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Del Moro, A.
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- PublicationRestrictedSkarn formation at the walls of the 79AD magma chamber of Vesuvius (Italy): Mineralogical and isotopic constraints(2005)
; ; ; ; ; ; ;Fulignati, P.; Dipartimento di Scienze della Terra, Via S. Maria 53, 56126 Pisa, Italy. ;Panichi, C.; Istituto di Geoscienze e Georisorse, CNR, via Moruzzi 1, 56124 Pisa, Italy. ;Sbrana, A.; Dipartimento di Scienze della Terra, Via S. Maria 53, 56126 Pisa, Italy. ;Caliro, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia ;Gioncada, A.; Dipartimento di Scienze della Terra, Via S. Maria 53, 56126 Pisa, Italy. ;Del Moro, A.; Istituto di Geoscienze e Georisorse, CNR, via Moruzzi 1, 56124 Pisa, Italy.; ; ; ; ; This work presents the results of a mineralogical and isotopic (18O, 13C, 87Sr/86Sr) study on xenoliths ejected during the famous 79AD Plinian eruption of Vesuvius. They are considered to be representative of the upper parts of the crystallizing margins of the magma chamber and also of the associated skarn shell. The aim of this study is to describe the thermometamorphic and metasomatic processes which took place at the 79AD magma chamber/wall-rock interface. The results of our research indicate that metasomatism of carbonate wall rocks of the 79AD Vesuvius magma chamber took place due to the infiltration of magmatic fluids, which were exsolved from the peripheral parts of the magma chamber itself. These fluids drive Fe, K, Si, Al and trace elements such as REE, Nb, U, Th, Zr, W, Sb, Pb extracted from the magma into the carbonate host-rocks, thus producing exoskarn. No evidence of later re-equilibrium with low temperature external fluids of meteoric origin was observed. This indicates that only the prograde early stage of skarn formation is recorded in these xenoliths.194 98 - PublicationRestrictedGeodynamic implications of deep mantle upwelling in the source of Tertiary volcanics from the Veneto region (South-Eastern Alps)(2003)
; ; ; ; ; ; ; ;Macera, P.; Dipartimento di Scienze della Terra, Universita’ di Pisa ;Gasperini, D.; Dipartimento di Scienze della Terra, Universita’ di Pisa ;Piromallo, C.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Blichert-Toft, J.; Ecole Normale Superieure, Lyon ;Bosch, D.; Universite ‘‘Montpellier 2", Montpellier ;Del Moro, A.; Istituto di Geoscienze e Georisorse, C.N.R., Pisa ;Martin, S.; Dipartimento di Chimica Fisica Matematica, Universita` Insubria, Como; ; ; ; ; ; Major and trace element and Sr–Nd–Hf–Pb isotopic data for the most primitive Tertiary lavas from the Veneto region (South-Eastern Alps, Italy) show the typical features of HIMU hotspot volcanism, variably diluted by a depleted asthenospheric mantle component (87Sr/86Sri=0.70306–0.70378; "Ndi=+3.9 to +6.8; "Hfi=+6.4 to +8.1, 206Pb/204Pbi=18.786–19.574). P-wave seismic tomography of the mantle below the Veneto region shows the presence of low-velocity anomalies at depth, which is consistent with possible upwellings of plume material. Between the depths of 100–250 km the velocity anomalies are approximately 2–2.5% slower than average, implying a temperature excess of about 220–280 K, in agreement with estimates for other mantle plumes in the world. In this context, the Veneto volcanics may represent the shallow expression of a mantle upflow. The presence of a HIMU-DM component in a collision environment has significant geodynamic implications. Slab detachment and ensuing rise of deep mantle material into the lithospheric gap is proposed to be a viable mechanism of hotspot magmatism in a subduction zone setting.242 23