Search results for "Vulcano"
showing 10 items of 469 documents
Total CO2 output from Vulcano island (Aeolian Islands, Italy)
2012
Total CO2 output from fumaroles, soil gas, bubbling gas discharges and water dissolved gases discharged from the island, was estimated for Vulcano island, Italy. The CO2 emission from fumaroles from the La Fossa summit crater was estimated from the SO2 crater output, while CO2 discharged through diffuse soil emission was quantified on the basis of 730 measurements of CO2 fluxes from the soil of the island, performed by using the accumulation chamber method. The results indicate an overall output of ≅500 t day 1 of CO2 from the island. The main contribution to the total CO2 output comes from the summit area of the La Fossa cone (453 t day 1), with 362 t day 1 from crater fumaroles and 91 t d…
Degassing at the Volcanic/Geothermal System of Kos (Greece): Geochemical Characterization of the Released Gases and CO2 Output Estimation
2019
Forty-five gas samples have been collected from natural gas manifestations at the island of Kos—the majority of which are found underwater along the southern coast of the island. On land, two anomalous degassing areas have been recognized. These areas are mainly characterized by the lack of vegetation and after long dry periods by the presence of sulfate salt efflorescence. Carbon dioxide is the prevailing gas species (ranging from 88 to 99%), while minor amounts of N2 (up to 7.5%) and CH4 (up to 2.1%) are also present. Significant contents of H2 (up to 0.2%) and H2S (up to 0.3%) are found in the on-land manifestations. Only one of the underwater manifestations is generally rich in N2 (up t…
Shrinkage Bubbles: The C–O–H–S Magmatic Fluid System at San Cristóbal Volcano
2018
New analytical results for the composition of shrinkage bubbles (09-70 vol. %) in olivine-hosted (Fo <80%) primary melt inclusions (MIs) have been incorporated into a novel geochemical model for San Cristó bal volcano, Nicaragua. The vapour, liquid, and mineral components found inside shrinkage bubbles may represent relics of early C-O-H-S fluids exsolved from a magmatichydrothermal system. This conclusion is supported by high-resolution Raman microspectroscopy revealing: (1) gaseous CO2 (d=0·17-0·31 g/cm3 in 31 samples) coexisting with liquid H2O (in seven samples) at ambient temperature (<22°C) inside the shrinkage bubbles of naturally quenched inclusions; (2) several mineral phases (i.e.…
Carbonate deposition and diagenesis in evaporitic environments: The evaporative and sulphur-bearing limestones during the settlement of the Messinian…
2015
The depositional and diagenetic processes involved in the formation of carbonates in the evaporitic environment of the Messinian Salinity Crisis are investigated in Southern Italy (Sicily and Calabria). Strong differences are observed between the studied sections that reflect specific depositional and diagenetic evolution in the interconnected sub-basins resulting from the syn-sedimentary tectonic fragmentation of the Central Sicilian and Calabrian domains. These carbonates formed diachronously in restricted perched sub-basins between the Tripoli Formation and the hypersaline settings of the MSC. The Calcare di Base (CdB) that can be interbedded with gypsum layers occurs rhythmically at the…
Fluid geochemistry in a low-enthalpy geothermal field along a sector of southern Apennines chain (Italy)
2020
Abstract The chemical and isotopic features of the fluids (water and gases) in the Lucane thermal area (southern Italy) have been investigated in order to verify their origin, water temperature in the geothermal reservoir, and to recognize the main natural processes concerning the water composition during ascent towards the surface. The Lucane geothermal system is placed in the southern sector of the Apennines chains, a seismically active area, close to the southern base of the Mt. Alpi carbonate massif. Along the study area, two main sets of high-angle faults form an almost orthogonal fault system that, as suggested by local structural geology, acts as a preferential pathway for uprising d…
Geochemical characteristics of waters in mineralised area of Peloritani Mountains (Sicily, Italy)
2009
Abstract This paper presents the results of a study on the geochemistry of waters circulating in the mineralised area of the south-eastern sector of Mt. Peloritani (north-eastern Sicily, Italy), aimed at basic understanding of the geochemical processes influencing their chemical composition. Chemico-physical parameters and data on 26 major and minor chemical elements are reported for 103 water samples. Water chemistry is mainly dominated by dissolution of carbonates and hydrolysis of aluminosilicate minerals. Total dissolved salts (TDS) range from 80 to 1398 mg/L. All the waters exhibit E H characteristic of an oxygenated environment. Excluding two samples, which show very high H + activity…
Sicilian bottled natural waters: Major and trace inorganic components
2013
Sixteen bottled waters of various Sicilian brands, 11 natural mineral waters and five normal drinking waters, were analyzed for major and trace inorganic components by ion chromatography (IC) and inductively coupled plasma-mass spectrometry (ICP-MS), respectively. The bottled waters represent a variety of water types with significantly different compositions in terms of salinity, major components and trace elements. Chemically, they range from Ca–HCO3 and Ca–SO4 to Na–HCO3 types. Total dissolved solids ranges from 54 to 433 mg/L, total hardness from 25 to 238 mg/L CaCO3, and measured Na content from 5.7 to 57 mg/L. According to total dissolved ions, all the bottled waters were classified as…
Environmental RNA outperforms eDNA metabarcoding in assessing impact of marine pollution: A chromium-spiked mesocosm test
2022
Environmental (e)DNA metabarcoding holds great promise for biomonitoring and ecotoxicological applications. However, few studies have compared the performance of eDNA versus eRNA metabarcoding in assessing organismal response to marine pollution, in experimental conditions. Here, we performed a chromium (Cr)-spiked mesocosm experimental test on benthic foraminiferal community to investigate the effects on species diversity by analysing both eDNA and eRNA metabarcoding data across different Cr concentrations in the sediment. Foraminiferal diversity in the eRNA data showed a significant negative correlation with the Cr concentration in the sediment, while a positive response was observed in t…
Estudio Hidrogeoquimico De Las Áreas Termales Del Complejo Volcánico Copahue-Caviahue
2016
Hydrogeochemical study on Thermal areas of the Copahue-Caviahue Volcanic Complex The hydrothermal system hosted in the Copahue- Caviahue Volcanic Complex consists of different geothermal areas around the Copahue volcano, whose last eruptive cycle started on December 22 of 2012. This work presents new data from the samplings of November 2012 and march 2013 in Las Maquinas, Las Maquinitas, villa de Copahue and Chancho-Có areas. These acid-sulfate and steam heated waters, presented changes in their SO4-2 concentrations, especially in Las Maquinas and Las Maquinitas areas. Meanwhile, SO4-2/Cl- ratios presented a strong decrease in the samples from November 2012, regarding the samples from 2013.…
Fluorine adsorption by volcanic soils at Mt. Etna, Italy
2012
Abstract Fluorine adsorption experiments were performed on 28 samples of the first 5 cm of topsoil collected on the flanks of Mt. Etna. The soil samples were equilibrated with F-rich rainwater (3.25 mg/L) at a soil/water weight ratio of 1/25. Aliquots of the supernatant were collected after 1, 7, 72, 720 and 5640 h and analysed for F content. The soil samples could be subdivided into three groups based on their F-adsorption behaviours after 1 h and at the end of the experiment: (1) negative adsorption (F released from the soil to the solution) after 1 h and negative or moderately positive adsorption at the end, (2) from negative after 1 h to strongly positive adsorption at the end, and (3) …