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Bellatreccia, Fabio
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- PublicationRestrictedTH, U, REE MINERALS IN THE GARA ADJEMAMAYE PERALKALINE GRANITE (CENTRAL HOGGAR, ALGERIA)(2011)
; ; ; ; ; ; ;KAHOUI, Mohammed; USTHB, FSTGAT, Dept of Geology, Bab Ezzouar-El Alia, ALGIERS ;DELLA VENTURA, Giancarlo; Dipartimento Scienze Geologiche,Università di Roma Tre, ROMA ;MAHDJOUB, Yamina; USTHB, FSTGAT, Dept of Geology, Bab Ezzouar-El Alia, ALGIERS ;BELLATRECCIA, Fabio; Dipartimento Scienze Geologiche,Università di Roma Tre, ROMA ;Cavallo, Andrea; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;LOUNI, Chahira; USTHB, FSTGAT, Dept of Geology, Bab Ezzouar-El Alia, ALGIERS; ; ; ; ; The Gara Adjemamaye peralkaline granite outcrops in the Egere-Aleksod terrane (central Hoggar). The main facies is a grey to cream heterogranular rock composed of quartz, mesoperthite, sodi-calcic amphibole, sodic pyroxene, annitic biotite, opaques, Fe-Ti oxides, zircon and abundant (Th, U, REE) bearing minerals. The latter are often finely dispersed in veins crossing the rock, suggesting crystallization due to extensive late-stage remobilization. This work represents a contribution to the crystal-chemistry of these rare minerals and the metasomatic mobility of incompatible elements such as Ti, Zr and REE in igneous environments.171 8 - PublicationOpen AccessCapranicaite: a new mineral from Capranica, Viterbo, Italy(2010-08-21)
; ; ; ; ; ; ;Callegari, A.M.; Dipartimento di scienze della terra, Università di Pavia, Italy ;Boiocchi, M.; Centro Grandi Strumenti, Università di Pavia, Italy ;Bellatreccia, F.; Dipartimento di Scienze Geologiche, Università di Roma Tre, Italy ;Caprilli, E.; Dipartimento di Scienze Geologiche, Università di Roma Tre, Italy ;Medenbach, O.; Institute of Geology, Mineralogy and Geophysics, Ruhr-Universitat Bochum, Germany ;Cavallo, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; ; ; ; ; Capranicaite, ideally KCaNaAl4B4Si2O18, is a new mineral recently approved by the IMA CNMNC (case no. 2009-086) found in the Vico volcanic complex at Capranica, Viterbo, Italy. Capranicaite occurs in miarolitic cavities of a feldspathoid-bearing syenite ejectum probably formed during late-stage metasomatic processes related to volcanic activity. Capranicaite forms small, tabular crystals no longer than 0.1 mm. Crystals are colourless, with a white streak and a vitreous lustre; they are not fluorescent and have a good {001} cleavage. Capranicaite is biaxial (-) with α = 1.495(1), β = 1.543(1), γ = 1.544(1); 2V(obs) = 7.3(2)°. Capranicaite is monoclinic, space group P21/n, a = 4.8507(2), b = 16.6156(6), c = 20.5445(7) Å, β = 90.245(1)°, V = 1655.82(17) Å3, Z = 4. Electron microprobe analysis gives: SiO2 20.70, Al2O3 32.91, B2O3 22.90, K2O 5.36, CaO 11.04, Na2O 4.08, Cs2O 2.20, sum 99.19%. Calculated density is 2.41 gcm-3. The formula unit, calculated on the basis of 18 O, is (K0.69Cs0.10)Ʃ0.79(Ca1.19Na0.80)Ʃ1.99Al3.91B3.99Si2.09O18. Capranicaite is a Cs bearing inosilicate with a new topological arrangement of the 2-periodic Si2O6 single chains. The crystal structure of capranicaite consists of three overlapping layers of polyhedra (A, B, and C) normal to c. The A-layer contains the Si2O6 chains that extend along a. Respect than pyroxene, in capranicaite the Si-tetrahedra are rotated and the Si2O6 groups do not have two apical oxygens pointing towards the same direction. The B-layer is built by isolated AlO4 tetrahedra and BO3 triangles connected to form a continuous sheet of six-fold rings (3Al + 3B). Two B-layers are connected to a single sandwiched A-layer to forms a bi-dimensional B-A-B network. The B-A-B networks contain seven fold cavities not completely populated by K and minor Cs. Adjacent B-A-B bi-dimensional networks are linked together via the C-layer, constituted by isolated octahedra with a mixed (Ca,Na) population. Along c the sequence of layer results C-B-A-B-C-B-A-B-C.255 160 - PublicationRestrictedCapranicaite, (K,square)(Ca,Na)Al(4)B(4)Si(2)O(18): a new inosilicate from Capranica, Italy, with a peculiar topology of the periodic single chain [Si(2)O(6)](2011-02)
; ; ; ; ; ; ;Callegari, A. M.; Univ Pavia, Dipartimento Sci Terra, I-27100 Pavia, Italy ;Boiocchi, M.; Univ Pavia, Ctr Grandi Strumenti, I-27100 Pavia, Italy ;Bellatreccia, F.; Univ Roma Tre, Dipartimento Sci Geol, I-00146 Rome, Italy ;Caprilli, E.; Univ Roma Tre, Dipartimento Sci Geol, I-00146 Rome, Italy ;Medenbach, O.; Ruhr Univ Bochum, Inst Geol Mineral & Geophys, D-44780 Bochum, Germany ;Cavallo, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; ; ; ; ; Capranicaite, ideally (K,square)(Ca,Na)Al(4)B(4)Si(2)O(18), is a new inosilicate mineral from the Vico volcanic complex collected at Capranica, Viterbo Province, Latium, Italy. It occurs in miarolitic cavities of a feldspathoid-bearing syenite ejectum and formed by late-stage metasomatic processes related to the activity of the Vico volcano.187 28 - PublicationOpen AccessMineralogy and textures of riebeckitic asbestos (crocidolite): The role of single versus agglomerated fibres in toxicological experiments(2017-10-15)
; ; ; ; ; ; ; ; ; ; ;; ; ; ; ;; ; ;Asbestos may cause adverse effects, but relationship between mineralogy and texture of fibres versus toxicity is still lacking. Toxicological studies can be interpreted and compared only if quantitative features of fibres are determined. Here, riebeckitic ("crocidolite") amphibole fibres were analysed by XRPD, FTIR, SEM-EDS and EMP-WDS; only crystals with stochiometryA□BNa2C(Fe2+2.5Mg0.5)CFe3+2TSi8O22W(OH)2are present in the starting material used for the experiments. Fibres deposited from solutions of 0.1, 1, 10, 25, 50, 75 and 100mg/L were counted by image analysis using SEM images. At 0.1 and 1mg/L the fibres are well separated, whereas between 1 and 10mg/L they start to agglomerate. In-vitro tests performed on fibres deposited at the same mg/L concentrations show that the toxic potential follows a curvilinear increasing trend with a decreasing rate. Since the range of sizes of single fibres and their mineralogy are constant, this decreasing rate can be only attributed to the increasing amount of agglomerated fibres. Hence, single versus agglomerated fibre population is a factor that cannot be neglected in defining the final adverse effects of asbestos. The analytical protocol proposed here is valuable for any aero-dispersed dust, in polluted environments, as well as in the interpretation of experimental studies.87 36 - PublicationRestrictedApplication of micro-FTIR imaging in the Earth sciences(2010)
; ; ; ; ; ; ; ;Della Ventura, G.; Dipartimento Scienze Geologiche, Università Roma Tre, Roma, Italy ;Bellatreccia, F.; Dipartimento Scienze Geologiche, Università Roma Tre, Roma, Italy ;Marcelli, A.; INFN-Laboratori Nazionali di Frascati, Roma, Italy ;Cestelli Guidi, M.; INFN-Laboratori Nazionali di Frascati, Roma, Italy ;Piccinnini, M.; Porto Conte Ricerche S.r.l, Sassari, Italy ;Cavallo, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Piochi, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia; ; ; ; ; ; In this paper we describe recent applications of micro-infrared imaging in the Earth sciences. We address, in particular, the use of Fourier-transform infrared (FTIR) spectroscopy in characterizing the zoning and speciation of H and C in a variety of geological materials, including microporous minerals, nominally anhydrous volcanic minerals (NAMs), and crystal inclusions. These investigations show that use of the modern techniques of FTIR imaging enables detection of the zoning of volatile species across the studied samples, and possible configuration changes of structurally-bound carbon molecular species (e.g., CO2 vs CO3) during crystal growth. Such features, which are not accessible with other micro-analytical techniques, may provide information about the physicochemical properties which act as constraints in the genesis of the samples, and important information about the evolution of the geological system. Tests performed with focal-plane-array detectors (FPA) show that resolution close to the diffraction limit can be achieved if the amounts of the target molecules in the sample are substantially different. We also point out the possibility of using FTIR imaging for investigations under non-ambient conditions.291 23 - PublicationRestrictedH2O and CO2 in minerals of the hauyne-sodalite group: an FTIR spectroscopy study(2009-07-06)
; ; ; ; ; ;Bellatreccia, F.; Università Roma Tre ;Della Ventura, G.; Università Roma Tre ;Piccinini, M.; Università Roma Tre ;Cavallo, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Brilli, M.; I.N.F.N.; ; ; ; This paper reports an infrared spectroscopic study of a set of sodalite-group minerals. The specimens have been identified using a combination of X-ray diffraction and microchemical analysis. As expected, the Si/Al ratio is ~1; the extra framework cation content is characterized by a well-defined Na -(Ca+K) substitution. The lattice parameters of the studied samples range from sodalite (sample LM11) with a = 8.889(2) A , to hauyne (sample HR3S) with a = 9.1265(2) A. The specimens, having the SO4-- group as a dominant anion, show a clear correlation between the a cell edge and the K content. Single-crystal FTIR spectroscopy shows that hauyne and nosean typically contain enclathrated CO2 molecules,in addition to H2O and minor carbonate, while sodalite is virtually CO2-free. Detailed microspectrometric mappings show a non-homogeneous distribution of volatile constituents across the crystals, which may be related to the presence of fractures in the crystals. Because of such zoning, a relatively wide variation is observed when calibrating extinction coefficients on the basis of a bulk analytical method such as CHN elemental analysis.210 48 - PublicationRestrictedA CO2-rich magma source beneath the Phlegraean Volcanic District (Southern Italy):(2011-06-13)
; ; ; ; ; ; ; ; ;Mormone, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia ;Piochi, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia ;Bellatreccia, F.; Dipartimento di Scienze Geologiche, Università Roma Tre, Roma, Italy ;De Astis, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Moretti, R.; Centro Interdipartimentale di Ricerca in Ingegneria Ambientale (CIRIAM) & Dipartimento di Ingegneria Civile, Seconda Università degli Studi di Napoli, Aversa (CE), Italy ;Della Ventura, G.; Dipartimento di Scienze Geologiche, Università Roma Tre, Roma, Italy ;Cavallo, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Mangiacapra, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia; ; ; ; ; ; ; We present a study of olivine-hosted glass/melt inclusions (MIs) in the most primitive rocks erupted at Procida Island, within the Phlegraean Volcanic District (PVD), Southern Italy. MIs were analyzed by combined Scanning Electron Microscopy coupled with Energy Dispersive X-ray-detectors, Wavelength Dispersive X-rayequipped Electron Microprobe and Fourier Transform Infrared (FT-IR) Spectroscopy; notably, the novel Focal- Plane-Array mode provided high-resolution FT-IR images evidencing the distribution of the C–H–O species across samples. Olivines range in composition from Fo85 to Fo90, do not show chemical zoning and are totally anhydrous. The majority of the MIs are glassy, while only few are completely crystallized. Some MIs, however, show the occurrence of crystal nuclei, i.e., nano- to micro-sized pyroxenes and oxides, and appear as lowcrystallized MIs. The glass of crystal-free and low-crystallized MIs shows K-affinity and a compositional range along the basalt, trachy-basalt, shoshonite, tephrite basanite and phono-tephrite array. H2O and CO2 contents up to 2.69 wt.% and 2653 ppm, respectively, define a major degassing trend with small isobaric deviations. The collected data allow recalculating entrapment pressures from ~350 MPa to b50 MPa and suggest that the magma ascent was dominated by degassing. Crystallization was aminor process, likely also consequent to local CO2-fluxing. Mingling occurred between variable degassed and crystallized magma portions during decompression. The geochemical and isotopic data of Procida glasses and rocks, and the compositional relationship between our MIs and those from slightly more evolved and radiogenic Phlegraean products, indicate that Procida basalts are an adequate parental end-member for the PVD. Our data suggest that a CO2- rich magma source was stored at depths of at least 13–14 km (i.e., 350 MPa) beneath the PVD. Fast ascent of magma batches directly started from this depth shortly before PVD trachy-basaltic to shoshonitic eruptions. Such results have implication on volcanic hazard assessment in the PVD area.923 113 - PublicationOpen AccessFinding of a Cs-rich pharmacosiderite-like mineral: preliminary data(2011-09)
; ; ; ;Petrini, E.; University of ROMA3, Dept. Earth Sciences, L.go S.Leonardo Murialdo 1, 00146 Roma, Italy ;Bellatreccia, F.; University of ROMA3, Dept. Earth Sciences, L.go S.Leonardo Murialdo 1, 00146 Roma, Italy ;Cavallo, Andrea; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; ; In north western Argentina (Jujuy Province), in some volcanic areas, soils and waters are affected by high natural background levels of arsenic (As). Elevated As content can create serious health hazard to the populations settled in the surrounding areas. In this area As is mainly present in the pyroclastic rocks of the volcano Tuzgle (5486 m) whose activity is mainly characterized by emission of andesitic and rhyodacitic products. High concentration levels of As associated with solphur containing Fe and Pb that characterized many deposits along the Andine Cordillera belt248 100