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The Ofanto River drains volcanic rocks from the Monte Vulture, lacustrine–fluviolacustrine deposits associated with the same volcano and sedimentary deposits of the Southern Apennines and the Bradanic foredeep sequences. Comparing the modal composition of river sands and the outcrop area of different lithologies in the different sub-basins, an over-concentration of the volcaniclastic fraction, mainly represented by loose crystals of clinopyroxene, garnet and amphibole, is shown. This has been related to the preferential erosion of pyroclastic deposits, characterized by high production of sand-sized loose minerals, together with the carbonate lability and the low sand-sized detritus production from claystones and marls. The occurrence of volcaniclastic components upstream of Monte Vulture can be explained as a contribution from the lacustrine–fluviolacustrine deposits cropping out in the upstream sector or from pyroclastic fall deposits of Monte Vulture and/or Campanian volcanoes. This research shows that the volcanic record in the fluvial sands of the Ofanto River comes from weathering and sorting processes of volcaniclastic deposits rather than of the lavas building the main edifice. Therefore, caution must be taken during palaeoenvironmental and palaeoclimatic reconstructions when relating the type and abundance of the volcanic component in sediments to the weathering stage and evolutionary history of the volcano.

A multidisciplinary approach adopting new geological, hydro-geochemical and isotopic data has been used to assess the genesis of hot and cold waters of the Galatro and Antonimina thermal systems. In these systems, waters come from two different hydrogeological circuits, which are chiefly hosted in the Palaeozoic crystallino-methamorphic rocks of the Aspromonte Unit and the overlying Oligocene-Pleistocene sedimentary sequences. In particular, the Galatro thermal water shows Na–SO 4 composition, pH value of 7.85 ± 0.13, outlet temperature of 36.4 ± 1.8 °C, variable Eh (−266 to −42 mV) and total dissolved solids of 1,067 ± 149 mg L −1 . Conversely, the Antonimina thermal water shows Na-SO 4 (Cl) composition, total dissolved solid of 10,369 ± 1,613 mg L −1 , pH value of 7.62 ± 0.17, outlet temperature of 35 ± 0.12 °C and Eh from 25.4 to 49.2 mV. Geological and hydrogeochemical data suggest that the meteoric waters infiltrating along the Aspromonte Chain at different elevations (650 and 230 m a.s.l. for Galatro and Antonimina respectively), recharge the aquifers acquiring heat from rocks through conductive transfer reaching reservoir temperatures between 69 ± 15 °C and 101 °C for Galatro and 60 ± 19 °C for Antonimina reservoirs, as indicated by the solubility of chalcedony and quartz and Na/K geothermometers. Subsequently, the waters leaving the deep reservoirs discharge at the surface at 36.4 ± 1.8 °C and 35 ± 0.12 °C after a relatively fast upflow and limited cooling. Assuming a normal geothermal gradient (33 °C km −1 ), results allowed to locate the warm deeper reservoirs of Galatro and Antonimina at depths between 1.5 and 2.5 km and 1.5 km respectively.

The geochemical characteristics of the Calabrian thermal waters have already been investigated in several studies which adopted a sort of ‘‘regional’’ approach. On the other hand, the recent works by Vespasiano et al., 2014 and Apollaro et al. 2019 were focused to specific thermal sites with the aim to investigate the geochemistry and to reconstruct the local geothermal conceptual model. In this study, was adopted the same ‘‘local’’ approach to investigate the geochemistry of the warm and cold-water discharges from the Cotronei and Caccuri thermal area. Bruciarello, Cotronei (Ponte Coniglio) and Repole thermal areas fall in the proximity of the western side of the Crotone Basin made up of terrains structured between the middle Miocene and Holocene, transgressive on the crystalline basement belonging to the Sila massif. The Basin, located on the Ionian side of the PCO (Peloritan Calabrian Orogen), was interpreted like a forearc basin in the inner portion of the Calabrian accretion wedge.Geochemical and hydrogeological data allow to identify the presence of (i) a deep primary geothermal endmember hosted into the crystalline basement (Cotronei system), and (ii) secondary shallow systems developed in the Miocene sedimentary successions (Bruciarello and Repole). All thermal waters have shown different composition: Na(Ca)-Cl composition for Ponte Coniglio-Cotronei (EC 3.57 ± 0.22 mS/cm), Na(Ca)-Cl(SO4) composition for Bruciarello (EC 8.17 ± 0.76 mS/cm) and Na-SO4(Cl) composition for Repole (EC 4.15 mS/cm). The water-rock interaction between primary fluids and evaporitic succession leads to the formation of the secondary Bruciarello and Repole systems. In these sites, the thermal endmember, hosted in the crystalline basement, infiltrates within Miocene evaporitic successions and undergone important compositional changes due to Anhydrite (or gypsum) and sodium Al-silicates dissolution (e.g. Albite) followed by precipitation of phases such as calcite and clay minerals (e.g. Caolinite).The silica geothermometers indicated temperatures of 55 ± 2 °C for the endmember and slightly lower temperatures for the remaining two systems. Furthermore, δ18O and δ2H values highlight a meteoric origin for all thermal systems and provide infiltration altitude of about 1650 – 1850 m a.s.l. that agree with the Sila plateau heights.Assuming a geothermal gradient of about 33°C/km, a temperature for the deep thermal reservoir of ⁓55 °C and an average atmospheric temperature of 6°C in the recharge area (Sila plateau), it can be assumed that the meteoric waters descend to depths of 1500 m, where the thermal aquifer is located. This data would confirm the location of the primary geothermal reservoir within the crystalline basement.Apollaro C., Tripodi V., Vespasiano G., De Rosa R., Dotsika E., Fuoco I., Critelli S., Muto F. 2019. Chemical, isotopic and geotectonic relations of the warm and cold waters of the Galatro and Antonimina thermal areas, southern Calabria, Italy. Marine and Petroleum Geology. 109, 469–483. https://doi.org/10.1016/j.marpetgeo.2019.06.020Vespasiano G., Apollaro C., Muto F., Dotsika E., De Rosa R., Marini L. 2014 - Chemical and isotopic characteristics of the warm and cold waters of the Luigiane Spa near Guardia Piemontese (Calabria, Italy) in a complex faulted geological framework. Applied Geochemistry, 41, 73-88.

A multi-disciplinary study, integrating volcanological field observations, petrography, whole rock geochemistry and textural and compositional analyses on plagioclase crystals has been carried out on the products of Monte Luccia, Spiaggia Lunga, and Quadrara eruptions, occurred between 48 and 21 kyrs on the island of Vulcano. These products are all characterized by welded scoria blankets, and their eruptions have been generally related to the formation and/or re-activation of ring faults bordering the “Il Piano” caldera. The aim of the work is to reconstruct the pre- and syn-eruptive dynamics acting within their magma plumbing systems and the related link with the phases of caldera collapse. At the bottom of the stratigraphic sequences, the presence of base surge deposits suggests that all the eruptions started with a phreatomagmatic phase fed by a shallow reservoir. Textural and microanalytical study of plagioclase crystals of Spiaggia Lunga eruption revealed that the phreatomagmatic event activated the ascent of a volatile-rich, basaltic magma residing at 5–11 km of depth. This basaltic magma mixed with the resident shallow one, and was poured out during the course of the eruption producing a sustained lava-fountaining phase. The subsequent caldera collapse, identified by a layer of chaotic breccia interbedded in the scoriae deposit, has been linked to the partial emptying of the shallow magma reservoir. In contrast to what observed for recent eruptive events at Vulcano, the onset of the magmatic phase would be attributed to a self-activation due to volcano-tectonic events, and not to a pressurization of the plumbing system related to the ascent of deep magma batches. As concerns the Mt. Luccia deposits, bordering the eastern rim of the “Il Piano” caldera, the absence of plagioclase in the mineralogical assemblage suggests the eruption of a deeper magma (>11 km b.s.l.), rapidly ascending through the re-activated ring faults of “Il Piano” caldera. At Quadrara eruption, the occurrence of a layer of white biotite-bearing latitic pumices overlying the basal phreatomagmatic deposits suggests the involvement a shallow, isolated reservoir where the increase of volatile pressure allowed the crystallization of hydrous phases. A deeper shoshonitic magma was involved later in the eruption, forming the welded scoria level at the top of the sequence.

An integrated petrological and geochemical study on plagioclase crystals erupted at Vulcano Island (Aeolian Islands, Southern Italy) over the past 1000 years allowed us to draw a detailed model of the internal structure of the volcanic system, in which modes of magma interaction and timescales of storage at crustal depth are shown. The integration of compositional, textural and temporal record preserved in plagioclase crystals provides evidence for an articulated plumbing system constituted by several reservoirs connected at the crust-mantle boundary. Here, a basaltic-shoshonitic magma resides and is thought to feed the shallow magma reservoir of both La Fossa and Vulcanello centers, finally triggering eruptions throughout injections from depth. Textural and micro-compositional data on plagioclase crystals suggest the presence of three main magma levels located between ca. 17 and 2 km of depth beneath La Fossa Cone, which were intermittently reactivated over the whole period of activity considered. Plagioclase textures and compositional zoning indicate that the shallow (

This work focuses on the textural characterization of modern sand supplied from a volcanic island in the Aeolian Archipelago, with particular attention given to the factors that control grain rounding. Twelve beach sands were collected from hightide berms spaced along Lipari’s accessible coastal perimeter. Point-count data were collected using a petrographic microscope with an automated stepper stage. Changes in grain roundness were assessed to evaluate grain resistance to transport(currents and wave abrasion). A numerical value was assigned to very angular (1), angular (2), sub-angular (3), sub-rounded (4), rounded (5) and well-rounded (6) categories. Analyzed particles are monocrystalline grains of plagioclase (Plag) and pyroxene (Py) and volcanic lithic fragments of Lvl (volcanic lithic with lathwork texture), Lvmi (volcanic lithic with microlitic texture), Lvv (volcanic lithic with vitric texture) and Lvf (volcanic lithic with felsitic texture). The most common roundness category among all the grains from the sampled coastal stretches of Lipari island is 3 (sub-angular, 36,1%), immediately followed by 2 (angular, 28,5%), 4 (sub-rounded, 20,0%), 1 (very angular, 10,1%), 5 (rounded, 4,2%) and lower occurrence of 6 (well rounded, 1,1%). We have also determined that some grain types tend to round more quickly in beach environments, such as plagioclase among the monocrystalline grains and Lvmi among the lithic grains population. Lipari’s beach sands are all better rounded on the eastern side which is the more protected part of the island. Alternatively, the sand grains on the east side of the island have alonger residence time on the beach.

Identifying differences of vanadium concentrations in soils is essential to individuate pollution sources and potential risks to humans and the environment. Marked differences in the geochemical composition of the rocks, which form the parent materials of soils, and variations in the intensity of soil-forming processes can result in wide ranges of concentrations of vanadium in soils, even in those unaffected by contamination. Conversely, the anthropogenic input can give rise to contamination in urban soil. The main aim of this study was to analyse the concentrations of vanadium in a southern Italy area, in both rural and urban soils, in order to determine different geochemical sources. In the study area, 149 topsoil samples were collected (0.10 m) and analysed for vanadium and other elements by ICP-MS. Statistical and geostatistical methods were used to identify the main factors influencing the different sources of vanadium in urban and peri-urban soils and to map the concentrations of vanadium. The concentrations of V were higher in the rural soils where were related to the ophiolite-bearing units outcroppings, which influenced importantly the distribution of vanadium, rather than in the urban soil, where were lowly affected by anthropogenic pollution due, predominantly, to circulating vehicle fuels. In urban area the mean concentration of vanadium amounted below the critical threshold value imposed by Italian Decree 152/2006.

Geochemical, geological, and hydrological data suggest, for the Cotronei-Caccuri thermal area (Northern Calabria – Southern Italy), the presence of a deep primary geothermal aquifer hosted in the crystalline basement (at Ponte Coniglio) and two secondary aquifers (at Bruciarello and Repole) developed in the Miocene sedimentary succession. Despite the spatial proximity of the three thermal sites, the waters have different compositions: Na(Ca)-Cl for Ponte Coniglio-Cotronei, Na(Ca)-Cl(SO4) for Bruciarello and Na-SO4(Cl) for Repole. The composition of the Cotronei-Ponte Coniglio end-member was reconstructed based on conservative constituents and resulted in a Cl concentration of about 1700 mg kg−1. The thermal waters of Bruciarello and Repole are derived from this primary fluid. Geothermometric calculations support a possible dilution affecting the waters studied to different degrees. For the pure (undiluted) thermal end-member, hosted in the primary granitic aquifer, comparable temperature estimations are provided by cationic geothermometers (67 ± 4 °C) and geothermometric simulations (65 ± 4 °C). However, Bruciarello and Repole waters are in equilibrium with anhydrite and fluorite at a temperature (68.5 ± 4 °C) very similar to that obtained for the granitic aquifer suggesting slight cooling during the travel from the primary granitic aquifer and fast equilibration with anhydrite and fluorite favoured by the rapid dissolution kinetics of these solid phases. From the isotopic point of view, the secondary aquifers have δ34SS(6+) values (+23.01‰ and +22.77‰ ± 0.23‰) comparable with those of the Messinian gypsum (average of +21.8‰). The thermal waters of Cotronei, on the other hand, show enriched δ34SS(6+) values (+38.60‰ ± 0.78‰) due to bacterial reduction of sulfate probably also derived from by Messinian evaporates. Furthermore, the δ18O and δ2H values indicate a meteoric origin for all three thermal sites with an average infiltration altitude of about 1650 – 1850 m asl, which agree with the Sila plateau elevations. Based on the results obtained in this work, assuming a geothermal gradient of about 33 °C/km, a temperature of the deep thermal reservoir of about 65 °C and an average predicted atmospheric temperature of 6 °C in the recharge area (Sila plateau), it follows that the meteoric waters descend to depths of ∼1800 m, where the thermal aquifer of interest is presumably located. This depth is consistent with the location of the primary geothermal reservoir within the crystalline basement. The reconstruction of this conceptual model has been made possible thanks to adopting a "local" approach integrating previously existing and new geological, hydrogeological, and geochemical data. Furthermore, this study has allowed us to identify the presence of an important regional geothermal aquifer hosted in the crystalline basement that, in addition to the carbonate and Upper Triassic evaporite reservoirs (well characterized in previous works), make the Calabria region of high geothermal interest.

Manganese ores, especially the oxyhydroxides in their different forms, are the dominant Mn-bearing minerals that occur in marine and terrestrial environments, where they are typically found as poorly crystalline and intermixed phases. Mn oxyhydroxides have a huge range of industrial applications and are able to exert a strong control on the mobility of trace metals. This paper reports the results of a detailed study on the Mn oxyhydroxides occurring in the manganiferous deposit outcropping in the Messinian sediments from Serra D'Aiello (Southern Italy). Nine Mn samples were characterized in detail using X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), thermogravimetry (TG), transmission electron microscopy combined with energy dispersive spectrometry (TEM/EDS), and X-ray fluorescence (XRF). The results indicated that the Mn deposit included the oxyhydroxide mineral species birnessite, todorokite, and ranci&egrave, ite. The size, morphology, and chemical composition of Mn oxyhydroxide samples were investigated in order to define their impact on the environment and human health. Todorokite displayed asbestiform shapes and could disperse fibers of breathable size in the air. Furthermore, since in-depth characterization of minerals within Mn deposits may be the first step toward understanding the genetic processes of manganese deposits, hypotheses about the genesis of the Mn oxyhydroxide deposits were discussed.

Rare Earth Elements (REE; lanthanides and yttrium) are elements with high economic interest because they are critical elements for modern technologies. This study mainly focuses on the geochemical behavior of REE in hyperacid sulphate brines in volcanic-hydrothermal systems, where the precipitation of sulphate minerals occurs. Kawah Ijen lake, a hyperacid brine hosted in the Ijen caldera (Indonesia), was used as natural laboratory. Sigma REE concentration in the lake water is high, ranging from 5.86 to 6.52 mg kg(-1). The REE pattern of lake waters normalized to the average local volcanic rock is flat, suggesting isochemical dissolution. Minerals spontaneously precipitated in laboratory at 25 degrees C from water samples of Kawah Ijen were identified by XRD as gypsum. Microprobe analyses and the chemical composition of major constituents allow to identify possible other minerals precipitated: jarosite, Al-sulphate and Sr, Ba-sulphate. Sigma REE concentration in minerals precipitated (mainly gypsum) range from 59.53 to 78.64 mg kg(-1). The REE patterns of minerals precipitated normalized to the average local magmatic rock show enrichment in LREE. The REE distribution coefficient (KD), obtained from a ratio of its concentration in the minerals precipitated (mainly gypsum) and the lake water, shows higher values for LREE than HREE. KD-LREE/KD-HREE increases in the studied samples when the concentrations of BaO, MgO, Fe2O3, Al2O3, Na2O and the sum of total oxides (except SO3 and CaO) decrease in the solid phase. The presence of secondary minerals different than gypsum can be the cause of the distribution coefficient variations. High concentrations of REE in Kawah Ijen volcanic lake have to enhance the interest on these environments as possible REE reservoir, stimulating future investigations. The comparison of the KD calculated for REE after mineral precipitation (mainly gypsum) from Kawah Ijen and Poas hyperacid volcanic lakes allow to generalize that the gypsum precipitation removes the LREE from water.

Over the last few years, the risk to human health related to asbestos fiber exposure has been widely demonstrated by many studies. Serpentinites are the main rocks associated with naturally occurring asbestos (NOA). In order to investigate the presence of NOA, a mineralogical study was conducted on eleven serpentinite samples collected nearby the village of Episcopia (Lucania, Southern Italy). Various analytical techniques such as X-ray powder diffraction (XRPD), scanning electron microscopy combined with energy dispersive spectrometry (SEM-EDS) and derivative thermogravimetry (DTG) were used to determine the occurrence of asbestos minerals and to make morphological observations. Results pointed out that all of the samples contain asbestos minerals (e.g., tremolite, actinolite and chrysotile). Moreover, it was observed that both natural processes and human activity may disturb NOA-bearing outcrops and provoke the formation of potentially inhalable airborne dust causing the release of asbestos fibers into the environment, thereby increasing the risk to human health. For this reason, our study aims to highlight the requirement of a natural asbestos survey and periodic update in the area.

We analysed a widespread, massive ash unit outcropping on the island of Lipari, which belongs to the Intermediate Brown Tuffs (IBT) succession of the Aeolian Islands, Italy. The use of a multidisciplinary approach that integrates textural, petrological and pedological methods, allows us to discriminate between syn-eruptive and post-depositional features. The deposits are dominated by uncrystallised blocky glass fragments of homogeneous shoshonitic composition, confirming a provenance from hydromagmatic eruptions on the island of Vulcano. Many glass fragments are surrounded by a coating separated by a thin void of syn-eruptive origin due to alteration by aggressive acid gases in the eruptive cloud. The lack of this coating in the northern part of Lipari can be explained as a progressive dispersion of the gases far from the vent and/or to post-depositional processes. The degree of soil development significantly increases from south (soil profiles P1 and P2 at Valle Muria) to north (P3 and P4, at Madoro and Chiesa Vecchia sites, respectively) as a response to a decrease in slope steepness, which has brought about a progressive deepening of the pedogenetic front on gentler landforms and conversely its rejuvenation on steep slopes. The relatively poor to moderate degree of pedogenic evolution of the studied IBT unit is consistent with its emplacement during part of the last glacial period.

Volcanic activity represents one of the main factors controlling the geological evolution of Mars, whose morphology has remarkable counterparts on Earth. Studies on the Martian surface revealed the widespread occurrences of newly formed minerals originated by the hydrothermal alteration of volcanic rocks. In this work, we carried out a series of experiments to test the reactions occurring during the hydrothermal alteration of basaltic ash from Etna (Italy) as a possible similar reaction fully grown on the Martian rock. The volcanic ash used for the hydrothermal alteration experiments was collected during the eruption of Etna in 2001, and its composition shares similarities with Martian bedrocks. Ash was altered under hydrothermal conditions at initial pH 5 at two temperatures (150 and 200 &deg, C) and reaction times of 5, 10, and 31 days. After a number of runs, we attained analcime NaAlSi2O6&middot, H2O. Our findings are in line with the hypothesis that zeolite on Mars probably originated from a low-temperature hydrothermal environment. The conclusions accord with the assumption that the analcime crystals recognized on Mars formed under the same conditions as those of our experimental setups.

A preliminary geochemical characterization of Cerchiara thermal waters was carried out. Waters discharging at the Cerchiara springs come from a deep circuit, which is chiefly hosted in the limestones, dolomitic limestones and evaporites of the Pollino Unit. Triangular plots of major dissolved cations and anions show that the Cerchiara thermal waters have a mixed Na(Ca)-Cl(HCO3-SO4) composition deriving from extended interaction with carbonate-evaporite rocks. Dissolved sulfate has an Upper Triassic derivation as indicated by sulfur isotopes provided that the effects of bacterial sulfate reduction are properly taken into account. Meteoric waters, infiltrating in the Pollino massif at elevations close to 1800 m asl, recharge the deep aquifer deepening along one or more fault systems, as suggested by local structural geology. They acquire heat from reservoir rocks through conductive transfer during their prolonged circulation into the deep aquifer at temperatures close to 40°C and PCO2 of ~2.5 bar. The thermal deep aquifer acts as a sort of well-mixed reservoir, whose fluids are completely mixed with the fluids entering it. The water leaving the deep reservoir discharges at the surface at 30 °C after a relatively fast upflow and limited cooling. The upward part of the hydrogeological circuit is controlled by local low and high-angle fault systems as well as by the tectonic window of Cerchiara di Calabria, where the Cerchiara Formation crops out.

Literature data with new geological, hydrogeological and geochemical investigations have been used to model the thermal spring waters of Caronte. Waters come from a deep hydrogeological circuit, which is chiefly hosted in the carbonate rocks and evaporites belonging to the Upper Triassic Verbicaro Unit (Iannace et. al., 2007). In particular, the warm deep reservoir has a temperature of ± 45 °C, as indicated by the chalcedony solubility and the SO4–F geothermometers. The warm reservoir is probably located at depths close to 0.9 km, assuming a geothermal gradient of 33 °C km-1. Water leaves the deep reservoir discharges at the surface at 37.3 ± 1.2 °C, with a SO4-Ca composition, after a relatively fast upflow and limited cooling.The upward part of hydrogeological circuit is controlled by local high-angle fault systems as well as by the tectonic window of Sambiase, where the Verbicaro Unit crops out.

This work studies the pollution of the beach sediments along the coastal sector between Crotone and Strongoli towns. 24 samples were investigated through grain size and chemical analyses. The samples are enriched in heavy metals as Ti, Fe, Ni, Co, Ce and V probably related to iron and magnesium minerals. Some samples are characterized by values of As, V, Co and Cr higher than the Italian low limits provided by D. Lgs. 152/2006. These anomalies can be ascribed to a combination of natural causes and anthropogenic activities.

Damavand is a Quaternary stratovolcano in N Iran, associated with small volumes of under-saturated to weakly-saturated mafic lavas (Tephrite-Basanite-Alkali olivine basalt), and large volumes of saturated lavas (trachyandesite-trachyte (TT)) together with minor pyroclastic rocks. TT rocks are characterized by LILE and HFSE enrichments, whereas the mafic rocks have higher REE and other incompatible elements (except Rb, Th) than TT suite rocks, contradicting the assumed derivation of TT magmas from mafic magmas by simple fractional crystallization processes. The similar whole-rock isotope ratios of mafic rocks, TT suites and their enclaves do suggest a common origin. Magmatic enclaves in TT suites show decoupled major and some trace elements from their host while they have similar geochemistry to the mafic lavas. Trace element modeling including assimilation-fractional crystallization (AFC) and energy-constrained recharge-assimilation fractional crystallization (EC-RAFC) suggest that the Damavand TT rocks were formed by multi-stage fractionation of mafic magma with minor effects of open system processes. Differentiation started at high pressures (6–8 kbar, initial temperature of magma (Tm) = 1180 °C) involving anhydrous minerals (mainly clinopyroxene-orthopyroxene), accompanied by recharge and wall-rock assimilation at equilibration temperature (Teq) of 1050 °C as the magma reached the threshold for extraction from crystal mush (Mm = 0.49) (stage-1). These processes resulted in the enrichment of the residual liquid in incompatible elements. The fractionation of oligoclase-andesine, anorthoclase, phlogopite and apatite from intermediate enriched melts occurred at shallow crustal levels (0.5–3 kbar, Tm = 1050 and Teq = 830 °C): here, FC processes and further recharge and assimilation of crustal materials reduced LILE and REE concentration in the residual liquid (stage-2). The role of enriched melts is supported by unusual trace element composition of key minerals, for instance, feldspars have variable concentrations of Ba (132–5495 ppm), Sr (1471-14413 ppm) and unusual Rb, La and Ce contents. Based upon melt extraction modeling, physical removal of residual melts at stage-2 could produce cumulate residues with trace element compositions comparable to enclaves in TT suites (stage-3). Disruption of crystal mush due to recharge, followed by mixing of enclave material with evolved trachytic melts caused buffering of magma at trachyandesitic composition (stage-4). The results affirm the advantages of using a range of compositional and textural records in modeling of petrogenetic processes in all magmatic plumbing systems.

The association among volcanism, tectonics and sedimentation may be critical for interpreting the paleogeographic and plate tectonic settings of the past. In modern and ancient sedimentary systems, volcaniclastic fragment classes have been distinguished on the basis of texture and composition. Criteria adopted for their temporal and spatial correlation with source volcanic areas, in terms of type of volcanism and particle-forming processes are still not well constrained and often a topic of controversy and misinterpretation. Here, we present data for volcaniclastic fragments occurring in modern beach sands of the Campanian coast of southern Italy, where there are two active volcanic areas, the Phlegrean Fields and Mt. Vesuvius. Despite their geographical proximity, these volcanoes are characterized by different magma compositions and eruptive mechanisms. We set out to test whether this translates into different textural and compositional characteristics of their associated volcaniclastic detritus in order to better constrain the criteria relating the type of volcanism to the nature of volcaniclastic sand fragments in the sedimentary record. Along a ~100 km coastal stretch, from the Volturno River mouth to Sorrento, 72 sand samples were collected mainly in beach berm environments. Detrital modes were defined for the medium sand fraction of each sample, where monocrystalline and lithic grains are easily identified. The analyzed samples show a mixed sedimentary and volcanic provenance. Samples from the northernmost coastal stretch show a sedimentary petrofacies at the Volturno River mouth. Bacoli marks the transition between the Apennine sedimentary and Phlegrean volcanic petrofacies. Along the Portici-Sorrento coastal stretch, volcanic lithic fragments dominate. Leucite and sanidine crystal components indicate that detritus from the Phlegrean Fields extends south from Licola to Naples Bay, whereas the Vesuvius provenance extends from Naples/Portici south to Castellammare di Stabia. Phlegrean Fields and Mt. Vesuvius volcaniclastic petrofacies have been discriminated through a different distribution of both compositions of the volcanic lithic fragments, leucite and K-feldspars content. Volcanic lithics with lathwork texture and leucite, are Mt. Vesuvius provenance source sensitive detrital grains, whereas volcanic lithics with vitric texture and K-feldspars marks the transition to the Phlegrean Fields petrofacies. The results formalize three different sandy petrofacies which were mapped from north to south as Sedimentary, Phlegrean (volcanic) and Vesuvius (volcanic) petrofacies.

Waters discharging at the Luigiane Spa come from two different hydrogeological circuits, which are chiefly hosted in the carbonate rocks and Upper Triassic evaporites of two distinct geological units, known as Verbicaro Unit and Cetraro Unit. The first unit contains a cold and relatively shallow aquifer behaving as a sort of piston-flow circuit with high flow rate, whereas the second unit encloses a warm and comparatively deep aquifer acting as a sort of well-mixed reservoir, where the circulation is slower and the rate is lower. Meteoric waters infiltrating along the Coastal Chain at similar elevations (615–670 m asl on average, in spite of considerable uncertainties) recharge both aquifers and, in the first case, acquire heat from rocks through conductive transfer as a consequence of deepening along a fault system and/or crossing between different systems, as suggested by local structural geology. In particular, the warm deeper reservoir has a temperature of ∼60 °C, as indicated by the chalcedony solubility and the Ca–Mg and SO4–F geothermometers, which were specifically calibrated for the peculiar water–rock-interaction (WRI) processes originating the Na–Cl–SO4 high-salinity warm waters that discharge at the Luigiane Spa. The warm deeper reservoir is probably located at depths close to 1.4 km, assuming a geothermal gradient of 33 °C km−1. The water leaving the deep reservoir discharges at the surface at 40.9 ± 3.3 °C after a relatively fast upflow and limited cooling. The upward part of both hydrogeological circuits is controlled by local low- and high-angle fault systems as well as by the tectonic window of Guardia Piemontese, where the Verbicaro Unit crops out and the Cetraro Unit approaches the surface. The reconstruction of this conceptual model has been made possible thanks to the adoption of a “local” approach integrating previously existing and new geological, hydrogeological and geochemical data and including the use of sulfur isotope data. This last technique has proven most important, as it enabled us to recognize the Upper Triassic fingerprint of dissolved sulfate, once the effects of bacterial sulfate reduction had been properly taken into account.

Reaction path modeling of water–rock interaction in a gneissic shallow aquifer of the Sila Massif was performed in kinetic (time) mode, under conditions of closed-system with secondary minerals and closed-system with CO 2 , to investigate the influence of both dolomite dissolution and biotite dissolution on the chemical characteristics of secondary vermiculites. Magnesium–Al- and calcium–Al-vermiculites are the major components of the vermiculite solid solution precipitated in the early stages of the process, which is dominated by dolomite dissolution. In contrast, Mg–Mg–Fe- and Ca–Mg–Fe vermiculites are important components of the vermiculite solid solution produced in the late stages of the process, where biotite dissolution prevails. Outcomes of this reaction-path-modeling exercise on vermiculite chemistry are fully consistent with the results obtained by Apollaro et al. (in press) through speciation–saturation calculations. In particular, Apollaro et al. (in press) showed that the pH of Mg–Al-vermiculite/Mg–Mg–Fe-vermiculite coexistence is 7.3. This value is virtually equal to the pH of Mg–Al-vermiculite/Mg–Mg–Fe-vermiculite iso-activity, 7.35, which is obtained from the results of reaction-path-modeling runs 3 and 4 carried out in this work.

Volcanic ash (1000 analyses) provides a basis for proximal-distal and distal-distal tephra correlations. Tephra deposits from the different Aeolian Islands are geochemically diverse; with some individual eruptions showing diagnostic geochemical heterogeneity recognised both stratigraphically and/or spatially. Major element glass analyses reveal that Vulcano (0-21ka) and Stromboli (4-13ka) have erupted potassic (shoshonitic and K-series) tephra with broadly overlapping compositions, but data presented here demonstrates that their eruptive products can be distinguished using either TiO2 contents or their HFSE/Th ratios. Whilst individual volcanic sources often produce successive tephra deposits with near identical major and minor element compositions through time (i.e., Lipari, Vulcano), trace element glass data can help to decipher successive eruptions. Changes in LREE and Th concentrations of volcanic glasses erupted spanning approximately the last 50ka greatly enhance the potential to discriminate successive eruptive units on Lipari. The new proximal glass database has been used to verify new (Ionian Sea; core M25/4-12) and existing distal occurrences of Aeolian Island derived tephra enabling the reassessments of past ash dispersals. Finally, proximal and distal data have been used to establish an integrated proximal-distal eruptive event stratigraphy for the Aeolian Islands.

Waters discharging at the Spezzano Albanese spring come from a deep circuit hosted in the Ophiolitic rocks of the Diamante Unit (phyllites and metabasalts, Liberi et al., 2006; Vespasiano et al., 2012b). The unit contains a warm deep aquifer acting as a sort of well-mixed reservoir; during the ascent the waters interact with Tertiary and Quaternary deposits (conglomerates, sands, gypsum and clays with levels of halite) that give them a characteristic composition with near neutral pH value of 7.05 to 7.57, outlet temperatures of 20.16° to 26.6°C, variable redox potentials (–0.25 to 0.28 V) and total dissolved solids from 848 to 9720 ppm.During deep circulation, the waters extract heat from reservoir rocks, attaining thermo-chemical equilibrium and rise relatively quickly to the surface, along sub-vertical faults and fractures, preserving part of their physical and chemical characteristics (Vespasiano et al., 2014).Water chemistry was discussed by means of the triangular diagrams among major anionic/cationic constituents and correlation plots. Triangular diagrams show a Na-Cl composition characterized by high bacterial sulfate reduction. Correlation diagrams attest a high calcite and silica precipitation (likely scaling effect) and show a 1:1 ratio between sodium and chlorine that underline an interaction with halite. This represents only a preliminary study that demonstrates the importance of the geochemical characterization as powerful tool to improve the knowledge of natural environment and to predict and avoid problems linked to the study of thermal sites (Gurrieri et al., 1984; Duchi et al., 1991; Italiano et al., 2010).

The study of the weathering process of ophiolitic rocks represents an important process due the high toxicity of Cr(VI) with environmental and social consequences and health effects.Since this topic is not well understood, a preliminary study on the release of Cr and other constituents during the weathering of the meta-ophiolitic rocks outcropping in Northern Calabria (Fuscaldo zone) has been carried out using the reaction path modeling.In this work, the EQ3/6 software package, version 8.0 was used together with its data0.ymp.R5 thermodynamic database (Apollaro et al., 2013a, b), upon acquisition of the necessary information such as the stability constants of the aqueous complexes of Cr(VI).Preliminary results showed that the geochemical modeling is an important tool to investigate the phenomena which control the redox state of Cr in near-surface environment and the release and fate of Cr and other chemical constituents in these peculiar environments since during the progressive dissolution of the considered lithotypes, the aqueous solution may attain saturation with respect to different secondary solid phases, potentially acting as sinks of various elements and species.

The progressive dissolution of metabasalts and serpentinites hosting the shallow aquifer of Mt. Reventino was simulated by means of the EQ3/6 software package, version 8.0, adopting both the Ideal Solid Solution Approach (ISSA) and the Double Solid Reactant Method (DSRM), which provided comparable results. A detailed field and laboratory study was performed on rock samples and local groundwaters to constrain and validate reaction path modelling. The prevalence of Ca–HCO3 over Mg–HCO3 compositions suggests that groundwaters interact chiefly with metabasalts and secondarily with the less abundant and less permeable serpentinites. The most important and active Cr source is a tremolite-rich amphibole, whose role as supplier of dissolved Cr has rarely been recognized in previous studies carried out in areas where ophiolitic rocks crop out. Speciation calculations indicate that hexavalent dissolved Cr is mainly present as chromate ion, followed by the neutral complexes CaCrO 4 o (14–32 mol%) and MgCrO 4 o (2–12 mol%), which are more mobile and more bio-available than charged solutes. All dissolved trace elements are supplied to shallow groundwaters by gradual dissolution of local rocks and, therefore, contributions linked to anthropogenic sources can be ruled out. In particular: (i) Ni is chiefly contributed to the aqueous phase by the tremolite-rich amphibole; (ii) different amounts of Sr, Ba, and Pb are provided by calcite dissolution (with Sr ≫ Ba > Pb), whereas the solid solution of orthorhombic carbonates acts as sink for these trace elements (with Xstrontianite ≫ Xwitherite > Xcerussite); (iii) the principal source of Cu and Zn is again calcite, whereas the solid solution of trigonal carbonates represents their major sink.

The Vulcanello peninsula is situated north of Vulcano, the southernmost island of the Aeolian Arc. It was built at the rim of La Fossa Caldera between 1000 and 1650 A.D. Erupted products are mafic to intermediate in composition, while the coeval products erupted inside the caldera are mainly rhyolitic. Therefore, Vulcanello’s activity represents an anomalous mafic post-caldera volcanism in a convergent setting. A petrographic and geochemical study was carried out on lavas and pyroclastic rocks representing the entire eruptive history of the volcanic centre. New data (major and trace elements and Sr isotope ratios on whole rocks, and major element compositions on mineral phases) and geochemical models were used to investigate shallow level differentiation processes ( i.e. , fractional crystallisation, fractional crystallisation plus crustal assimilation, degassing, magma mixing/recharge). The study suggests that the entire Vulcanello activity can be considered as the uninterrupted expulsion of a single deep magma batch of shoshonitic composition emitted from a NE–SW ring fault of La Fossa Caldera. The magma is genetically related to the shoshonitic basalts found as melt inclusions in the olivine crystals erupted in the products of the 1888–1890 “ La Fossa” activity. This points to a possible single deep plumbing system for both La Fossa Cone and Vulcanello centres, strongly controlled by NW–SE to N– S regional structures. The shoshonitic magma, undergoing fractional crystallisation, partly rose directly to the surface where two strombolian cones were constructed, while residual magma remained at depth, and, partially degassed and crystallised, it subsequently erupted both effusively to form a lava platform and explosively to form a third pyroclastic cone. The remaining magma evolved to latite by AFC process and was erupted both as a lava flow (Punta del Roveto) and in the form of pyroclastic products ( i.e. , the upper part of the third cone), controlled by shallow ring faults of La Fossa Caldera. Therefore the Vulcanello plumbing system is controlled by tectonic structures at depth and by shallower volcano-tectonic (caldera) fractures.

The volcanic products of Lipari Island (Aeolian Arc, Italy) younger than 10 ka are mostly aphyric rhyolitic pumices and obsidians emitted during unusual strombolian-type eruptions, which ended with the emplacement of lava flows. The last volcanic activity on the island dates back to 1230 ± 40 AD, with the extrusion of Rocche Rosse (RR) obsidian lava flow. Recently, mafic enclaves of latitic to trachytic composition have been identified and an evolution process between these enclaves and the rhyolitic magma has been documented in detail [Davi, M., 2007. The Rocche Rosse rhyolitic lava flow (Lipari, Aeolian Islands): magmatological and volcanological aspects. Plinius, supplement to the European Journal of Mineralogy 33, 1–8]. In this work textural and trace-element investigation of mineral phases of the RR enclaves, such as crystals of clinopyroxene, olivine, plagioclase, alkali-feldspar and biotite, was carried out to delineate the most recent feeding system of the island, since such a reconstruction could be significant in terms of hazard forecasting. The results indicate that most of the mineral phases are reversely or oscillatory zoned with respect to both major and trace elements, suggesting an early crystallization under low f O 2 conditions from melts of intermediate composition, followed by a later growth from a more mafic (presumably shoshonitic–basaltic) magma than that from which their cores crystallized. Crystals of magnesium-rich pyroxene and forsteritic-rich olivine are indicative of the presence of this shoshonitic basaltic magma. Based on microanalytical data, it is suggested here that the feeding system of recent Lipari volcanic activity was characterized by a shoshonitic–basaltic magma originating from a deep reservoir, which may have evolved and stopped in the crust, generating zoned magma chambers at different depths, in which latitic and rhyolitic magmas reside. The sudden arrival of a new input of mafic melt may have interacted with these resident fractionated magmas and triggered the eruption. A plumbing system of this type has been shown to be active in the southern sector of the Aeolian Islands since the last 42 ka [Gioncada, A., Mazzuoli, R., Milton, A., 2005. Magma mixing at Lipari (Aeolian Islands, Italy): Insights from textural and compositional features of phenocrysts. J. Volcanol. Geotherm. Res. 145, 97–118; Peccerillo, A., Frezzotti, M.L., De Astis, G., Ventura, G., 2006. Modeling the magma plumbing system of Vulcano (Aeolian Islands, Italy) by integrated fluid-inclusion geobarometry, petrology and geophysics. Geology 34, 17–20]. It is concluded that the hazard assessment of Lipari Island should take into account the arrival of deep and never erupted mafic melts as eruption triggers of more evolved shallower magma bodies.

This paper focuses on the main morphological, physical, chemical and mineralogical features of an andic-like soil, widely outcropping in the Sila upland plateau of Calabria (southern Italy), and its potential role in tephrostratigraphy. A multidisciplinary and multiscale approach allowed identification of this soil as a “masked” distal archive of volcanic products, developed on granite rocks and sediments with a coeval pyroclastic input during pedogenesis. The study demonstrates that the contribution of volcanic parent materials can be successfully hypothesized and assessed even in the absence, limited extent or poor preservation of primary eruptive products. The soil has an Andisol-like appearance, despite laboratory data that do not match the entire suite of diagnostic criteria for the Andisol taxonomic order. Geomorphological, stratigraphic and pedologic results, coupled with tephrostratigraphic and radiometric data, concur to suggest a Late Pleistocene(?) to Holocene age of the Andisol-like soil. In particular, the rhyolitic chemical composition of small-sized glass fragments (identified by SEM–EDS analyses) indicates soil genesis contributed by volcanic ash, probably sourced from Aeolian Arc explosive activity spanning the last 30 ka. Accordingly, the evidence of limited relict clay illuviation and the specific type of pedogenesis allowing the development of andic properties (in turn related to the neoformation of clay minerals from the weathering of volcanic glass) are consistent with a climatic shift from a seasonally-contrasted to a constantly humid pedoenvironment. This change can be ascribed to the Lateglacial(?) or Early–Middle Holocene to Late Holocene transition. Calibrated AMS 14C dates performed on charcoal fragments sampled from three representative soil profiles, provide Late Holocene ages (3136 ± 19, 343 ± 16 and 92 ± 24 yr BP), in accord with archaeological finds. On the basis of the consistent stratigraphic position, lateral continuity and wide extent, the soil can be considered a good pedostratigraphic marker in the Sila highlands and is informally defined as the “Cecita Lake geosol”. It supplies valuable time constraints for the underlying (occasionally overlying) deposits and/or soils. Moreover, it allows regional-scale morphostratigraphic correlations and detailed reconstruction of Late Pleistocene–Holocene geomorphic events in Calabria, a very suitable region for distal tephra deposition in the central Mediterranean peri-volcanic area. The effects of high-energy volcanic eruptions are interfingered with or superimposed by other geomorphic processes and climatic or anthropogenic signals.

Stratigraphic reconstruction of the Upper Pollara eruption has allowed for the inference of eruptive mechanisms and the distillation of a sedimentological model for pyroclastic density currents (PDCs) moving across variable topography. The pre-eruptive topography in the study area was characterised by a tuff ring-like morphology, with both inward and outward dipping slopes. Highly viscous, moderately porphyritic, dacitic to rhyolitic magmas fed the eruption, which was characterised by a Vulcanian eruptive style. The stratigraphic succession was divided into five eruption units (EUs), which result from different phases of the eruption separated by stases. Sustained columns occurred only during EU1, while PDC generation dominates EU2–5. Lithofacies analysis of the PDC deposits indicates the prevalence of massive coarse-grained deposits on the inner slopes of the Pollara crater, which are interpreted as the deposits of a flow-boundary zone dominated by granular flow or fluid escape regimes. Dune-bedded, massive to stratified lithofacies dominate the outer slopes of the Pollara crater, and are interpreted as the deposits of PDCs with flow-boundary zones in which traction played a major role. Thin, massive PDC deposits are exposed on the sub-horizontal Malfa terrace, and are interpreted as representative of flow-boundary zones dominated by a granular flow regime. The occurrence of stacked deposits indicates that most of the PDCs were characterised by unsteady pulsatory behaviour, with development of trains of pulses during their transport. The downcurrent lithofacies transitions observed for the Upper Pollara deposits have finally been compared with other similar lithofacies associations which have been described for short-lived PDCs at tuff rings, in order to discuss the influence of pre-eruptive topography on lithofacies association.

Geochemical study allowed to recognize four groups of groundwater for the Sibari Plain (Southern Italy): Ca-HCO3, Na-Cl, Ca-Cl and Na-HCO3. Chloride-rich waters are located close to the Crati mouth that could be a preferential path for seawater ingression. In fact, seawater and brackish waters could move inland along the stream channel and enter the nearby aquifers due to excessive pumping of wells positioned near the river. In alternative, the occurrence of processes, such as ion exchange or dissolution of halite-bearing Miocene evaporite deposits can generate aqueous solutions with similar characteristics to those produced by seawater ingression. Moreover, was calculated the infiltration average (Hi, m a.s.l.) for groundwater of the Sibari Plain by the following equations: The data showed a lower average of the infiltrations in the inner part of the Sibari Plain, with values between 550 and 870 m a.s.l., and higher values (1000/1500 m a.s.l.) moving to NW and SE.

This work shows the granulometric, mineralogical and micromorphoscopic data of the Alimini (Lecce, Apulia) beach, an important touristic site with a strong erosive rate. Our study demonstrates that the sediments forming the sands are rarely related to the carbonatic rocks outcropping in the area. Rather, they are mainly represented by heavy minerals and quartz of volcanic and metamorphic origin. The presence of peculiar mineral phases as the melanitic garnet points to a provenance from the Vulture volcano. However, the occurrence of quartz, microcline and piralspitic garnets points to a simultaneous feeding from the southern Appenninic units. Sediments are probably eroded and transported by the Ofanto river. The high roundness of the grains witnesses the long transport along the coast and, probably, also the continuous recycle from the dune to the beach and vice versa.

The role of both natural weathering and anthropogenic pollution in controlling the distribution of major oxides and several trace elements in soils, stream sediments, and rocks of the Fiume Grande catchment was evaluated. The contents of major oxides and trace elements in soils appear to be governed by weathering and pedogenetic processes, although the use of fertilizers in agriculture could also partly affect K2O and P2O5 contents. Stream sediments have concentrations of major oxides (except CaO) very similar to soils, as relevant amounts of soil materials are supplied to the stream channels by erosive phenomena. In contrast, stream sediments have concentrations of Cr, Co, Ni, Zn, As, and Pb significantly higher than those of soils, probably due to different conditions and rates of mobility of these elements within the three considered matrices and/or disposal of wastes in the drainage network. Comparison of the concentrations of PHEs in soils with the maximum admissible contents established by the Italian law shows that these limits are too restrictive in some cases and too permissive in other ones. The approach of setting these limits with no consideration for the local geological–geochemical framework may lead to improper management of the territory and its resources.

Exposure to lead (Pb) may affect adversely human health. Mapping soil Pb contents is essential to obtain a quantitative estimate of potential risk of Pb contamination. The main aim of this paper was to determine the soil Pb concentrations in the urban and peri-urban area of Cosenza–Rende to map their spatial distribution and assess the probability that soil Pb concentration exceeds a critical threshold that might cause concern for human health. Samples were collected at 149 locations from residual and non-residual topsoil in gardens, parks, flower-beds, and agricultural fields. Fine earth fraction of soil samples was analyzed by X-ray Fluorescence spectrometry. Stochastic images generated by the sequential Gaussian simulation were jointly combined to calculate the probability of exceeding the critical threshold that could be used to delineate the potentially risky areas. Results showed areas in which Pb concentration values were higher to the Italian regulatory values. These polluted areas were quite large and likely, they could create a significant health risk for human beings and vegetation in the near future. The results demonstrated that the proposed approach can be used to study soil contamination to produce geochemical maps, and identify hot-spot areas for soil Pb concentration.

Upper Pollara eruption products (13 ka, Salina Island, Italy) include both homogeneous and heterogeneous pumices resulting from mixing/mingling processes between an HK andesite and a high-SiO2 rhyolite. Representative samples of heterogeneous pumices are collected and analyzed in order to check the correspondence between glass composition and morphological features of the mingling/mixing structures. Image analysis techniques are applied and eight grey color ranges (classes) are extracted from high-resolution scans of pumice. Class 1 (lighter colors) and class 8 (darker colors) show end-member glass compositions, i.e. HK andesite and high-SiO2 rhyolite, respectively. These two classes show spot- to cluster-like morphological structures. Intermediate classes show an HK dacitic to rhyolitic composition and a banding- to fold-like morphology. Fractal analysis by box-counting of the boundary pattern of eight grey classified images is performed over a length scale of 0.028–1.8 cm. Fractal dimension D is between 1.01 and 1.84. Coupled fractal analysis and geochemical data reveal that D increases as the degree of magma interaction (homogenization) increases. This feature well fits the results from numerical models on the convective mixing of fluids driven by thermal convection. We conclude that the increase of D observed in the Upper Pollara samples reflects the transition from fractal mixing to homogenization. End-member magmas (HK andesite and high-SiO2 rhyolite) represent isolated mixing regions, while homogenized magmas represent active mixing regions. In the analyzed pumices, isolated and active mixing regions coexist at scales between 10−4 and 10−2 m. Morphological and compositional features of the Upper Pollara pumices result from turbulence.

Lava flows and pyroclastic deposits from strombolian fallout related to the activity of the Rivi and Capo volcanoes, which are representative of early subaerial volcanoes on Salina (Aeolian Islands), have been investigated through a geological–petrological approach. Our geological field survey shows that Rivi and Capo volcanoes are part of a single N50°E aligned volcanic complex, here named Rivi–Capo Volcanic Complex (RCVC). Stratigraphically specific rock sampling has allowed reconstruction of the magma feeding processes through time. Whole rock major element compositions, together with core-to-rim profiles of plagioclase and clinopyroxene crystals, show a general evolution toward more basic compositions through the three formations constituting the Capo volcano and within the Rivi center. MELTS simulations and mass balance modeling suggest that the RCVC rocks are the result of fractional crystallization of plagioclase, clinopyroxene, and olivine (ca. 45 % of solid removed) from a primary magma. In addition to fractional crystallization, continuous recharge and mixing with more basic magma coming from deeper parts of the magmatic plumbing system contributed to the final volcanic rock compositions. Our textural and microanalytical data on plagioclase and clinopyroxene crystals allow the definition of a multilevel magmatic storage system with reservoirs at ~20 and ~3 km below sea level. When processes of magma differentiation, ascent, and storage are considered together with the stratigraphic position of each sample, a history of continuous modification of the RCVC plumbing system can be constructed. Volcanism may have been characterized by fissure-type eruptions during the early stages (Lower Capo, Lower Rivi, and Middle Capo Formations), gradually changing later to central-type volcanism (Upper Capo and Upper Rivi Formations).

Characterization of spatial variation of heavy metals in urban soils is essential to identify pollution sources and potential risks to humans and the environment. While heavy metals concentration in soils depends also on the nature of bedrock and on abiotic and biotic factors, it can be argued that nowadays, due to increasing human activities, it is determined mainly by anthropogenic sources. We determined concentrations and spatial distribution of heavy metals, with particular focus on those potentially toxic (As, Cr, Pb, V, and Zn), in urban and peri-urban soils of Cosenza-Rende (southern Italy). One hundred forty-nine samples of topsoil (0-10 cm) were collected and analyzed for 36 elements by X-ray fluorescence spectrometry and inductively coupled plasma mass spectrometry (ICP-MS). In addition, 18 samples of rocks were collected on outcrops of whole area and analyzed by ICP-ES and ICP-MS. Geostatistical methods were used to map the concentrations of major oxides and several minor elements. Heavy metals in the analyzed samples showed a wide range of concentrations, primarily controlled by the geochemical composition of bedrock, with the notable exceptions of Cu, Pb, and Zn, whose concentrations are heavily affected by land use and anthropogenic pollution in urban areas. Geochemical analysis and spatial distribution showed that high concentrations of potentially toxic elements are found in soils near major roads, indicating that anthropogenic factors determine the anomalies in these areas. © Springer Science+Business Media B.V. 2012.

The Tufiti di Tusa Formation, a siliciclastic turbidite system of lower Miocene age in southern Italy, is mainly composed of volcaniclastic and quartzolithic sandstones interbedded with mudrocks. Sandstones are subdivided into four distinctive petrofacies, evolving from quartzolithic to volcaniclastic lithofeldspathic and feldspatholithic, reflecting detrital evolution from growing orogen (quartzolithic petrofacies) to active volcanism (volcaniclastic petrofacies). The mineralogical composition of the associated mudrocks is predominantly characterized by phyllosilicates, mainly illite/smectite mixed layers (I/S R1 associated with minor amounts of I/S R0 in the lower part of the succession, and I/S R3 in its upper part), together with illite, detrital micas and chlorite, and minor amounts of chlorite/smectite mixed layers and kaolinite, in addition to quartz, calcite and feldspars. The most abundant phyllosilicates are I/S mixed layers, 10-Å minerals (illite and micas) and chlorite, while kaolinite and chlorite–smectite mixed layers are present as a few per cent or in trace amounts. X-ray diffraction patterns show the occurrence of the ordered I/S R1 mixed layers in most samples but, at the top of the succession, some samples are characterized by I/S R3 mixed layers, whilst in the lower part of the succession I/S R1 is associated with a lower amount of I/S R0. These features suggest that the Tufiti di Tusa Formation experienced a medium diagenetic grade, and the occurrence of I/S R3 could be explained by K-availability in samples in the upper part of the succession. The lithic fragments in sandstones are metasedimentary rocks of Palaeozoic age, and andesite to dacite volcanic rocks of early Miocene age. The associated mudrocks also contain trace element ratios (Cr/V, Y/Ni, La/Sc, Th/Sc, Th/Co, Th/Cr, Cr/Th and Eu/Eu*) consistent with a provenance containing intermediate to silicic sources with scarce or absent basic rocks. The chemical index of alteration (63.2 to 71.6) suggests a moderate degree of weathering in the source. Furthermore, the K/Cs ratios of sediments confirm likely moderate rather than intense weathering. The index of compositional variability (ICV) values (from 1.2 to 2.5) are high enough to suggest the mudrocks are first-cycle sediments with little recycling. The Al–Ti–Zr diagram and the Th/Sc v. Zr/Sc plot indicate poor sorting and rapid deposition of the sediments. Detrital and sedimentary evolution of the Tufiti di Tusa Formation provides constraints, in terms of relations between a growing orogenic system and active volcanism in the Central Mediterranean, to contribute to geodynamic and palaeogeographic reconstructions of the earliest collision in the southern Apennines region.

The Pollara tuff-ring resulted from two explosive eruptions whose deposits are separated by a paleosol 13 Ka old. The oldest deposits (LPP, about 0.2 km3) consist of three main fall units (A, B, C) deposited from a subplinian column whose height (7–14 km) increased with time from A to C, as a consequence of the increased magma discharge rate during the eruption (1–8x106 kg/s). A highly variable juvenile population characterizes the eruption. Black, dense, highly porphyritic, mafic ejecta (SiO2=50–55%) almost exclusively form A deposits, whereas grey, mildly vesiculated, mildly porphyritic pumice (SiO2=56–67%) and white, highly vesiculated, nearly aphyric pumice (SiO2=66–71%) predominate in B and C respectively. Mafic cumulates are abundant in A, while crystalline lithic ejecta first appear in B and increase upward. The LPP result from the emptying of an unusual and unstable, compositionally zoned, shallow magma chamber in which high density mafic melts capped low density salic ones. Evidence of the existence of a short crystal fractionation series is found in the mafic rocks; the andesitic pumice results from complete blending between rhyolitic and variously fractionated mafic melts (salic component up to 60 wt%), whereas bulk dacitic compositions mainly result from the presence of mafic xenocrysts within rhyolitic glasses. Viscosity and composition-mixing diagrams show that blended liquids formed when the visosities of the two end members had close values. The following model is suggested: 1. A rhyolitic magma rising through the metamorphic basement enterrd a mafic magma chamber whose souter portions were occupied by a highly viscous, mafic crystal mush. 2. Under the pressure of the rhyolitic body the nearly rigid mush was pushed upwards and mafic melts were squeezed against the walls of the chamber, beginning roof fracturing and mingling with silicic melts. 3. When the equilibrium temperature was reached between mafic and silicic melts, blended liquids rapidly formed. 4. When fractures reached the surface, the eruption began by the ejection of the mafic melts and crystal mush (A), followed by the emission of variously mingled and blended magmas (B) and ended by the ejection of nearly unmixed rhyolitic magma (C).

A geochronological study of the Filicudi, Salina, Lipari and Vulcano Islands (Aeolian Archipelago) using the unspiked potassium–argon technique provides new age data which, combined with stratigraphic correlation, better constrain the temporal evolution of volcanism. The unspiked K–Ar age of the oldest exposed lavas on Filicudi, 219±5 ka, is significantly younger than the previous estimation of 1.02 Ma. In the general context of Aeolian volcanism, this new date suggests that the volcanism of the western sector of the Aeolian Archipelago is younger than previously thought. Geochronological data point out on the rapid transition from calc–alkaline to potassic volcanism. The distribution of the K–Ar ages within the Salina–Lipari–Vulcano group shows that the volcanism started on Lipari and propagated over time northward on Salina and southward on Vulcano. Geochronological and geophysical data suggest that the onset of volcanism in the central sector of the Aeolian Arc may be due to a mantle upwelling structure located below Lipari. A change in the style of the eruptions occurred in the Salina–Lipari–Vulcano system at about 100 ka from the present. Low-energy magmatic eruptions occurred between 188 and about 100 ka. From about 100 ka to the present, higher-energy eruptions and low-energy events due to magma–water interaction also occurred. This change in the style of activity, together with the appearance of evolved products (i.e. rhyolites) during the last 50 ka, is consistent with the formation of magmatic reservoirs located at shallower depth with respect to those of the 188–100-ka period. The new geochronological data and available petrological models reveal that a change in the deep source of the primary magmas occurred in a relatively short time interval.

The base-surge products of the Monte Guardia sequence on Lipari contain evidence suggesting that magma mixing accompanied the main eruption. Principal data include at least two essential glass populations with discrete compositions, dominance of crystals that are incompatible with the rhyolitic glass, and contrasting quench and superheating textures in the various types of glass pryoclasts. Four distinct types of non-phenocrystic essential pyroclasts are present: vesicular white glass, non-vesicular white glass, brown devitrified clasts, and black microcrystalline clasts. The first three clast types have a uniform rhyolitic composition that is quite distinct from the alkali trachytic composition of the fourth type. These latter black microcrystaline grains have a wide range of compositions that fall in the trachyte field. Discrete crystal grains also occur as essential pyroclasts. The dominant crystal phases are augite and bytownite, with minor amounts of orthopyroxene, olivine pseudomorphed by iddingsite, magnetite, ilmenite, and sanidine. Biotite and hornblende are trace constituents. The diverse mineral assemblage and composition of the most abundant crystals suggest that their origin is different from that of the rhyolitic clasts. Pyroclast textures indicate that these magmas of different composition have been intimately mixed during eruption. The cryptocrystalline textures of the trachyte pyroclasts is due to their chilling within the rhyolitic magma. Strongly vesiculated rhyolite and glass in contact with augite and bytownite crystals suggests that these crystals were able to locally cause exsolution of volatiles. These relationships suggest a separate source for the mafic crystals, and discrete chambers for the trachytic and rhyolitic glass. The eruption model thus involves the mixing of two magmas during the interaction of the erupting materials with near-surface (sea) water.

The Terme Sibarite and nearby thermomineral water discharges have Ca-SO4 to Ca-SO4-HCO3 composition, near neutral pH value of 6.9 to 7.6, outlet temperatures of 16° to 25.5°C, variable redox potentials (-0.23 to 0.2 V) and total dissolved solids from 20 to 35 meq L-1. The total flow rate of the Terme Sibarite springs is about 130 L s-1. Solubility of chalcedony and the K-Mg geothermometer show a full equilibrium reservoir temperature of 33°C. The ?34S values of dissolved sulfate are constrained by mixing of thermomineral waters with cold waters, both interacting with Upper Triassic carbonate-evaporite rocks, as well as occurrence of bacterial sulfate reduction. In the light of the geological and hydrogeological framework of the study area, this chemical and isotopic evidence suggests that the thermal circuit develops entirely into the Upper Triassic sedimentary sequence, without any interaction with the Messinian evaporites which are possibly present below the Upper Triassic sedimentary sequence. The thermomineral waters are meteoric precipitations infiltrating in the Pollino Massif, at average altitudes of 950-1090 m a.s.l, as indicated by the ?18O values of water. These waters descend to maximum depths of 600 m below the Sibari Plain, where the geothermal reservoir is situated. Circulating into it, waters extract heat from reservoir rocks, attaining thermo-chemical equilibrium at the temperature suggested by chemical geothermometers. Then, the thermomineral waters locally rise relatively quickly to the surface, along subvertical faults and fractures, preserving part of their physical and chemical characteristics. The methodological approach utilized in this research may be applied to other fault-controlled, low-temperature geothermal systems in other zones of Italy and other nations.