Factores que controlan la sedimentación en el humedal costero de Almenara: análisis geoquímico y estratigráfico.

La utilización conjunta de análisis sedimentológico, secuencias y geoquímico apolicado a depósitos de lagunas costeras (marjales) es una herramienta potente para el análisis de las variaciones del nivel del mar y costeros (playas, deltas). La aplicación de dicha metodología en los depósitos del Marjall de Almenara (Castellón) permite identificar, a partir del análisis de facies y selcuencial, las variaciones en la lámina del agua del humedal mientras que el análisis de los datos geoquímicos permite relacionar dichas fluctuaciones con episodios de mayor o menor intrusión sallina que pueden relacionarse con variaciones observados con los de otras áreas del Mediterráneo español

Applied Archaeoseismology: identification of earthquake archaeological effects of the 1755 Lisbon earthquake in the surrounding areas of the pilot plant for CO2 injection at Hontomín (Burgos, Spain)

La planta piloto de inyección de CO2 de Hontomín (Burgos) es la única planta de inyección en tierra en Europa. Para el desarrollo de este tipo de plantas de inyección son necesarios los estudios de los posibles efectos de terremotos que puedan afectarles. La falta de estudios de neotectónica en esta zona de la meseta norte de España hace necesario obtener datos sobre terremotos antiguos en esta zona. Los efectos de campo lejano del terremoto de Lisboa en Burgos pueden contribuir al conocimiento del comportamiento sísmico del terreno en caso de la ocurrencia de eventos similares. Hemos seleccionado principalmente construcciones románicas para obtener la dirección media de movimiento del sustrato generada por el terremoto de Lisboa en esta zona. Los resultados preliminares indican una dirección media de movimiento NE-SO. Las trayectorias de deformación obtenidas son refractadas por las fallas principales de la zona, variando su orientación para disponerse perpendiculares a estas.The pilot plant for CO2 injection at Hontomín (Burgos) is the only injection plant onshore in Europe. In the development of this type of injection plants it is necessary to study the effect of possible earthquakes that may affect it. The lack of neotectonic studies in this area of central Spain make necessary obtain data of ancient earthquakes that affected this territory. The far field effect of the Lisbon earthquake in Burgos can contribute to the knowledge on the ground behaviour in case of events of similar characteristics. We select the mainly Romanesque buildings to obtain the mean ground movement direction generated by the Lisbon earthquake in this area. The preliminary results show a mean direction of ground movement NE-SW. The strain trajectories are reflected by the main faults of the zone, varying its orientation to be oriented perpendicular to the main faults.Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEUnión Europea. Horizonte 2020Ministerio de Economía y Competitividad (MINECO)/FEDERInstituto Geológico y Minero de España (IGME)pu

An active tectonic field for CO2 storage management: the Hontomín onshore case study (Spain)

One of the concerns of underground CO2 onshore storage is the triggering of induced seismicity and fault reactivation by the pore pressure increasing. Hence, a comprehensive analysis of the tectonic parameters involved in the storage rock formation is mandatory for safety management operations. Unquestionably, active faults and seal faults depicting the storage bulk are relevant parameters to be considered. However, there is a lack of analysis of the active tectonic strain field affecting these faults during the CO2 storage monitoring. The advantage of reconstructing the tectonic field is the possibility to determine the strain trajectories and describing the fault patterns affecting the reservoir rock. In this work, we adapt a methodology of systematic geostructural analysis to underground CO2 storage, based on the calculation of the strain field from kinematics indicators on the fault planes (ey and ex for the maximum and minimum horizontal shortening, respectively). This methodology is based on a statistical analysis of individual strain tensor solutions obtained from fresh outcrops from the Triassic to the Miocene. Consequently, we have collected 447 fault data in 32 field stations located within a 20 km radius. The understanding of the fault sets’ role for underground fluid circulation can also be established, helping further analysis of CO2 leakage and seepage. We have applied this methodology to Hontomín onshore CO2 storage facilities (central Spain). The geology of the area and the number of high-quality outcrops made this site a good candidate for studying the strain field from kinematics fault analysis. The results indicate a strike-slip tectonic regime with maximum horizontal shortening with a 160 and 50◦ E trend for the local regime, which activates NE–SW strike-slip faults. A regional extensional tectonic field was also recognized with a N–S trend, which activates N–S extensional faults, and NNE–SSW and NNW– SSE strike-slip faults, measured in the Cretaceous limestone on top of the Hontomín facilities. Monitoring these faults within the reservoir is suggested in addition to the possibility of obtaining a focal mechanism solutions for microearthquakes (M < 3)This work has been partially supported by the European Project ENOS: ENabling Onshore CO2 Storage in Europe, H2020 Project ID: 653718 and the Spanish project 3GEO, CGL2017-83931-C3-2-P, MICIU-FEDE

Radon (222Rn) outgassing in San Juan volcanic tubes during the Cumbre Vieja eruption 2021, and preliminary values in the newly volcanic tubes.

During the eruption at Cumbre Vieja ridge (La Palma, Canary Islands, 2021) a radon (222Rn) detector (CORENTIUM Pro alpha particles counter) was emplaced inside the Las Palomas lava tube (San Juan eruption, 1949). In addition, a CO2 meter logger was emplaced to determine relationships between the 2021 eruption and radon plus CO2 inner fluxes. There is a geostructural relationship between the 1949 and 2021 eruptions, probably connected by a previous fault, shown the volcanic vents¿ alignment trending NW-SE. In October 2021, the radon and CO2 loggers were moved to the upper part of the lava tube, in the San Juan volcanic vent (Llano del Banco hollow dyke). Once the eruption ended (in early 2022) both loggers were placed in one newly formed lava tube, and data will be collected in February 2023. Preliminary results show daily average radon values ranging between 2 - 9 Bq/m3, although sporadic peaks of about 270 and 650 Bq/m3 were recorded related to volcano-tectonic earthquakes and volcanic intensity. In general, basaltic eruptions of alkaline affinity show low radon values due to the low concentration in the magma body of uranium and related chemical elements (Th, Ra, etc.). Geochemical analysis of emitted lavas shows a U concentration of about 1 to 5 ppm (g/g) and Th 9.5 ppm. Summer values of Rn increased up to 3 KBq/m3, related to the climate conditions instead of volcanic activity

Field deployment of a man-portable stand-off laser-induced breakdown spectrometer: A preliminary report on the expedition to the Cumbre Vieja volcano (La Palma, Spain, 2021)

This paper reports on the expedition to the Cumbre Vieja volcano (Canary Islands, Spain) in November 2021 to assess stand-off laser-induced breakdown spectroscopy for real-time measurements of the lava streams from a safe point. The paper provides insight on the analytical approach to the problem, the rationale of the instrument design and construction carried out in three weeks, the experience with the new-born instrument at the volcano and the preliminary results. Despite the subtle spectral differences among the samples and the signal variability induced by the strong wind gusts at site, a statistical approach to data processing such as PCA, made possible to extract sufficient information and provide a robust classification tool.We express our sincere gratitude to the Spanish Unidad Militar de Emergencias (UME) for providing essential support, security, and expertise at the field. We would like to thank Carlos Malag ́on (Astro- shop, M ́alaga, Spain) for donating the telescope used in the stand-off LIBS instrument, to the personnel of the Chemical Analysis Area and the Machine Shop of the Central Facility for Research Support (SCAI-UMA) and to Profs. E.R. Losilla and A. Cabeza (Dept. Química Inorgánica, Cristalografía y Mineralogía, UMA) and D. Marrero (Dept. Física Aplicada I, UMA) for their valuable comments and advice with the surrogate samples. This work has been partially supported by the I Plan Propio de Investigaci ́on de la Universidad de M ́alaga, the Extraordinary Funding (RD 1078/2021, 7th December, Núm. 293 Sec. I. P ́ag. 150,995) and PID2020-113407RB-I00 granted by the Spanish Ministry of Science and Innovation (MICINN). Funding for open access charge: Universidad de Málaga / CBU

Structural Analysis and Active strain-field for Induced Seismicity in gas storage facilities: Hontomin study-case (SPAIN)

La determinación de las fallas capaces de disparar terremotos en zonas adyacentes con formaciones geológicas aptas para el almacenamiento profundo de gas, es una tarea que mitiga la ocurrencia de sismicidad inducida por operaciones subterráneas y movimiento de fluidos. Para ello, la determinación del campo de esfuerzos/deformación tectónicos activo ayuda a entender los patrones tridimensionales de fracturación cartografiados no solo en la zona, sino también en la propia roca almacén. Por este motivo, se presenta un protocolo de trabajo para la obtención del campo de deformación (σHmax, σhmin) que ayude a entender el papel de cada conjunto de fallas cartografiado. Para ello, aplicamos el Análisis Poblacional de fallas en dos zonas de influencia: 1) Campo cercano: 10 km de diámetro del almacenamiento y 2) Campo Lejano: 20 km de diámetro. Sobre estas zonas calculamos las trayectorias de deformación y llevamos a cabo una cartografía sistemática de fallas. Se presentan los resultados preliminares de Hontomín.The cartography of seismogenic active faults in adjacent areas of underground gas storage helps in the management for Induced Seismicity related to deep fluid movement and injection/extraction manoeuvres. In this sense, the determination of the Active Stress field into the area allows the understanding of the 3D fracture patterns and their role in earthquake occurrence. We introduce a protocol for study active tectonic stress by using the classical Structural Analysis based on brittle techniques. Accordingly, we have defined two different areas for studying: (1) Near field, 10 km of diameter from the Storage Site and (2) Far Field, 20 km diameter. Preliminary results for Hontomin site are presented.Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEUnión Europea. Horizonte 2020pu

Subfacies geoquímicas: una mejora en la caracterización de depósitos litorales (sondeo de Almenara, provincia de Castellón)

El estudio sedimentológico de un sondeo de 24 m realizado en el marjal de Almenara (provincia de Castellón), ha permitido diferenciar 8 niveles estratigráficos, sobre los que se ha realizado un estudio geoquímico de elementos mayores, trazas, S, Corg y Cinorg. La utilización de ambos análisis ha permitido determinar más adecuadamente las variaciones ambientales registradas en el sedimento. Además, la realización de un análisis de componentes principales (PCA) tanto sobre el total del sondeo como sobre cada uno de los niveles estratigráficos por separado, permite la observación de otros procesos que son particulares a cada uno de los medios de sedimentación. [ABSTRACT] The sedimentologic analysis made in a core located in Almenara marsh (Castellón province) of 24 m has allowed to determine 8 stratigraphic levels, in which an high-resolution geochemical analysis has also been performed (major and trace elements, S, TIC and TOC).The use of both analyses allowed an accurate description of the environmental changes recorded in the sediment. In addition, using the principal component analysis (PCA) in the total core and in each of the stratigraphic levels, has allowed to recognize other processes which are particular to each sedimentation environment

Geochemical analysis of the holocene record of the Almenara marsh. Eustatic changes

La utilización conjunta del análisis secuencial y geoquímico aplicado a depósitos de lagunas costeras (marjales) es una herramienta potente para el análisis de las variaciones del nivel del mar durante los últimos milenios. La aplicación de dicha metodología en los depósitos del Marjal de Almenara (Castellón) permite identificar, las variaciones en la lámina de agua del humedal y de la intrusión salina que pueden relacionarse con variaciones relativas del nivel del mar. El estudio ha dado como resultado tres momentos de ascenso relativo del nivel del mar (ca. 5300 años BP, ca.3500 años BP y ca. 2000 años BP).Sequential and geochemical analysis applied on marsh deposits are a powerful tool for the interpretation of sea level changes during the last millennia. The application of that methodology on the Almenara Marsh deposits (Castellón, E Spain) reveals the fluctuations of the marsh water-table and the variations the marine water wedge of the groundwater that can be related to changes in the relative sea level. The study permits to recognize three moments of relative high sea level (ca. 5300 years BP, ca. 3500 years BP and ca. 2000 years BP).Depto. de Geodinámica, Estratigrafía y PaleontologíaFac. de Ciencias GeológicasTRUEpu