Extracción, explotación, minería y proceso de tratamiento del yeso

Los últimos doscientos años de extracción y fabricación del yeso (efectuada inicialmente de forma rudimentaria y artesanal), han aportado una profunda evolución, transformando las primitivas formas de explotación hasta llegar a la minería actual.The last hundred years of extraction and production of the gypsum (initially in a rudimentary and artisanal way) have deeply evo-luted transforming the primitive ways of explotation until arriving to the present mining.Peer reviewe

The Upper Oligocene of Montgat (Catalan Coastal Ranges, Spain): New age constrains to the western Mediterranean Basin opening

The Oligocene deposits of Montgat are integrated in a small outcrop made up of Cenozoic and Mesozoic rocks located in the Garraf-Montnegre horst, close to the major Barcelona fault. The Oligocene of Montgat consists of detrital sediments of continental origin mainly deposited in alluvial fan environments; these deposits are folded and affected by thrusts and strike-slip faults. They can be divided in two lithostratigraphic units separated by a minor southwest-directed thrust: (i) the Turó de Montgat Unit composed of litharenites and lithorudites with high contents of quartz, feldspar, plutonic and limestone rock fragments; and (ii) the Pla de la Concòrdia Unit composed of calcilitharenites and calcilithorudites with high contents of dolosparite and dolomicrite rock fragments. The petrological composition of both units indicates that sediments were derived from the erosion of Triassic (Buntsandstein, Muschelkalk and Keuper facies), Jurassic and Lower Cretaceous rocks (Barremian to Aptian in age). Stratigraphic and petrological data suggest that these units correspond to two coalescent alluvial fans with a source area located northwestwards in the adjoining Collserola and Montnegre inner areas. Micromammal fossils (Archaeomys sp.) found in a mudstone layer of the Pla de la Concòrdia Unit assign a Chattian age (Late Oligocene) to the studied materials. Thus, the Montgat deposits are the youngest dated deposits affected by the contractional deformation that led to the development of the Catalan Intraplate Chain. Taking into account that the oldest syn-rift deposits in the Catalan Coastal Ranges are Aquitanian in age, this allows to precise that the change from a compressive to an extensional regime in this area took place during latest Oligocene-earliest Aquitanian times. This age indicates that the onset of crustal extension related to the opening of the western Mediterranean Basin started in southern France during latest Eocene-early Oligocene and propagated southwestward, affecting the Catalan Coastal Ranges and the northeastern part of the Valencia trough during the latest Chattian-earliest Aquitanian times

Stratigraphy and petrology of the Miocene Montjuïc delta (Barcelona, Spain)

The Neogene rift in the Catalan Coastal Ranges, which is located in the NE part of the Eastern Iberian Margin, corresponds to a system of grabens formed at the north-western edge of the Valencia Trough. In the central part of the Catalan Coastal Ranges are the Vallès - Penedès half-graben in the onshore and the Barcelona half-graben in the offshore, which are separated by the Garraf and the Collserola-Montnegre horsts. Montjuïc hill is a tilted block, which is located to the S of the Barcelona city, between the Collserola-Montnegre horst and the Barcelona half-graben . The Middle Miocene section of Montjuïc is constituted by an alternation of conglomerate, sandstone, mudstone and marlstone beds. The Montjuïc section was divided into four lithostratigraphic units from base to top: (1) The Morrot conglomerate and sandstone Unit, interpreted as delta plain deposits; (2) the Castell conglomerate, sandstone and mudstone Unit considered as proximal delta front deposits; (3) the Miramar marlstone Unit attributed to prodelta deposits; and (4) the Mirador conglomerate, sandstone and mudstone Unit interpreted as delta front deposits. As regards the foraminifera association, the Miocene of Montjuïc may be attributed to the N9-N10 zones of Blow, indicating a Serravallian age. The palaeobotanical record suggests that the climate during the deposition of the Miocene of Montjuïc was temperate-warm and humid. The sandstones and conglomerates are litharenites and lithorudites; they show variable amounts of matrix and are well cemented. The main framework components are quartz, rock fragments and K-feldspar. The Collserola mountain, where Palaeozoic materials crop out is the deduced source area. Montjuïc sandstones are characterized by an early silicic cementation consisting of K-feldspar overgrowths, quartz overgrowths, mesoquartz intergranular cement and a microquartz transformation of a former detrital matrix. A surface cementation is considered for these cements in the absence of compaction and the geological setting

Estratigrafía y petrología del subsuelo precuaternario del sector SW de la depresión de Barcelona (cadenas costeras catalanas, NE de Iberia)

Las numerosas obras de Ingeniería Civil que se han realizado en los últimos años en la depresión de Barcelona (ampliación del aeropuerto, ampliación del metro y AVE fundamentalmente) han permitido recabar mucha información sobre el subsuelo de esta área. En este trabajo se caracterizan las distintas unidades de subsuelo precuaternarias que aparecen en los numerosos sondeos realizados recientemente en la zona SW de la depresión de Barcelona. Se ha identificado un sustrato triásico formado por areniscas del Buntsandstein y dos unidades de edad Miocena, una basal de carácter continental y otra superior depositada en un ambiente marino. Todas estas unidades fueron fracturadas debido a una tectónica extensiva y, posteriormente, fueron fosilizadas en primer lugar por los sedimentos del Plioceno, que recubren la superficie de erosión messiniense, y finalmente, por el Cuaternario. El análisis de las distintas unidades permite obtener datos sobre la evolución paleogeográfica y tectónica de la depresión de Barcelona durante el Mioceno y el Plioceno.çCurrent building of civil Engineering infrastructures in the Barcelona plain and Llobregat delta (mainly metro and airport extension and high speed train) is providing new geological subsurface data to build better geologic models and understand the basin evolution. This work focuses on the pre-Quaternary units observed in cores. Based on petrographic analyses combined when it was possible with paleontological studies, we identified the lower Triassic Buntsandstein sandstone facies and Miocene continental and marine facies which appear compartmentalized due to extensive deformation. After this extensive episode, Pliocene and Quaternary sediments, which were deposited after the development of successive erosive surfaces, overlay the Triassic and Miocene units. The identification of these units enabled one to improve the interpretation of the tectonic and paleogeographic evolution of the Barcelona plai

Stratigraphy and petrology of the Miocene Montjuic delta: (Barcelona, Spain).

The Neogene rift in the Catalan Coastal Ranges, which is located in the NE part of the Eastern Iberian Margin, corresponds to a system of grabens formed at the nort h - we s t e rn edge of the Valencia Trough. In the central part of the Catalan Coastal Ranges are the Valls - Peneds half-graben in the onshore and the Barcelona half-graben in the offshore, which are separated by the Garraf and the Collserola-Montnegre horsts. Montjuc hill is a tilted block, which is located to the S of the Barcelona city, between the Collserola-Montn egre horst and the Barcelona half-graben . The Middle Miocene section of Montjuc is constituted by an alternation of conglomerate, sandstone, mudstone and marlstone beds. The Montjuc section was divided into four lithostratigraphic units from base to top: (1) The Morrot conglomerate and sandstone Unit, interpreted as delta plain deposits; (2) the Castell conglomerate, sandstone and mudstone Unit considered as proximal delta front deposits; (3) the Miramar marlstone Unit attribute

Estratigrafía y petrología del subsuelo precuaternario del sector SW de la depresión de Barcelona (Cadenas Costeras Catalanas, NE de Iberia)

Las numerosas obras de Ingeniería Civil que se han realizado en los últimos años en la depresión de Barcelona (ampliación del aeropuerto, ampliación del metro y AVE fundamentalmente) han permitido recabar mucha información sobre el subsuelo de esta área. En este trabajo se caracterizan las distintas unidades de subsuelo precuaternarias que aparecen en los numerosos sondeos realizados recientemente en la zona SW de la depresión de Barcelona. Se ha identificado un sustrato triásico formado por areniscas del Buntsandstein y dos unidades de edad Miocena, una basal de carácter continental y otra superior depositada en un ambiente marino. Todas estas unidades fueron fracturadas debido a una tectónica extensiva y, posteriormente, fueron fosilizadas en primer lugar por los sedimentos del Plioceno, que recubren la superficie de erosión messiniense, y finalmente, por el Cuaternario. El análisis de las distintas unidades permite obtener datos sobre la evolución paleogeográfica y tectónica de la depresión de Barcelona durante el Mioceno y el Plioceno.Peer ReviewedPostprint (published version

Mineralogical and thermal characterization of borate minerals from Rio Grande deposit, Uyuni (Bolivia)

Large volumes of borate resources exist in Bolivia, with the most important being the Rio Grande deposit, located close to the Salar of Uyuni. Here, borates occur in beds and lenses of variable thickness. A mineralogical and thermal characterization of borates from the Rio Grande was made using XRD, FTIR, SEM and DTA TG. The deposit is mainly composed of B2O3, CaO and Na2O, with minor contents of MgO and K2O. Some outcrops are constituted by pure ulexite aggregates (NaCaB5 O6(OH)6 5H2O) of fibrous morphology; in other cases, gypsum, calcite and halite also are present. The thermal decomposition of ulexite begins at 70 C and proceeds up to *550 C; this decomposition is attributed to dehydration and dehydroxylation processes in three steps: at 115, 150 300 and 300 550 C. The last mass loss of 1 5 % at 800 C is due to the removal of Cl2 from the decomposition of halite. DTA shows two endothermic events related to the removal of water; in the first, NaCaB5O6(OH)6 5H2O evolved from NaCaB5O6(OH)6 3H2O, at 108 116 C; in the second, NaCaB5O6(OH)6 is formed at 180 185 C and NaCaB5O9 (amorphous) is formed at 300 550 C. The exothermic peak (658 720 C) is related to the crystallization of NaCaB5O9. A small endothermic peak appears due to the halite melting. Later, another endothermic event (821 877 C) appears, which is related to the decomposition of NaCaB5O9 into a crystalline phase of CaB2O4 and amorphous NaB3O5. The XRD pattern evidences that, at 1050 C, CaB2O4 still remains in the crystalline state

Permian-Triassic red-stained albitized profiles in the granitic basement of the NE Spain: evidence for deep alteration related to the Triassic Palaeosurface

Extensive areas of the Variscan granitic basement in NE Spain display profiles of red-stained albitized facies characterized by albitization of Ca-plagioclase, chloritization of biotite and microclinization of orthoclase, along with the alteration of igneous quartz to secondary CL-dark quartz. These profiles have a geopetal structure beneath the Triassic unconformity, with a very intense and pervasive alteration in the upper part that progressively decreases with depth to 150-200 m where the alteration is restricted to the walls of fractures. The red albitized facies contains secondary maghemite and hematite that indicate oxidizing conditions. Dating of microclinized orthoclase and secondary monazite that have formed in the red-stained albitized facies yielded K-Ar and U-Th-Pbtotal ages of 240 and 250 Ma, respectively, suggesting that the alteration developed during the Permian-Triassic period. The geopetal disposition of the red albitized profile with respect to the Triassic unconformity, its large regional extent, and the fracture-controlled alteration in the lower part of the profile indicate groundwater interaction. The δ18O values of albitized plagioclase (+ 11¿), microclinized orthoclase (+ 13¿), and secondary CL-dark quartz (+ 12¿) suggest that the alteration temperature was about 55 °C. This 'low' temperature suggests that the alteration occurred during interaction of the granitic rocks with Na-rich fluids below a surficial weathering mantle on the Permian-Triassic palaeosurface. The latter is possibly related to Triassic evaporitic environments in long-lasting, stable landscapes in which Na-rich solutions infiltrated deep regional groundwaters

Obtención de vidrio a partir de residuos de la minería del estaño en Bolivia

Manufacturing of glass from tin mining tailings in Bolivia Tailings from mining activities in Bolivia represent an environmental problem. In the vicinity of the tin mines of Llallagua,Potosí department, there are large dumps and tailings. We present a study of the use of these wastes as raw materials for the manufacture of glass. This procedure aims to contribute to environmental remediation of mining areas through the vitrification, a process which offers an alternative for stabilization of hazardous waste. In addition, the marketing of the obtained product would provide an additional income to the mining areas. For this study three samples of mining waste, with grain size between sand and silt, were used. The chemical composition of these raw materials, determined by X-ray fluorescence, is granitic, with high contents of heavy metals. On the basis of its composition, glass were made from silica glass by adding CaCO3 and Na2CO3. The thermal cycle has been determined from TDA. Tg values of glass range from 626º to 709 °C. Leaching tests of the obtained glasses confirm their capacity to retain heavy metals

Medicaments dispensats als pacients amb síndrome gripal en l’àmbit de la Xarxa de farmàcies sentinella de Catalunya durant la temporada de grip 2018-2019

Grip; Vigilància sindròmica; Farmàcies sentinellaGripe; Vigilancia sindrómica; Farmacias centinelaInfluenza; Syndromic surveillance; Sentinel pharmaciesObjectius. Analitzar les dades sobre la mediació dispensada i prescrita als pacients amb síndrome gripal en l’àmbit de la Xarxa de farmàcies sentinella de Catalunya durant la temporada de grip 2018-2019. Mètodes. Es van analitzar les dades recollides dels casos de síndrome gripal declarats per les 60 farmàcies sentinella de Catalunya en el període de l’1 d’octubre de 2018 al 20 de maig de 2019. Es va utilitzar el programa IBM-SPSS per analitzar les característiques dels casos de síndrome gripal declarats per les farmàcies sentinella i per determinar els percentatges de medicació dispensada i de medicació prescrita en diferents grups de població. Resultats. Es van declarar 1.000 casos de síndrome gripal en el període d’estudi. El 48% del casos declarats van ser homes i el 52% van ser dones. El 67,4% dels casos declarats es van detectar a la farmàcia comunitària, i el 13,3% dels casos es van derivar a equips d’atenció primària. Les oficines de farmàcia van dispensar medicaments que contenien, únicament, paracetamol, ibuprofèn, àcid acetilsalicílic, antihistamínics o antitussígens al 77% dels pacients, i van dispensar alguna medicació al 95,3% dels pacients. Conclusions. El sistema d’informació sindròmica de grip basat en la Xarxa de farmàcies sentinella ha permès obtenir informació sobre la morbiditat per grip no assistida en centres de salut i sobre la medicació dispensada als pacients amb síndrome gripal a Catalunya.Analizar los datos sobre la mediación dispensada y prescrita a los pacientes con síndrome gripal en el ámbito de la Red de farmacias centinela de Cataluña durante la temporada de gripe 2018-2019. Métodos. Se analizaron los datos recogidos de los casos de síndrome gripal declarados por las 60 farmacias centinela de Cataluña en el periodo del 1 de octubre de 2018 al 20 de mayo de 2019. Se utilizó el programa IBM-SPSS para analizar las características de los casos de síndrome gripal declarados por las farmacias centinela y para determinar los porcentajes de medicación dispensada y de medicación prescrita en diferentes grupos de población. Resultados. Se declararon 1.000 casos de síndrome gripal en el periodo de estudio. El 48% de los casos declarados fueron hombres y el 52% fueron mujeres. El 67,4% de los casos declarados se detectaron en la farmacia comunitaria, y el 13,3% de los casos se derivaron a equipos de atención primaria. Las oficinas de farmacia dispensaron medicamentos que contenían, únicamente, paracetamol, ibuprofeno, ácido acetilsalicílico, antihistamínicos o antitusígenos al 77% de los pacientes, y dispensaron alguna medicación al 95,3% de los pacientes. Conclusiones. El sistema de información sindrómica de gripe basado en la Red de farmacias centinela ha permitido obtener información sobre la morbilidad por gripe no asistida en centros de salud y sobre la medicación dispensada a los pacientes con síndrome gripal en Cataluña.Objectives. To analyse the data on medication dispensed and prescribed to patients with influenza-like syndrome obtained from the Catalan sentinel pharmacy network during the 2018−2019 influenza season. Methods. Data collected from cases of influenza-like syndrome reported by the 60 sentinel pharmacies of Catalonia during the period from October 1, 2018 to May 20, 2019 were analysed. The IBM-SPSS programme was used to analyse the characteristics of cases reported and to determine the percentages of medication dispensed and prescribed in different population groups. Results. A total of 1000 cases of influenza-like syndrome were reported during the period of study. A total of 48% of cases reported were men and 52% were women. A total of 67.4% of reported cases were detected in the community pharmacy, and 13.3% of cases were referred to primary care teams. The pharmacies dispensed medications including only paracetamol, ibuprofen, acetyl salicylic acid, antihistamines or antitussives to 77% of the patients, and dispensed a medication to 95.3% of the patients. Conclusions. The influenza syndromic surveillance system based on the sentinel pharmacy network has made it possible to obtain information on influenza morbidity not assisted in health centres and on the medications dispensed to patients with influenza-like syndrome