodo más efímero. Las aguas de las lagunas permanentes, pese a estar expuestas de forma continua a la evaporación, se sitúan en la figura 5 en una posición intermedia, lo que podría deberse a la mezcla de aguas evaporadas con otras de aporte subterráneo. Los humedales de génesis kárstico-evaporítica, pese a tener un origen similar, presentan una gran diversidad geomorfológica, hidrológica e hidrogeológica como consecuencia de condiciones topográficas y geológicas particulares así como de su ubicación dentro de sistemas de flujo subterráneo locales, intermedios o regionales. Dichas particularidades han de ser tomadas en consideración a la hora de gestionar estas áreas naturales y plantear medidas de conservación y restauración, por lo que es necesario profundizar en el conocimiento hidrogeológico de los CCS y de la relación de las aguas subterráneas con los humedales formados en este contexto.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Grupo Español de la Asociación Internacional de Hidrogeólogo

Primer curso de Bioderecho y los Comités de Ética en Investigación “Cuestiones fundamentales desde el Derecho, la Ética y la Ciencia"

Contenido resumen del primer curso de Bioderecho y los Comités de Ética en Investigación “Cuestiones fundamentales desde el Derecho, la Ética y la Ciencia”. Organizado por el Comité de Ética en Investigación del Centro Universitario de la Costa. Celebradas el 23 y 24 de octubre de 2014 en Puerto Vallarta, México

Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

Geoquímica de carbonatos relacionados con etapas de emersión

Se realiza un estudio geoquímico sobre materiales carbonatados de diferentes edades procedentes esencialmente de la cordillera betica, y cuya génesis estuvo íntimamente relacionada con las etapas de emersión acaecidas durante distintos intervalos de tiempo y que afectaron a esta región durante la etapa de margen continental y durante la etapa postorogenica. Principalmente el estudio geoquímico esta basado en el análisis de las razones isotopicas 13c/12c y 18o/16o, y completado con los datos obtenidos a partir del microanálisis de elementos traza y de los análisis mineralógicos, así como los resultados obtenidos con el empleo de otras técnicas. El objetivo principal de este estudio consiste en valorar la utilidad de los datos geoquímicos en el reconocimiento de las fases de emersión. Para ello, se han seleccionado de una parte tres tipos de materiales recientes (travertinos, falsas agatas y espeleotemas), y de otra parte materiales carbonatados depositados (o precipitados) en relación con etapas de emersión acaecidas durante el mesozoico en el margen continental sudiberico. Sobre los tres grupos de travertinos muestreados, principalmente, las mayores variaciones isotopicas se constatan en el 13c y vienen definidas en unos casos por la mayor contribución del co2 procedente de la atmosfera del suelo, producido por la descomposición de la materia orgánica o por la respiración radicular de las plantas, y en otros casos por la mayor contribución del co2 atmosférico y del co2 derivado de la disolución de rocas carbonatadas. sobre las falsas agatas los valores isotopicos obtenidos son muy diferentes a los suministrados por las rocas encajantes donde estos se enclavan, por lo que se deduce que aunque su origen es por disolución y precipitación de estas, las condiciones genéticas en ambos casos fueron absolutamente distintasTesis Universidad de Granada. Departamento de Estratigrafía y Paleontologí

Reverse pseudo-gours: a new sub-type of folia observed in the Nerja Cave (SE Spain)

A new sub-type of folia named “reverse pseudo-gour” has been observed and described in the Nerja Cave, southern Spain. It consists of fairly vertical, thin barriers (about 5 mm high and 2 mm thick) that develop on the underside of a sub-horizontal surface (shelfstone) and grow in the opposite direction to normal gours (rimstone dams), generating sinuous shapes. Their mineral composition is essentially calcium carbonate, although globular aggregates composed of clay and phosphate minerals have also been identified. The genesis and evolution of these reverse pseudo-gours occur just at the air-water interface and are controlled by (1) the sub-horizontality of the surface on which they develop, (2) scarce to very scarce calcite supersaturation, and (3) progressive and slow lowering of the water level. Thus, reverse pseudo-gours represent the shape limit to which a folia reaches when its development occurs just below a nearly horizontal ceiling and the feeding water saturation is extremely low. Although this new sub-type of folia has only been observed in the Nerja Cave, it is highly probable that it exists in several other caves around the world because the factors controlling its development are not very strict

Reverse pseudo-gours: a new sub-type of folia observed in the Nerja Cave (SE Spain)

A new sub-type of folia named “reverse pseudo-gour” has been observed and described in the Nerja Cave, southern Spain. It consists of fairly vertical, thin barriers (about 5 mm high and 2 mm thick) that develop on the underside of a sub-horizontal surface (shelfstone) and grow in the opposite direction to normal gours (rimstone dams), generating sinuous shapes. Their mineral composition is essentially calcium carbonate, although globular aggregates composed of clay and phosphate minerals have also been identified. The genesis and evolution of these reverse pseudo-gours occur just at the air-water interface and are controlled by (1) the sub-horizontality of the surface on which they develop, (2) scarce to very scarce calcite supersaturation, and (3) progressive and slow lowering of the water level. Thus, reverse pseudo-gours represent the shape limit to which a folia reaches when its development occurs just below a nearly horizontal ceiling and the feeding water saturation is extremely low. Although this new sub-type of folia has only been observed in the Nerja Cave, it is highly probable that it exists in several other caves around the world because the factors controlling its development are not very strict.This study has been financed by the Nerja Cave Foundation, coordinated by its Research Institute and authorized by the Consejería de Cultura (Junta de Andalucía). This study is also a contribution to the RNM-308 Research Group of the Junta de Andalucía and to the Projects PID2021-125619OB-C21, PID2021-125619OB-C22, TED2021-130549B-I00 funded by MCIN/AEI/10.13039/50110001103