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The vast majority of extrusive carbonatites are calcitic rocks which may be confused with sedimentary limestones, thus requiring a disambiguation criterion. Extrusive carbonatites are classified based on quantitative criteria that tend to avoid genetic mechanisms. Carbonatite nomenclature is in progress but regulated by the International Union of Geological Sciences norm for igneous rocks. Carbonate sedimentary rock nomenclature is mainly regulated by the Dunham, Embry and Klovan, and Sibley and Gregg classification systems. These limit the description of rock types from various depositional mechanisms and makes comparison with sedimentary rocks difficult. Igneous and sedimentary carbonate rocks display no apparent differences in the field and at meso–micro-scale. They may be layered, massive crystalline or show discrete clasts in a matrix, which make both rock types resemble one another. The study analyses the situations in which classification inconsistencies are most common. Adopting these guidelines may increase confidence, reliability and value in the petrographic classification of igneous and sedimentary lithologies. This study poses a challenging target. Can igneous carbonate rocks be classified using the same approach that is used for sedimentary carbonate rocks and vice versa? So far, the scheme chosen has been arbitrary or limited to the aim of the study being undertaken. The authors start an unexperienced dialogue for the first time between volcanologists and sedimentologists by examining a range of sedimentary and volcaniclastic rock textures which may resemble each other.

This paper represents an interdisciplinary research focused on the microscopic and mineralogical investigations of the original fragments of a precious medieval painting, a rare byzantine Dormition of the Virgin in Italy. The painting has discovered in the rural monastery of Santa Maria del Rogato (Sicily), thanks to a recent restoration work. In order to obtain an exhaustive description of both the original mortars and pigments, several investigation methods are employed, from optical, polarization-fluorescence and electron microscopies, elemental analyses and X-ray diffraction as well. The experimental analyses, useful as a guideline in the restoration, allowed to the knowledge of the original materials as well as of the techniques used to realize the artwork. The paintings are realized by a fresco technique, by using lime and a simple color palette, based on natural earth, as typical of the Byzantine pictorial tradition.

We investigated hellandite-group mineral phases from the Roman Region, alkali syenite ejecta, by multimethod analyses. They show a complex crystallisation history including co-precipitation of hellandite-(Ce) with brockite, resorption, sub-solidus substitution with mottanaite-(Ce), exsolution of perthite-like ferri-mottanaite-(Ce), overgrowth of an oscillatory-zoned euhedral shell of ferri-mottanaite-(Ce) and late, secondary precipitation of pyrochlore in the cribrose hellandite-(Ce) core. LREE/HREE crossover and a negative Eu anomaly in hellandite-group minerals follows fO2 increase during magma cooling. The distinction among the hellandite-group minerals is based on the element distribution in the M1, M2, M3, M4 and T sites. Additional information on miscibility relationship among the hellandite sensu strictu, tadzhikite, mottanaite, ferri-mottanaite and ciprianiite endmembers derives from molar fraction calculation. We observed that change in composition of hellandite-group minerals mimic the ligands activity in carbothermal-hydrothermal fluids related to carbonatitic magmatism.

Discrete zircons, up to 9 mm in length, occur in alluvial deposits from the Veneto area. They are likely derived from the disaggregation of lamprophyric rocks belonging to a regional, pervasive dyke-swarm. Zircon and REE phases occur in both alkaline lamprophyres and connate calcite-bearing felsic lithics and their debris in lamprophyre breccia. We present 36 new complete U–Pb and trace element analyses of zircons and associated inclusions. We used a statistical approach on a larger dataset using new and literature data to evaluate the confidence figure to give an estimation of age of zircons. Inclusions suggest a genetic link with an S–CO2–ZrO–BaO–SrO–CaO-rich fluid/melt possibly associated with carbonate-rich alkaline parental magma and a metasomatised mantle source. This paper confirms the importance of calcite–syenite and lamprophyre genetic link and zircon magmatic origin, in contrast with hydrothermal and metamorphic zircons. U–Pb dating by LA-ICP-MS provides time constrains (40.5–48.4 Ma, Lutetian), consistent with the age of the alkaline magmatic event. Trace element data indicate a link to anorogenic magmatism associated with mantle upwelling. Complex zoning is highlighted by cathodoluminescence images. The Veneto zircons are helpful for regional geological information and may have commercial potential as a critical resource for green technologies.

Atmospheric particulate matter (PM) is one of the pollutant that may have a significant impact on human health. Data collected during three years in an urban area of the Adriatic coast are analysed using three models: a multiple linear regression model, a neural network model with and without recursive architecture. Measured meteorological parameters and PM10 concentration are used as input to forecast the daily averaged concentration of PM10 from one to three days ahead. All simulations show that the neural network with recursive architecture has better performances compared to both the multiple linear regression model and the neural network model without the recursive architecture. Results of PM forecasts are compared with the air quality limits for health protection to test the performance as operational tool. The inclusion of carbon monoxide (CO) concentration as further input parameter in the model, has been evaluated in terms of forecast improvements. Finally, all models are used to forecast the PM2.5 concentration, using as input the meteorological data, the PM10 and CO concentration, to simulate the situation when PM2.5 is not observed. The comparison between observed and forecasted PM2.5 shows that the neural network is able to forecast the PM2.5 concentrations even if PM2.5 is not included among the input parameters.

The main goal of this study was to identify Gram-negative bacteria resistant to antibiotics, in particular β-lactams, in stream waters and effluents from urban wastewater treatment plants draining into Fino, Tavo, and Saline rivers of the Abruzzo region, Italy. Eight sampling sites were selected because they were the most contaminated by coliforms during previous sampling campaign. One sample for each site was collected for the detection of total and fecal coliforms

The Quaternary Fucino basin in the central Apennines of Italy was struck by one of the strongest Italian earthquakes of the last millennium (1915, Mw 7.0). The Avezzano town, ~ 9.0 km away from the epicentre, was completely destroyed. In the surrounding area sizable coseismic surface deformation were catalogued, attesting the severity of earthquake, the proximity to the causative fault and the geological and geomorphological complexity of a basin filled by thick lacustrine sediments. The Avezzano area provides a case study to understand how shallow subsurface geology influences site effects in a deep Quaternary continental basin environment, thus being of potential interest for similar geologic contexts worldwide. Within the investigated area, different possible earthquake-induced effects can occur, such as a) stratigraphic amplifications in a wide range of resonance frequencies (from 0.4 to 15–20 Hz); b) liquefaction; c) coseismic surface faulting; d) basin-edge effects; and e) slope instability. We present and discuss results of basic seismic microzonation study (SM) of the Avezzano area, focusing on geologic constraints aimed at the reconstruction of the shallow subsurface geology, and associated potential for local seismic hazard. We adopted an interdisciplinary approach based on detailed geological-structural, geophysical and seismic analyses to investigate the seismic response of high-seismic risk area, such as the Avezzano town, given the urban and industrial expansion since the last century. We discuss methodological approaches and their uncertainties.

In this paper, we investigate a conservation treatment on different kinds of Agrigento’s biocalcarenites, introducing a new non-commercial aqueous nanolime suspension for compatible and eco-friendly extensive applications. This nanolime, here tested for the first time, can be considered a green treatment for both the environment and the health of the conservator. Petrographic, chemico-physical and mechanical investigations of the different biocalcarenites were carried out before and after treatment application. This new nanolime yielded a very promising consolidation effectiveness for all the biocalcarenites, increasing the superficial cohesion and the drilling resistance without significantly altering the stone porosity or the aesthetical features.

A new discovery of carbonatites at Pianciano, Ficoreto and Forcinelle in the Roman Region demonstrates that Italian carbonatites are not just isolated, mantle xenoliths-bearing, primitive diatremic rocks but also evolved subtype fluor-calciocarbonatite (F ~ 10 wt%) associated with fluor ore (F ~ 30 wt%). New data constrain a multi-stage petrogenetic process, 1-orthomagmatic, 2-carbothermal, 3-hydrothermal. Petrography and geochemistry are conducive to processes of immiscibility and decarbonation, rather than assimilation and crystal fractionation. A CO2-rich, ultra-alkaline magma is inferred to produce immiscible melilite leucitite and carbonatite melts, at lithospheric mantle depths. At the crustal level and in the presence of massive CO2 exsolution, decarbonation reactions may be the dominant processes. Decarbonation consumes dolomite and produces calcite and periclase, which, in turn, react with silica to produce forsterite and Ca silicates (monticellite, melilite, andradite). Under carbothermal conditions, carbonate breakdown releases Sr, Ba and LREE; F and S become concentrated in residual fluids, allowing precipitation of fluorite and barite, as well as celestine and anhydrite. Fluor-calciocarbonatite is the best candidate to exsolve fluids able to deposit fluor ore, which has a smaller volume. At the hydrothermal stage, REE concentration and temperature dropping allow the formation of LREEF2+ and LREECO3+ ligands, which control the precipitation of interstitial LREE fluorcarbonate and silicates: (bastnäsite-(Ce), Ce(CO3)F and britholite-(Ce), (Ce,Ca)5(SiO4,PO4)3(OH,F). Vanadates such as wakefieldite-(Ce), CeVO4, vanadinite, Pb5(VO4)3Cl and coronadite Pb(Mn4+ 6 Mn3+ 2)O16 characterise the matrix. At temperatures of ≤100 °C analcime, halloysite, quartz, barren calcite, and zeolites (K-Ca) precipitate in expansion fractures, veins and dyke aureoles. © 2019 The Authors 689909 IGM SD RAS 0330-2016-0005 The HiTech AlkCarb European Union Horizon 2020 project grant-agreement number 689909 supported this research. Mineralogical studies was also partly supported by the Russian State assignment project IGM SD RAS 0330-2016-0005.

Assessment of the isotope systematics and the magmatotectonic history of mainly Cenozoic igneous rocks from Italy shows them to be inconsistent with subduction-related magmatism. We attempt to fit these data into an alternative model involving long-term, recurrent plume activity that extended over a period of about 100 Ma, that involved mantle expansion and subsequent mixing between isotopically-distinct, mantle components. Sr, Nd and Pb isotopic compositions of Cenozoic Italian igneous rocks, rather than being random, reflect binary mixing involving a common end-member similar to FOZO. Most isotopic data from along the entire length of Italy, from the Aeolian Islands to the Alpine belt, define a Main Italian Radiogenic Trend (MIRT), characterized by mixing between FOZO and a highly radiogenic Sr, mantle end-member (ITEM, ITalian Enriched Mantle). Data from the Adria foreland, Sicily and the south-western Tyrrhenian Sea and Sardinia deviate from MIRT suggesting mixing with other components, perhaps HIMU and EM1. Both the absence of pure DMM, and the presence of isotopic end-members not recognized in present-day consuming-plate margins are incompatible with subduction-related models. Two models are discussed, one in which ITEM is attributed to melting of pre-Alpine sediments/upper continental crust entrained in a FOZO-like mantle and the other to widespread metasomatic activity involving deep-seated plume activity. In the latter, the widespread nature of FOZO is attributed to a late Triassic–early Jurassic plume that preceded the opening of the Alpine Tethys and led to modification of the lithosphere and/or asthenosphere. Late Jurassic–early Cretaceous plume activity produced mantle expansion and the opening of the Alpine Tethys. A new phase of plume activity started during the Oligocene with the opening of the western and central Mediterranean Basins. Stretching and large-scale extension of the Mediterranean lithosphere was caused by the progressive eastward growth and volume increase of a plume head trapped within the Transition Zone. Plume-generated fluids/melts enriched in K–Ca–CO2–H2O, produced mantle sources capable of generating widespread alkaline, mafic, and carbonatitic magmatism. Lithospheric unloading controlled the Tyrrhenian and peri-Tyrrhenian magmatic activity.

We present detailed geological investigations aimed at the reconstruction of the shallow subsurface geology, and associated local seismic hazard, of the Avezzano town in the Quaternary Fucino basin (central Apennines). This work shows a basic (Level 1) seismic microzonation (SM) of the Avezzano town, focusing the attention on geologic constraints. We also discuss some methodological procedures of SM. Level 1 SM involves a reconstruction of the subsurface geological model achieved by a multidisciplinary approach synthesized in two main thematic maps and geologic sections. The first map, containing essential geologic information, is formed by overlapping layers (geological units, litho-technical units, and geomorphological/structural features). The second map is a summary map, easily accessible to non-geologist earthquake scientists/technicians, which synthesizes surface geology, subsurface data and resonance frequencies into homogeneous microzones. The two maps are tools for land and urban planning. The Avezzano area provides a case study of shallow subsurface geology and site effects in a deep continental basin environment, and is of potential interest for similar geologic contexts worldwide. Within the investigated area, almost all the possible earthquake-induced effects can occur, such as (a) stratigraphic amplifications in a wide range of resonance frequencies (from 0.4 to > 10 Hz); (b) liquefaction; (c) coseismic surface faulting; (d) basin-edge effects; and (e) slope instability.

This paper reports significant results about the effects of repeated treatments to protect a mediaeval Italian mortar from capillarity-absorbed water, by using for the treatments, our no-commercial hydro-alcoholic suspensions ofcalcium hydroxidenanoparticles(nanolime). The mortars samples came from the historical site, where preliminary thermographic inspection were performed to detect the damp zones. Before treatments, the samples were analyzed from a mineralogical and chemical point of view, by means of several techniques, asoptical microscopy(OM), thin section observations (PFM), porosimetric investigations, X-ray fluorescence (XRF), X-ray diffraction (XRD),infrared spectroscopy(FT-IR) and thermal analysis (TG-DTA). The size-grading curve of the aggregate and the binder/aggregate ratio were examined too. Then, the efficacy of nanolime protective treatments on this mortar versus the nanolime concentrations was investigated. For this aim, capillarity tests as well as porosimetric investigations, before and after the treatments, were performed. The obtained results were remarkably promising both in terms of the reduction of water absorbed by capillarity (up to 60%) together with an adequate decrease of porosity (up to 23%), fixing the protective effect of such eco-friendly and very compatible approach.

The eroded Colle Fabbri volcano comprises intrusive and extrusive rocks which cover an area of about 10,000 m 2 in the Umbria region, Central Italy. The outcrop is located at the SW boundary of the Umbria Valley Graben (Umbria Region) on an N140 normal fault inside the Intramountain Ultra-Alkaline Province of carbonatite and melilitite rocks of central–southern Italy. A field survey of the outcrop allowed a reconstruction of igneous activity events of this unusual small-scale volcano. It is younger than 0.7 m.y. and rests on Lower Pleistocene conglomerates with intercalated clay beds. A palaeosoil marks the base of the volcanic sequence. It follows several metres of extrusive breccias composed of fragments of thermometamorphosed clay and travertine. Key features of these breccias are mud shells on blocks, plastic mud lumps, slumps, and mechanical injection from one layer into another, as well as plastic and vesiculated, micro-brecciated matrix. The breccias are cemented by a variety of silicate, sulphate, and sulphate–carbonate minerals deposited by intense hydrothermal circulation. The breccias are related to phreatic explosions triggered by the eruption of a superficial hydrothermal system. Up to 1 m thick sill and a dykelet swarm intrude the breccias. In the southern part of the outcrop there is a plug of melilitolitic composition which intrudes the breccias and deforms them upward. A variety of contact breccias is also scattered around the sill and the plug. In some places, hyaloclastite formed when melt invaded water pockets contained in the encasing rocks under hydrostatic pressure conditions. A thermal aureole, which moves up to 10 m away from the contact, is characterised by cordierite–trydimite association, thus indicating high-temperature (>>1000 °C) contact phenomena.

At Mt. Vulture volcano (Basilicata, Italy) calcite globules (5–150 μm) are hosted by silicate glass pools or veins cross-cutting amphibole-bearing, or more common spinel-bearing mantle xenoliths and xenocrysts. The carbonate globules are rounded or elongated and are composed of a mosaic of 2–20 μm crystals, with varying optical orientation. These features are consistent with formation from a quenched calciocarbonatite melt. Where in contact with carbonate amphibole has reacted to form fassaitic pyroxene. Some of these globules contain liquid/gaseous CO 2 bubbles and sulphide inclusions, and are pierced by quench microphenocrysts of silicate phases. The carbonate composition varies from calcite to Mg-calcite (3.8–5.0 wt.% MgO) both within the carbonate globules and from globule to globule. Trace element contents of the carbonate, determined by LAICPMS, are similar to those of carbonatites worldwide including ΣREE up to 123 ppm. The Sr–Nd isotope ratios of the xenolith carbonate are similar to the extrusive carbonatite and silicate rocks of Mt. Vulture testifying to derivation from the same mantle source. Formation of immiscibile silicate–carbonatite liquids within mantle xenoliths occurred via disequilibrium immiscibility during their exhumation.

Volcanic activity at Mt Vulture lasted throughout the Middle Pleistocene and produced SiO2- undersaturated volcanics. Deposits from the Monte Vulture stratovolcano have been classified into four subsynthems and clustered into the Barile Synthem. In the present investigation, trioctahedral micas from the uppermost units (the Ventaruolo Subsynthem) of the Barile Synthem are considered. The samples are labelled VUT187. The phlogopitic micas were separated from the host rock (an olivinefoidite) and underwent chemical (electron microprobe analysis - EMPA and C-H-N), structural (singlecrystal X-ray diffraction) and spectroscopic (Mössbauer) investigations.The EMPA yielded: MgO (17.62–21.89 wt.%), FeOtot (5.98–9.78 wt.%), TiO2 (1.81–3.92 wt.%) and Al2O3 (14.47–17.98 wt.%), with H2O contents = 2.86 (±0.42) wt.% determined by C-H-N analyses. Mössbauer investigation provided [VI]Fe2+ = 12.6%, [VI]Fe3+ = 87.4%. The chemical and structural data are consistent with the occurrence of Ti-oxy, [VI]M2+ + 2(OH)– ⇋ [VI]Ti4+ + 2O2– + H2, and M3+-oxy substitutions, [VI]M2+ + (OH)– ⇋ [VI]M3+ + O2– + 1/2H2, with M3+ = Fe3+, Al3+. In particular, Fe3+-oxy substitution has affected the Fe2+/Fe3+ ratioin the studied sample. This is probably due to the fact that interaction with underground water or a hydrothermal system may have altered the oxygen fugacity and raised the Fe3+ content of VUT187 phlogopite with respect to magmatic values.

This paper presents a study of melt and fluid inclusions in minerals of an olivine-leucite phonolitic nephelinite bomb from the Monticchio Lake Formation, Vulture. The rock contains 50 vol.% clinopyroxene, 12% leucite, 10% alkali feldspars, 8% hauyne/sodalite, 7.5% nepheline, 4.5% apatite, 3.2% olivine, 2% opaques, 2.6% plagioclase, and

At Oricola (Aquila-Abruzzo, Italy) carbonatite is associated with phonolitic foidite tuff. The Oricola carbonatite contains fresh silicate glass of kamafugitic foidite composition which, compared with carbonate, shows similar trace element patterns but lower concentrations. As a whole, the mineralogy of the Oricola rocks matches that of the neighbouring Grotta del Cervo kamafugitic foidite and carbonatitic foidite and is in the range of the Intramountain Ultralkaline Province (IUP) of melilitites and carbonatites of Italy. The IUP carbonatites and kamafugitic foidites definitely form intra-outcrop conjugate pairs. All these co-eruptive rocks have parallel trace element patterns, namely REE, which implies a dilution–concentration relationship among them but always with higher contents in primary calcite. Based on current textural and compositional criteria, as well as comparable experimental data, we attribute this feature to liquid immiscibility dominant over crystal fractionation at crustal pressure. This relatively late immiscibility phenomenon is superimposed on co-magmatic features shown by inter-outcrop conjugate rock couples. In fact if we consider San Venanzo kamafugite and Polino Ca-carbonatite, or Grotta del Gervo kamafugite and Oricola Ca-carbonatite, we note couple by couple that they are chemical heteromorphs erupted in isolation in different place. The REE distribution is another distinctive feature of these couples and shows a marked crossover at MREE level. A fact we interpret as produced by near mantle-solidus immiscibility. After this early phenomenon the two members of the couple can erupt in a near primary state carrying mantle xenoliths or undergo some evolution including settling out mantle xenoliths and crystals and fractionation and finally exsolve a carbonatitic residuum by immiscibility.

Two distinct occurrences of wollastonite- and melilite-bearing rocks from Ricetto and Colle Fabbri, which are located in the central Italy Apennine Range, are referred to as "paralavas" generated by melting and recrystallization of marly sediments "likely due to coal fires" by Melluso et al. (2003). We submit data demonstrating that these conclusions are incorrect. Ricetto is clearly pyrometamorphic, as described by Capitanio et al. (2001, 2004). Colle Fabbri is clearly an igneous outcrop as described in Stoppa (1988). It is quite different in scale, field relationships, and chemistry, and thus Ricetto is irrelevant to its petrogenesis. The sediment mixing model of Melluso et al. (2003) does not relate to the Colle Fabbri field data. Furthermore, the Ricetto Miocene flysch country-rock and the Colle Fabbri enclosing Pliocene clays were not analyzed by Melluso et al. (2003). A limestone-shale mixing calculation using Sr and Nd isotopic data in Melluso et al. (2003, Tables 3-4) and a 1 4 3Nd/ 1 4 4 Nd ratio of 0.51213 for Apennine shales (op.cit. p. 1297) fails to account for the Colle Fabbri samples, which remain well clear of the hypothetical mixing line. Rocks of mantle origin, including micaceous kimberlites and Western Australia lamproites, plot in the variation field of Colle Fabbri and regionally associated igneous rocks. Colle Fabbri is but one of a series of similar igneous melilite-bearing and carbonatite occurrences that constitute the Intramontane Ultra-alkaline Province of central Italy (IUP), although Colle Fabbri does have unique features, as do other of these occurrences (Stoppa et al. 2003).

The ∽16 Ma Rangwa Caldera Complex, part of the large Kisingiri nephelinite-carbonatite volcano, Homa Bay District, western Kenya (0º34’S; 34º09’E) contains carbonatitic lapilli and ash tuffs, agglomerate and tuffisite, and a number of intrusive calcite carbonatites. A detailed petrographic and electron microprobe study has been performed on 20 fresh samples from the collection at The Natural History Museum, London.Most of the juvenile lapilli and ash particles are either predominantly composed of devitrified silicate glass (now biotite/phlogopite but probably also originally potassic silicate) or calcite carbonatite, which suggests that two molten liquids were erupted simultaneously. Some 10 mm-diameter lapilli contain quench-textured calcite crystals set in devitrified glass. They are interpreted as having crystallized from a molten silicate-carbonate melt at, or very near, the surface.The extrusive carbonate is mostly composed of calcite, consistent with intrusive calcite compositions at Rangwa. Other key minerals are magnetite, two types of mica (magnesian-biotite phenocrysts and phlogopite xenocrysts) and fluorapatite.The pyroclastic rocks contain many calcite carbonatite clasts, and fragments of calcite, aegirine and diopside, fluorapatite, magnetite, plus some phlogopite, titanite, K-feldspar, fenite and glimmerite; ijolite lithics are rare. Thus, there is no evidence for a cognate nephelinitic (ijolitic) or melilitic magma nor evidence for a direct relationship with the nephelinites of the Kisingiri volcano.Two hypotheses are discussed. A rising silicate and K-rich carbonatite liquid may have evolved towards a carbonate-rich K-silicate liquid after crystallization of calcite, phlogopite, apatite and magnetite. Preservation of the the potassic component may be rare, with a more usual scenario being that potassic component separates as fenitizing fluids. The alternative is that the silicate component is remobilized fenite, formed from country rock that was mobilized by supercritical K-rich, fenitizing fluids associated with the carbonatite. Both scenarios require generation of a K-rich carbonatite magma, probably from a carbonated phlogopite-rich metasomatized mantle.

Intrusive calcite-carbonatite ejecta (sovite) in the lowermost tephra layers of the Mt. Vulture alkaline mafic-ultramafic volcano (Upper Pleistocene), is the first intrusive carbonatite sample from southern Europe. The sovite is of coarse granularity and shows some textural and mineralogical layering. It is mainly formed of calcite (up to 3.5 wt.% MgO, and 0.53 wt.% SrO), less dolomite (average 18.2 wt.% MgO, and up to 2.1 wt.% SrO), spinel (60 wt.% Al2O3, 26.5 wt.% MgO, 10.7 wt.% FeO) and olivine (Fo99). Perovskite and apatite have been found only as microlites. Intergranular vugs are scattered throughout the rocks and small composite inclusions occur in calcite.The mineral chemistry, high temperature melt inclusions, overall isotopic compositions, and the REE distribution are consistent with a primary igneous origin. Compared with world average sovite compositions, the Vulture sovite has lower LILE and HFSE but Rb, Sr, Th and U are high. The REE abundance is typical of carbonatites, having an LREE/HREE value of ∼100. The δ13C (−4.8% SMOW) is in the range for mantle-derived carbonatites. The 143Nd/144Nd (0.512648±15) and 87Sr/86Sr (0.705978±10) ratios show close similarity between the sovite and the Vulture alkaline mafic rocks. The sovite ejecta are interpreted as a crystallization product of carbonate ultramafic liquid. In common with many shallow-level carbonatites from other localities, the recrystallization of rather pure Mg-calcite, the presence of dissolution vugs and the depletion of some HFSE and the relatively high δ18O values, suggest that a secondary process, such as hydrothermal leaching, affected the rock.

The Calatrava Volcanic Field (CVF) of Castilla-La Mancha is characterised by numerous monogenetic volcanic centres, that erupted mainly foidites, melilitites and carbonatites (ultra-alkaline rock-association sensu, Le Bas, 1981) carrying abundant mantle xenoliths. At CVF, carbonatites have been described by Bailey et al. (2005) and Stoppa et al. (2011). Along with the volcanic field of Eifel of Germany, Limagne basin of France and Intra-mountain Ultra-alkaline Province (IUP) of Italy, the CVF encompasses the most numerous PlioceneQuaternary extrusive carbonatites in Western Europe in terms of dimension, number and size of volcanoes (Bailey et al., 2005; Bailey et al., 2006). Similar volcanic fields are ToroAkole and Bufumbira in Uganda (Bailey & Collier, 2000), the Avon district in Missouri (Callicoat et al., 2008), Mata da Corda in Brazil (Junqueira-Brod et al., 1999) and West Qinling in Gansu Province, China (Yu et al., 2003). In spite of abundant local studies (Gonzalez Cardenas et al., 2010; Peinado et al., 2009), the CVF has been mostly neglected by the international audience, although Bailey (2005) outlined the need for a long-term research program on CVF. This work focuses on the role of deep CO2 at CVF, which is considered an intrinsic component of carbonatitic mantle magmatism (Hamilton et al., 1979). Previous, studies of CVF volcanoes considered that the hydrovolcanism is a necessary and sufficient condition to explain the CVF volcanological features, and, as a corollary that the carbonate present in the pyroclastic rocks is remobilised limestones (e.g., Lopez-Ruiz et al., 2002). We propose an alternative hypotheses based on CO2 violent exolution and expansion germane to diatremic propagation of ultra-alkaline melts towards the surface and to dry-magmatic origin of the maars (Mattsson & Tripoli, 2011; Stoppa, 1996; Stoppa & Principe, 1998).

Petrography-controlled laser ablation inductively coupled plasma mass spectrometry (LAICPMS) analyses of carbonate in fresh shallow level sub-volcanic Polino monticellite calcio-carbonatite tuffisite have been performed to assess the geochemical differences between fresh igneous, epigenetic carbonates and sedimentary accidental fragments. Igneous calcite has consistently high LREE/HREE ratios (La/Yb N , 15–130) due to high LREE (ΣLREE, 425–1,269 ppm). Secondary calcite cements are characterized by progressively lower and more variable trace element contents, with lower LREE/HREE ratios. A distinguishing geochemical feature is progressively increasing negative Ce anomalies observed through coarse secondary calcite that can be related to the surface environment processes. The limestone accidental fragments in the tuffisite have trace element contents almost two orders of magnitude lower than igneous carbonate and low LREE (ΣLREE

Volcanic activity at Mt. Vulture lasted about 750 ka and produced SiO2-undersaturated volcanic rocks that can be classified as old (similar to 700 ka), intermediate (similar to 600-550 ka), and young (similar to 130 ka). The intermediate deposits consist of pyroclastic falls and flows and lavas with compositions ranging from phonolite to foidite. A recent revision of the stratigraphic setting allowed these deposits to be classified into one synthem (the Barile Synthem) and further subdivided into four subsynthems (Toppo S. Paolo, Rionero, Vulture-S. Michele, and Ventaruolo). In the present investigation, trioctahedral micas from sample VUT191 in the Vulture-S. Michele Subsynthem are considered. The host rock has modal diopside (20.2%), analcime (22.8%), plagioclase (27.8%), hauyne (5%), phlogopite (8.9%), and magnetite (6.3%). The micas were studied using chemical (EPMA, C-H-N, SIMS), structural (SCXRD), and spectroscopic (Moessbauer) methods. EPMA of 36 crystals from thin sections and 6 discrete crystals selected for the structural analysis showed remarkable compositional variability, as follows (in wt%): SiO2 = 33.14-38.01, Al2O3 = 15.56-20.45, MgO = 13.02-20.81, FeOtot = 6.34-14.08, TiO2 = 2.34-6.02, K2O = 6.03-9.48, Na2O = 0.50-0.78, and BaO = 0.89-4.06; all crystals proved to be phlogopite. Elemental C-H-N analyses yielded H2O = 2.86 +/- 0.36 wt%. The water content was also determined by SIMS on two single crystals, labeled VUT191_2 and VUT191_19, which yielded values of 3.81 +/- 0.12 and 1.72 +/- 0.08 wt% H2O, respectively. Moessbauer investigation showed that all the iron in VUT191 mica is octahedral with Fe2+= 25.5% and Fe3+= 74.5%, confirming that Vulture micas are particularly Fe3+-rich, as also found from previous investigations. Structure refinements using anisotropic displacement parameters were performed in space group C2/m and converged at 1.89 Ti-VI(4+) + 2O(2-) + H-2] and M3+-oxy [M-VI(2+) + (OH)(-) M-VI(3+) + O2- + 1/2H(2), with M3+ = Fe3+, Al3+] substitutions. The second group consist of samples in which vacancy-bearing mechanisms, 2 M-VI(2+) Ti-VI(4+) + (VI)square and 3(VI)M(2+) 2(VI)M(3+) + (VI)square occur.

The feasibility of combined current leads with a superconducting extension using high-T/sub c/ superconductors is demonstrated. The performance of systems with heatsink at room temperature or at LN/sub 2/ temperature are compared. In both cases the leads and the busbars are cooled by counterflowing helium gas and the superconducting part can be, depending on T and I, in the superconducting state, in the normal state, or in the current-sharing regime. The improvement obtained by such a system is important notwithstanding the limited current capacity of today high-T/sub c/ superconductors, at least for the LN/sub 2/-cooled system. >

Some of the most diverse igneous rocks found on Earth occur along the length of Italy and in many of the islands in the southeastern Tyrrhenian Sea, all the result of Cenozoic magmatism. Magmas extremely rich in alkalis, particularly potassium, and many undersaturated with respect to silica, were erupted, as well as others of calc-alkalic affinity (see legend in Figure 1). Their origin has been the subject of heated debate, and there is still no general consensus about how they formed. Most attribute them to subduction-related processes (see Beccaluva et al. [2004] for a review); others consider them to be the result of within-plate magmatism [e.g., Vollmer, 1976; Lauecchia and Stoppa, 1996]. Still others consider magmatism the result of a deep, mantle upwelling within a slab window coupled with mixing between isotopically different reservoirs [Gasperini et al., 2002].