Articles publicats en revistes (Mineralogia, Petrologia i Geologia Aplicada)

URI permanent per a aquesta col·leccióhttps://diposit.ub.edu/handle/2445/8477

Estadístiques

Examinar

Enviaments recents

Mostrant 1 - 20 de 1005
  • logoOpenAccessArticle
    Assessment of groundwater quality using hydrochemical process, GIS and multivariate statistical analysis at central Rif, North Morocco
    (Springer Verlag, 2024-09-01) Alitane, Abdennabi; Chahban, Mohamed; Boughrous, Ali Ait; Benyoussef, Said; Arabi, Mourad; El Yousfi, Yassine; Makkaoui, Mohamed; Gueddari, Hicham; El Ouarghi, Hossain; Abdaoui, Abdellali; Ghalit, Mohammad; Zegzouti, Younes Filali; Azirar, Maryam; Himi, Mahjoub
    This study investigated groundwater in the central Rif region of northern Morocco by analysing 55 water sampling points to assess its physicochemical and hydrogeochemical properties. Through hydrochemical analysis, GIS spatial exploration, and multivariate statistical analysis, a direct correlation was found between EC, TDS, and major ions, influencing overall water mineralization. The key findings included pH levels ranging from 6.10 to 8.52, EC from 828 to 4581 μS/cm, and varying concentrations of Ca2+, Mg2+, Na+, K+, HCO2–, Cl–, N–NO2–, and SO42–. Notably, TDS and TH ranged from 647.19–3609.36mg/L and 64.23–1051.24 mg/L, respectively, with a significant portion of samples exceeding WHO guidelines, particularly chloride (61.81%), sulfate (92.72%), and nitrate (12.72%) samples. The Piper diagram highlights sodium chlorides (Na–Cl) as the predominant chemical facies (70.9%), while the Gibbs diagram emphasizes the impact of evaporation on water chemistry dynamics. This study revealed the complex influence of geological and anthropogenic factors on groundwater quality,potentially leading to seawater intrusion in coastal aquifers. The observed high mineralization and hardness levels, in addition to mild alkalinity, pose public health risks, underscoring the need for continuous monitoring and sustainable management practices in coastal groundwater management to protect human health and the environment.
  • logoOpenAccessArticle
    The medieval stained glass in Catalonia: Girona cathedral
    (Elsevier, 2025-07-01) Pradell, Trinitat; Cañellas, Sílvia; Bonet, Jordi; Garcia Vallès, Maite; Santolària, Anna
    The production and distribution of stained glass in Mediterranean Europe during the Middle Ages remains inadequately

    understood. This article focuses on Catalonia, where local glass production is documented as early as the

    13th century, but little is known about the production of window glass. This study analyses a collection of stained

    glass fragments from Girona Cathedral, dating from the 13th to the 16th century, some of which is the work of

    renowned master glassmakers. The data obtained is compared with contemporary stained glass documented

    from other parts of Europe, and with a collection of 15th and 16th century archaeological window glass from

    Barcelona. The data is also contrasted with historical documentation on glass production in Catalonia. The findings

    reveal that the glass from Girona from the 13th and 14th centuries is of the potassium-lime type, similar to

    that produced in the workshops of north-western France. By the late 14th and 15th centuries, the composition

    aligns more closely with that of north-eastern France. In the 16th century, however, the glass changes to a sodalime

    composition, similar to the glass found in Barcelona, suggesting a transition from central European to

    Mediterranean sources, and indicates a change in the raw materials involving the use of soda-lime plant ash instead

    of potassium-lime forest ash. These results indicate that the production of window glass shifted from France

    to Barcelona at the close of the 15th century.

  • logoOpenAccessArticle
    Mineralogy, geochemistry and origin of karst bauxite deposits from the Reserva Fiscal Ávila, SW Dominican Republic
    ((UB). (ICTJA). (IDEA). (UAB). (CSIC), 2025-05-01) Domínguez-Carretero, Diego; Villanova de Benavent, Cristina; Torró i Abat, Lisard; Pujol Solà, Núria; Bover-Arnal, Telm; Mestre, Àngel; Aiglsperger, Thomas Hans; Ramírez, Australia; Rodríguez, Jesús; Espaillat, Julio; Proenza Fernández, Joaquín Antonio
    The energy transition, which aims to reduce carbon emissions and to slow down climate change, demands an ever-increasing supply of the so-called “critical metals”. Rare-earth elements and yttrium (REY) are among the most critical metals, as they are indispensable in most technologies associated with the generation and storage of renewable energy. In recent years there has been a growing interest in the potential of karst bauxites as non-conventional sources of REY and other critical metals such as Sc and Ga. The Sierra de Bahoruco (SW Dominican Republic) contains the most REY-enriched karst bauxites globally. In view of the high potential for hosting important REY contents, the Dominican Republic government has declared the Reserva Fiscal Ávila (RFA), a state-owned area within the Sierra de Bahoruco for assessment and exploration of its REY resources. In this study, we present the first data on the mineralogy and composition of bauxitic rocks from the RFA. The bauxitic deposits comprise clayey bauxites and Fe-rich bauxites that are composed predominantly of Al-oxyhydroxides (gibbsite, boehmite and nordstrandite), kaolinite and Fe-oxyhydroxides. The bauxites are enriched in REY, with a median value of 1,310ppm and up to 2,542ppm, with a consistent enrichment in light REE (LREE) and Y compared to middle (MREE) and heavy REE (HREE). The positive correlation between the contents of REY and Th, and negative correlation with K, makes gamma-ray spectrometry an appropriate tool for the exploration. In addition, bauxitic rocks from the RFA contain significant Sc (up to 105ppm) and Ga (up to 54ppm) contents, and their extraction could potentially represent a substantial economic surplus to the revenue generated solely from the aluminum production. Based on the trace element geochemistry, we suggest that Karst bauxite deposits from the Reserva Fiscal Ávila bauxites from the RFA had a similar parental source to the soils and bauxites from Jamaica.
  • logoOpenAccessArticle
    Assessing preferential seepage and monitoring mortar injection through an earthen dam settled over a gypsiferous substrate using combined geophysical methods
    (Elsevier B.V., 2018-11-28) Himi, Mahjoub; Casado, Ismael; Sendrós Brea-Iglesias, Alex; Lovera Carrasco, Raúl; Rivero Marginedas, Lluís; Casas Bou, Albert
    For several decades the Sant Llorenç de Montgai reservoir has experienced different problems that could affect the safety of the engineering structure. For this reason, several corrective actions have been taken over the years. Here, we present a study involving complementary geophysical methods including electrical resistivity tomography, seismic refraction tomography and frequency-domain electromagnetic surveys. The analysis of the inverted electrical resistivity tomography cross-sections combined with the seismic refraction results and land subsidence monitoring data show the likely mechanism of abnormal seepage. The areas where mortar injections were applied as a corrective measure are also clearly delineated. In addition, the evolution of the state of the embankment has been established from two successive electrical resistivity tomography surveys in the last two decades. The results show areas where corrective mortar injections have been effective, while in other areas new abnormal seepage has been detected. The lithological heterogeneity of the bedrock, especially the dissolution of gypsum-rich rocks, induced subsidence effects and caused abnormal seepage in different areas along the embankment. Our results indicate how corrective solutions can be optimized to reduce the cost of corrective engineering interventions.
  • Article
    Middle Devonian–Carboniferous crustal differentiation promoted by hydrous plume-related magmatism along the Paleo-Pacific active margin: A case study of the Gashun Nuur Complex in the Mongolian Altai
    (Elsevier B.V., 2025-06-23) de Hoÿm de Marien, Luc; Janoušek, Vojtěch; Schulmann, Karel; Hanžl, Pavel; Míková, Jitka; Hora, John M.; Racek, Martin; Lexa, Ondrej; Sukhbaatar, Turbold; Buriánek, David; Aguilar Gil, Carmen María
    Petrology, whole-rock geochemistry, Sr–Nd isotopic data, and zircon U–Pb geochronology of magmatic rocks from Gashun Nuur Complex (Tseel Sum, Mongolian Altai) confirm catastrophic mid–late Devonian–Tournaisian (c. 385–350  Ma) mantle melting. Early (c. 385  Ma), scattered, large (∼ 100  m across) metagabbroic bodies carry a weak subduction-like signature (elevated contents of Large Ion Lithophile Elements – LILE, depletion in High Field Strength Elements – HFSE, high EiNd

     of + 3.9 to + 7.0, unradiogenic 87Sr/86Sri of 0.7036–0.7044). Younger (c. 375–350  Ma) Fe-poor and Fe-rich dismembered amphibolite sheets show an EMORB character typical of melts resulting from the interaction of a subduction-modified depleted lithospheric mantle with a mantle plume (moderate LILE and HFSE, highly positive EiNd

     of + 6.4 to + 9.2, variable 87Sr/86Sri of 0.7037–0.7068). Their chemistry marks the arrival of a mantle plume in an active margin setting far behind the magmatic arc. The Gashun Nuur Complex belongs to a vast (> 300,000  km2) mosaic of Devonian magmatic provinces which encompass the Altai suprasubduction, Altai–Sayan intracontinental and Mongol–Okhotsk oceanic domains. The studied middle Devonian–Tournaisian magmatic event is interpreted as the surface expression of hydrous plume(s) developed above a dehydrating flat-slab resting upon the lower mantle, at the mantle transition zone. The flat slab favoured the retreat of the trench causing extension in the overriding lithosphere. In the Gashun Nuur Complex, heat and fluids from mantle-derived intrusions induced extensive partial melting of a fertile Cambrian–Ordovician volcanic–sedimentary accretionary wedge, promoting a wide-rift mode of extension. Ascent and emplacement of granitic magmas to the middle crust left a still partially hydrated lower crust with an intermediate composition. This process of crustal differentiation may have played an important role in the stratification and stabilisation of the continental crust through the Earth’s history.

  • logoOpenAccessArticle
    How to remove toxic metal-rich road dust from urban environments? A new eco-friendlyremediation approach.
    (Sociedad Española de Mineralogía, 2025-01-15) Navarro Ciurana, Dídac; Garcia Vallès, Maite
    Ambient particulate matter pollution, which can be accumulated on urban roads, is one of the global modern society challenges (WHO, 2016). This road dust is constituted by different fractions of geogenic and anthropogenic particles, which commonly act as a potentially toxic elements (PTEs) temporary storage. In low-income countries, long-term exposure to traffic-generated dust was estimated to cause every year 1.5 to 2 million premature deaths, mostly children and women. In high- and middle-income countries, there is also an increasing awareness and concern of the potential adverse impacts of dust on health (Navarro-Ciurana et al., 2023). The current methods applied to reduce road dust are based on: i) their recovery by sweep cleaning and subsequent accumulation in wastelands, increasing the local pollution in these areas, and ii) their street elimination with water cleaning, which produce an increase of dissolved metals on urban runoff and residual waters. Consequently, remediation tools to efficiently eliminate the road dust’s PTEs from the environment are urgently needed. Vitrification of polluted soils has been applied as an in- and ex-situ remediation procedure, where they are used as raw material in the glass manufacture (Roca et al., 2021). However, this promising technique has not yet been applied to road dust. We present here for the first time the application of the vitrification technique of heavy metal-polluted roadside dust as an eco-friendly remediation solution. This study is based on road dust from Barcelona Province (Badalona city) to illustrate their potential as a new raw material for glass production. This could be an eco-friendly solution to attenuating the environmental pollution problem and prejudicial health impacts in a sustainable circular economy context, as well as to obtain an economic benefit. 
  • Article
    Isotope record of Aptian third-order sea-level trends in platform margin carbonates: implications for sequence stratigraphic analysis
    (Society for Sedimentary Geology (SEPM), 2025-04-16) Muñoz López, Daniel; Koeshidayatullah, Ardiansyah; Bover-Arnal, Telm; Herlambang, Adhipa; Martín, Juan Diego (Martín Martín); Salas, Ramon (Salas Roig); Humphrey, John D.; Al-Ramadan, Khalid
    In ancient carbonate systems, establishing relationships among sea-level fluctuations, carbonate-factory productivity, and carbonate geochemistry is challenging due to complex depositional and diageneticoverprinting. The Aptian platform carbonate succession from the western Maestrat Basin, in Spain, serves as anideal example for potentially linking these processes, particularly establishing the relationships between isotoperecords (d18O and d13C) and third-order sea-level trends with implications for sequence stratigraphy. Thissuccession is biostratigraphically well constrained and comprises two depositional sequences that were controlledby a major relative sea-level fall and a subsequent rise. These depositional sequences exhibit stratal terminationsand stacking patterns, enabling the establishment of a well-defined sequence stratigraphic framework comprisingfour systems tracts and their key bounding stratigraphic surfaces. The analytical results reveal that both d18Oand d13C values outline distinct temporal trends, which can be correlated with specific third-order stages ofrelative sea-level fluctuations. The transgressive and highstand systems tracts exhibit the most positive d13Cvalues (up to 15%) and the least negative d18O values (up to–1.8%). This range, similar to values of carbonatesin equilibrium with Cretaceous seawater, d13C and d18O values from 12% to 15% and from–2% to–5%,respectively, likely reflects the marine influence on the isotope values during the stage of high relative sea level. Incontrast, the forced regressive and lowstand intervals exhibit less positive d13C values (reaching 10.5%) andsignificantly more negative d18O values (around–6.1%), interpreted as the influence of soil-derived organicmatter and meteoric waters, respectively, during stages of lower relative sea level. Furthermore, the sedimentarysuccession records a decreasing trend of d13C and d18O values towards the sequence boundary, which marks thelowest point of relative sea level. This study underscores the potential of carbonate platforms to recordgeochemical signals that can be directly correlated with different third-order stages of relative sea-levelvariations. In addition, this framework allows for linking and predicting the potential fluid–rock interactionprocesses in each systems tract. The proposed approach could offer a predictive framework for characterizingcarbonate reservoirs and other carbonate platform successions with poorly defined sequence-stratigraphicframeworks elsewhere.
  • logoOpenAccessArticle
    Granitoid Metasomatism and Giant Quartz Vein Formation by Mineral Replacement: Insights from the Canigó Massif, Eastern Pyrenees
    (Oxford University Press, 2025-02) González-Esvertit, Eloi; Canals i Sabaté, Àngels; Prieto-Torrell, Claudia; Bons, Paul D.; Llorens, Maria-Gema; Casas Tuset, Josep Maria; Aguilar Gil, Carmen María; Neilson, J.; Elburg, Marlina A.; Gómez Rivas, Enrique
    Metasomatism is a ubiquitous process in the Earth’s crust, exerting major controls on fluid, heat and mass transfer and rock deformation, and is commonly constituted by mineral replacement reactions. Different types of metasomatism may coexist and/or successively conceal each other in a given area. Deciphering the geochemical behaviour, regional extent and mineralogical changes of multi-stage metasomatism can be difficult because of the overprinting of successive events and their frequent relationship with deformation. Here, we investigate granitoid metasomatism, namely silicification, feldspathisation and sericitisation, in the Variscan basement rocks of the Canigó Massif (Eastern Pyrenees, SW Europe), which is spatially related to Giant Quartz Veins (GQVs) tens of metres wide and several kilometres long. Unaltered and altered granitic orthogneisses derived from Ordovician intrusives and late-Variscan granitoids, as well as GQV occurrences, are studied across scales through structural and textural characterisation, whole-rock geochemistry and Electron Backscatter Diffraction (EBSD). Geochemical analyses are further compared with a new database including more than 600 unaltered granite and orthogneiss samples from the Pyrenees and the Catalan Coastal Ranges (SW European Variscan Belt). Results show that silicification, the dominant metasomatic process, was related to regional-scale shear zones and contributed to form GQVs through mineral replacement. This is confirmed at the macro- (km), meso- (m–cm) and micro-scale (μm) by relict fabrics, mineral phases and structural features of the precursor rocks within veins, by a progressive depletion of all major and trace elements, except silica, in rocks sampled along decreasing distances from GQV outcrops, and by the localisation of mylonitic deformation along GQVs. Feldspathisation and sericitisation are, in contrast, restricted to specific sectors and exposed as albitite, trondhjemite and pale green mica-rich outcrops. It is suggested that most of the exposed areas of the studied GQVs are, accordingly, not veins sensu stricto but metasomatic products where the original fabrics and features of precursor rocks were overprinted during coupled deformation and Si-metasomatism. Results presented here have major implications for the scale and geochemical behaviour of multi-metasomatic events, as well as on the kinetics of mineral replacement processes leading to changes in the physicochemical properties of crustal rocks.
  • logoOpenAccessArticle
    Upper Barremian−lower Aptian charophyte biostratigraphy from Arrifes section (Algarve Basin, Southern Portugal): correlation with dinoflagellate cyst biostratigraphy
    (Elsevier Ltd., 2023-05-18) Callapez, Pedro; Pérez Cano, Jordi; Pereira, Hélder J.R.; Mendes, Marcia; Pereira, Zélia; Fernades, Paulo
    The Arrifes section (Algarve Basin, Southern Portugal) has been studied from the viewpoint of charophyte biostratigraphy. The previous sedimentological studies in this section showed that it is built of the interbedding of continental and marine facies that contain both marine and continental palynomorphs (pollen, spores, and dinoflagellates), providing an excellent sedimentary context to perform direct correlations between marine and continental domains. In the present work, the identified charophyte biozones have been correlated with dinoflagellate biozones previously recognized in the Arrifes section, being the first time that these two biochronologies can be directly correlated. From the charophyte biostratigraphy viewpoint, two assemblages are distinguished. The older one is found between 65 and 135 meters of the stratigraphic section, and it is composed of the species Echinochara lazarii, Atopochara trivolvis var. triquetra, A. trivolvis var. trivolvis, Clavator grovesii var. jiuquanensis, Clavator harrisii var. harrisii, C. harrisii var. reyi, and C. harrisii var. zavialensis. This assemblage belongs to the upper Barremian-lower Aptian Clavator grovesii var. jiuquanensis Eurasian biozone and also to the Ascidiella cruciata-Pseudoglobator paucibracteatus European biozone and it is described in beds with the dinoflagellate cyst Subtilisphaera scabrata (lower to lowermost late Barremian) and Odontochitina operculata (from upper Barremian upwards). The younger charophyte assemblage is found between 135 and 155 metres of the stratigraphic section, and it is composed of the species A. trivolvis var. trivolvis, Clavator grovesii var. corrugatus, Clavator harrisii var. harrisii, C. harrisii var. reyi, and C. harrisii var. zavialensis. This assemblage belongs to Clavator grovesii var. corrugatus biozone, previously assigned to upper Aptian (Clavator grovesii var. lusitanicus biozone). However, in the Arrifes section, this assemblage is found in beds assigned to the dinoflagellate cyst Odontochitina operculata (from upper Barremian-lower Aptian). The direct correlation of the base of the C. grovesii var. corrugatus biozone with the dinoflagellate cyst O. operculata, indicates that the base of the Clavator grovesii var. corrugatus biozone is in the upper lower Aptian, which is slightly older than was previously suggested, and it is extended until the middle Albian.
  • logoOpenAccessArticle
    Mobilization pilot test of PCE sources in the transition zone to aquitards by combining mZVI and biostimulation with lactic acid
    (Elsevier B.V., 2023-03-05) Puigserver Cuerda, Diana; Herrero Ferran, Jofre; Carmona Pérez, José Ma. (José María)
    The potential toxic and carcinogenic effects of chlorinated solvents in groundwater on human health and aquatic ecosystems require very effective remediation strategies of groundwater contaminated to achieve the low legal cleanup targets required. The transition zones between aquifers and bottom aquitards occur mainly in prograding alluvial fan geological contexts. Hence, they are very frequent from a hydrogeological point of view. The transition zone consists of numerous thin layers of fine to coarsegrained clastic fragments (e.g., medium sands and gravels), which alternate with finegrained materials (clays and silts). When the transition zones are affected by DNAPL spills, free-phase pools accumulate on the less conductive layers. Owing to the low overall conductivity of this zone, the pools are very recalcitrant. Little research has been done on the field-scale application of the different remediation techniques regarding transition zones. Injection of iron microparticles has the disadvantage of the limited accessibility of this reagent to reach the entire source of contamination. Biostimulation of indigenous microorganisms in the medium has the disadvantage that few of the microorganisms are capable of complete biodegradation to total mineralization of the parent contaminant and metabolites. A field pilot test was conducted at a site where a transition zone existed in which DNAPL pools of PCE accumulated. In particular, the interface with the bottom aquitard was where PCE concentrations were the highest. In this pilot test, a combined strategy using ZVI in microparticles and biostimulation with lactate in the form of lactic acid was conducted. Throughout the test it was found that the interdependence of the coupled biotic and abiotic processes generated synergies between these processes. This resulted in a greater degradation of the PCE and its transformation products. With the combination of the two techniques, the mobilization of the contaminat source of PCE was highly effective.
  • logoOpenAccessArticle
    Fabrication of glass-based products as remediation alternative for contaminated urban soils of Barcelona
    (Elsevier B.V., 2021-12-15) Roca Pascual, Núria; Garcia Vallès, Maite; Alfonso Abella, María Pura
    Contaminated soils from an area previously occupied by a metal smelting industry of Barcelona city were used as raw material for making glass. Vitrification was investigated as a possible remediation technique. The main pollutants in these soils are Cu, Pb and Zn. Glass was formulated using 80 wt% of soil and 20 wt% of Na2CO3. The mixture was molten at 1450 °C. Crystallisation temperatures, obtained by Differential Thermal Analysis, were 790 °C, 842 °C and 879 °C. Nepheline, diopside and rhönite crystallized from glass treated at exothermal peaks. The endothermic peak at 1259 °C corresponds to the melting temperature. Glass transition temperature, determined by dilatometry was 632 °C. Viscosity-temperature curve was used to calculate the relevant temperatures for the process. The conformation range is between 995 °C and 1298 °C, and the workability interval ranges from 1293 °C to 1302 °C. The contents of the elements leached from the glass are well below the limits established by the European legislation. Thus, the vitrification is an effective remediation technique for contaminated soils.
  • logoOpenAccessArticle
    Bioremediation Potential in Recalcitrant Areas of PCE in Alluvial Fan Deposits
    (World Academy of Science, Engineering and Technology (WASET), 2019-03-03) Herrero Ferran, Jofre; Puigserver Cuerda, Diana; Nijenhuis, I.; Kuntze, K.; Carmona Pérez, José Ma. (José María)
    In the transition zone between aquifers and basal aquitards, the perchloroethene (PCE)-pools are more recalcitrant than those elsewhere in the aquifer. Although biodegradation of chloroethenes occur in this zone, it is a slow process and a remediation strategy is needed. The aim of this study is to demonstrate that combined strategy of biostimulation and in situ chemical reduction (ISCR) is more efficient than the two separated strategies. Four different microcosm experiments with sediment and groundwater of a selected field site where an aged pool exists at the bottom of a transition zone were designed under i) natural conditions, ii) biostimulation with lactic acid, iii) ISCR with zero-value iron (ZVI) and under iv) a combined strategy with lactic acid and ZVI. Biotic and abiotic dehalogenation, terminal electron acceptor processes and evolution of microbial communities were determined for each experiment. The main results were: i) reductive dehalogenation of PCE-pools occurs under sulfate-reducing conditions; ii) biostimulation with lactic acid supports more pronounced reductive dehalogenation of PCE and trichloroethene (TCE), but results in an accumulation of 1,2-cis-dichloroethene (cDCE); iii) ISCR with ZVI produces a sustained dehalogenation of PCE and its metabolites iv) combined strategy of biostimulation and ISCR results in a fast dehalogenation of PCE and TCE and a sustained dehalogenation of cisDCE. These findings suggest that biostimulation and ISCR with ZVI are the most suitable strategies for a complete reductive dehalogenation of PCE-pools in the transition zone and further to enable the dissolution of dense non-aqueous phase liquids.
  • logoOpenAccessArticle
    Thermal studies on the lower Carboniferous basins of Khenifra and Qasbat-Tadla, Morocco: What do they teach us about the pre-Variscan stages in NW Africa?
    (Elsevier, 2024-11-01) Cózar, Pedro; Lepretre, Remì; El Houicha, Mohamed; Schito, Andrea; Ouchaou, Rachid; Chopin, Francis
    Within the Variscan Belt of Morocco, the Central Massif preserves Early Carboniferous rift basins. The Lower Carboniferous Khenifra and Qasbat-Tadla basins are aborted rifts, developed just before the Variscan orogenesis in Morocco that occurred during the Pennsylvanian-Cisuralian in NW Africa. Due to both weak inversion of these basins during the Variscan orogeny and limited burial afterwards, these basins offer the opportunity to study the Early Carboniferous pre-orogenic thermal regimes. In the Khenifra basin, 77 samples collected across the basin and its basement's boundaries, allowed the determination of the maximal temperature reached during the rocks burial by means of Raman spectroscopic analyses. The Ordovician basement shows mean temperatures between 230 and 300 °C whereas the upper Visean/Serpukhovian infill has a wide range, from temperatures <160 °C to 250–260 °C. This thermal variation within the basinal series has been evidenced from west to east and cannot have been acquired during the Variscan events. The acquisition of these maximal temperatures occurred between Late Devonian to Upper Visean/Serpukhovian and is thought to result from the formation of an extended rift. In the Qasbat-Tadla basin, Rock-Eval data from Ordovician to Devonian source-rocks indicate significantly lower maximal temperatures reached by pre-Carboniferous samples that are within the oil window. Our results are in favor of a heterodox model for the Variscan belt in Morocco and NW African in general, suggesting that no pre-Variscan compressional events are needed. Instead, the development of the intraplate Variscan belt in NW Africa was permitted through the development of hot and weak Lower Carboniferous basins, subsequently inverted in a far-field stress field. The striking thermal differences between the Khenifra and Qasbat-Tadla basins suggest that important tectonic segmentation must have shaped the area during the Early Carboniferous extensional phase.
  • logoOpenAccessArticle
    Graphitization of Neoproterozoic sedimentary marbles in The Aird, Scottish Highlands
    (Geological Society of London, 2024-11-26) Parnell, John; Heptinstall, Eleanor A.; Schito, Andrea; Boyce, Adrian J.; Armstrong, Joseph G.T.; Muirhead, David
    Graphite occurs in Neoproterozoic (probable Loch Ness Supergroup) marbles of The Aird, in the Northern Highland Terrane, Scotland. The graphite occurs particularly in association with phlogopite mica, and also with other micas and Mg-chlorite. Although the graphite–phlogopite association is recorded widely elsewhere in mantle-derived rocks, our data suggest graphite at The Aird does not have a mantle origin. The carbon isotopic composition of the graphite ( 13C: −1.6 to 0.4‰) indicates that graphitization occurred from a CO2-rich fluid associated with decarbonation or devolatilization reactions of a carbonate–silicate protolith. Graphite–phlogopite-bearing marbles in The Aird underwent extensive brecciation and hematite deposition that preceded carbon-rich, mantle-derived (carbonatite) fluids. Pyrite in veins within The Aird marble has a sulfur isotope composition depleted in 34S (−16.6 to −15.5‰), suggesting a biogenic origin. Elsewhere in The Aird and in surrounding fenitized rocks, 34S-enriched pyrite has sulfur isotope compositions between 6.1 and 7.7‰, outside the sulfur isotopic composition range of most carbonatite-hosted pyrite, suggesting that pyrite veining is likely to have been influenced by crustal fluid–rock interactions. The observations show that if the protolith has a carbonate–silicate composition, a graphite–phlogopite association can form without the need for mantle-derived fluids.
  • logoOpenAccessArticle
    Active fault control on Plio-Quaternary gypsum veins systems (the Galera Fault, S Spain)
    (Sociedad Geológica de España, 2024-07-02) Medina-Cascales, I.; Carrazana, A.; Gómez Rivas, Enrique; Alfaro, P.; García-Tortosa, F.J.; Martín-Rojas, I.
    Gypsum veins were formed during the Pliocene and Pleistocene within the damage zone of the active,left-lateral Galera Fault (central Betic Cordillera, S Spain). Structural analysis reveals that vein distributionand geometry are controlled by fault activity. Veins grew in a band around the fault, which width varies according to the complexity of the fault array. Vein size increases near main fault strands. There is a closerelationship between vein orientation and the arrangement, kinematics, and interactions of the faultsconforming the fault zone. Veins are aligned with fractures accommodating transtensional deformationwithin the strain field of the fault. However, vein orientation is highly sensitive to small strain fieldvariations due to the presence of local structures resulted from fault displacement. Rotation of some vein sets indicates that vein growth initiated shortly after the deposition of the Plio-Pleistocene host rocks, simultaneously to fault activity. Early vein sets formed perpendicular to bedding under shallow burial conditions, conditioning the growth of future veins with different orientations.
  • logoOpenAccessArticle
    The Iberian thermal lithosphere and perspectives on deep geothermal studies
    (Sociedad Geológica de España, 2024-07-02) Torne, M.; Jiménez Munt, Ivone; Negredo, A.M.; Fullea, J.; Vergés i Masip, Jaume; Marzán, I.; Alcalde Sicilia, Judit; Gómez Rivas, Enrique; García de la Noceda, C.
    Las fuentes de energía renovable son clave para la transición hacia un sistema de energía limpia. Entre ellas, la energía geotérmica tiene una producción cuya efectividad requiere conocer la distribución de la temperatura y la circulación de fluidos en profundidad y las propiedades litológicas y petrofísicas de la corteza. Basándonos en resultados publicados, analizamos la profundidad del Límite Litósfera–Astenosfera (LAB, en inglés) de la Península Ibérica y la distribución de la temperatura a profundidades de 5, 10 y 20 km y en la Moho. A 5 km, la temperatura supera los 110 °C con anomalías locales (> 130 °C) localizadas en el Macizo Ibérico y en las zonas volcánicas Cenozoicas del SE y NO. A 10 y 20 km de profundidad, se observa un patrón similar con T superiores a 190 °C y 350 °C, respectivamente. A 20 km de profundidad, las anomalías superiores a 500 °C delimitan las zonas volcánicas Cenozoicas. A profundidades de la Moho, la temperatura varía entre 450 y 800 °C, con zonas calientes principalmente a lo largo del Macizo Ibérico y las zonas volcánicas Cenozoicas. No se observan anomalías litosféricas que pueda generar altas temperaturas a poca profundidad, aunque sí muestran un potencial de explotación aceptable a profundidades intermedias.
  • logoOpenAccessArticle
    Characterization of the Castellón Sandstones Formation (Late Miocene) in the Valencia Trough. Implications for the subsurface CO2 storage
    (Sociedad Geológica de España, 2024-07-02) Gil-Ortiz, M.; Gómez Rivas, Enrique; Alcalde Sicilia, Judit; Cabello López, Patricia; Zamora, Gonzalo
    La Formación Areniscas de Castellón está formada por depósitos deltaicos correspondientes a la progradación del paleo-delta del Ebro durante el Mioceno superior. La caracterización estratigráfica y sedimentológica de estos depósitos, mediante datos de subsuelo, ha probado que esta formación estaría dominada principalmente por depósitos de frente deltaico y plataforma interna, con presencia de depósitos de llanura deltaica en la zona más próxima al actual delta del Ebro. Los patrones de apilamiento observados en pozos dentro del área de estudio, así como la evolución del quiebre entre la plataforma y el talud continental observados en sísmica, muestran una tendencia progradante para buena parte de esta formación, en contraste con la tendencia retrogradante actual del delta. Esta formación está limitada a techo por la Superficie Erosiva del Messiniense, una discordancia desencadenada por la caída del nivel del mar durante el Messiniense que favoreció la creación de un característico paleorelieve. Durante el Plioceno, tras la reconexión entre el Mar Mediterráneo y el Océano Atlántico, una rápida subida del nivel del mar dio lugar a la fosilización de este paleorelieve mediante la sedimentación de una potente unidad de arcillas sobre los depósitos arenosos de la Formación Areniscas de Castellón. Este paleorelieve ha preservado numerosas estructuras susceptibles de ser empleadas para la captura y almacenamiento de CO2, lo que brinda la oportunidad de implementar una solución tecnológica a la descarbonización del cercano complejo industrial de Tarragona.
  • logoOpenAccessArticle
    Effects of global and climate change on the freshwater-seawater interface movement in a Mediterranean karst aquifer of Mallorca Island
    (Elsevier B.V., 2023-12-09) Gràcia, Francesc; Puigserver Cuerda, Diana; Giménez, Jordi; Granell, Àlvaro; Carmona Pérez, José Ma. (José María); Torrandell, Aina; Fornós, Joan J. (Joan Josep)
    Karst aquifers are globally prized freshwater sources, posing a significant preservation challenge. These aquifers typically exhibit dual or even triple porosities, encompassing matrix, fractures-fissures and conduits, rendering them highly responsive to variations in chemical characteristics and hydraulic head. In coastal regions, these aquifers often possess extensive subsurface conduit networks intricately linked to the rock matrix, facilitating groundwater discharge into the sea. Therefore, they display acute sensitivity to seawater intrusion, swiftly reacting to changes in precipitation and pumping regimes. This makes them exceptionally vulnerable to short-term meteorological fluctuations and long-term climate change. Their high heterogeneity leads to uneven penetration of the freshwater-seawater interface, causing rapid seawater intrusion inland over significant distances. The Mediterranean region, characterized by water deficit and water stress, faces strong impacts from climate change, featuring a warming atmospheric trend exceeding the global average, along with diminished rainfall exacerbating water scarcity. Increasing water demands for agriculture, urban development, and the growing tourism industry, because of global change, are worsening water stress. Our primary research objectives were analyzing the environmental consequences of global and climate change on seawater intrusion in Mediterranean coastal karst aquifers, with a focus on the role of the double-flow model, thus contributing to the understanding of the processes involved. To achieve this, we selected a study region on Mallorca Island in the western Mediterranean, where a karst aquifer system discharges into the sea. We employed various study methods, notably hydrochemical techniques and multi-isotopic analysis, encompassing the examination of 2H and 18O isotopes in water, 87Sr/86Sr ratio, Sr and B concentrations, and δ11B in water. A key finding is the rebound effect, wherein aquifers recontaminate due to solute molecular back-diffusion following cessation of extractions and the retreat of marine intrusion, providing insight into the impact of climate and global change on Mediterranean karst aquifers.
  • logoOpenAccessArticle
    A review of experimental investigations on salt precipitation during CO2 geological storage
    (Elsevier B.V., 2024-10-28) Sun, Xi; Liu, Kai; An, Senyou; Hellevang, Helge; Cao, Yongfa; Alcalde Sicilia, Judit; Travé i Herrero, Anna; Yuan, Guanghui; Deng, Chenguang; Gómez Rivas, Enrique
    Salt precipitation due to formation drying is a critical secondary alteration process that significantly impairs reservoir injectivity in the context of CO2 geological storage. In this work, salt precipitation during CO2 injection is reviewed primarily through various experimental studies. First, the experimental systems for salt precipitation studies, namely core-flooding, microfluidic-chip, static batch, and surface drying experimental systems, have been described to present their respective experimental procedures and merits, as well as corresponding applications. Subsequently, following the general description of the formation mechanisms of salt precipitation, the macro and micro salt distribution patterns at the reservoir and pore scales have been summarized. Finally, and most importantly, this study provides a comprehensive analysis of the controlling factors for salt precipitation, categorized into four different groups, according to the brine, rock, gas, and injection scenario aspects. Among all these factors, brine salinity, CO2 injection rate and initial reservoir properties are considered the most critical in determining the amount and distribution of precipitated salts and the degree of injectivity impairment. The effects of multi-scale reservoir heterogeneity and rock wettability on salt precipitation are attracting growing consideration, while the brine and gas composition studies are receiving less attention due to their relatively minor influences on reservoir alteration. Due to the limited specimen sizes, the ex-situ brine replenishment may be underestimated in core-flooding and microfluidic-chip experiments. This may result in a potentially significant underestimation of the volume of local salts and the potentially inaccurate prediction of the drying process during CO2 injection in many such experiments.
  • logoOpenAccessArticle
    Stratigraphy and diagenesis of the Thamama-b reservoir zone and its surrounding dense zones in Abu Dhabi oilfields and equivalent Oman outcrops
    (Wiley, 2024-09-23) Ehrenberg, S.; Neilson, J.; Gómez Rivas, Enrique; Oxtoby, N.; Jayachandran, I.; Qi, A.; Vahrenkamp, V.
    We review published studies characterizing the Thamama-B reservoir zone in the upper Kharaib Formation (late Barremian) in Abu Dhabi oilfields and at outcrops in Oman. Available data for oxygen and carbon isotope compositions, fluid inclusion measurements, cement abundance and formation water composition are interpreted in terms of a paragenetic model for the Thamama-B in field F in Abu Dhabi where the interval is deeply buried. The present synthesis provides a useful basis for understanding and predicting reservoir quality in static models and undrilled prospects, as well as for planning promising directions for further research. The goals of this study were to summarize the geologic setting and petrology of the Thamama-B reservoir and its surrounding dense zones, and to examine how sedimentology, stratigraphy and diagenesis have interacted to control porosity and permeability. Results that may have useful applications for similar microporous limestone reservoirs in general include:· the depositional environments and stratigraphy of the subject strata;· a model for how porosity variations result mainly from calcite cementation sourced from stylolites, with little dependence on lithofacies other than the localization of chemical compaction by depositional clay linked to sequence stratigraphy;· the use of solidity (rock thickness with porosity removed) as a check on porosity creation by burial dissolution;· observations linking high-permeability streaks with storm lag beds and fractures;· the concept of strata being gradually buried through a relatively static salinity-stratified water column;· integration of conventional and clumped stable-isotope data with petrologic observations to constrain the timing of porosity evolution.