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Papers by Lucia Pappalardo
The evolution of the thermal state of Mt.Vesuvius after the 1631 eruption (during an almost conti... more The evolution of the thermal state of Mt.Vesuvius after the 1631 eruption (during an almost continuous eruptive cycle until the last episode in 1944) and in the subsequent quiescent period until present, has been investigated. An axysimmetric,two-dimensional,finite-element model accounting for conduction and phase changes in an homogenous, isotropic medium endowed with realistic physical constants calculated on the basis of the
General Relativity and Gravitation, 2010
We review the main results, giving some new analyses and insight, obtained in recent times about ... more We review the main results, giving some new analyses and insight, obtained in recent times about the structure, present dynamics and hazard evaluation at Somma-Vesuvius volcanic complex. We present a global review and interpretation of structural features, both at local and regional scale, constrained both by seismic and petrological data. The local structure of Somma-Vesuvius is reviewed in three depth ranges, shallow, intermediate and deep. The shallow velocity structure is inferred by the joint inversion of shot and local earthquake arrival time data. The main feature pointed out at shallow depth is a high velocity anomaly at the crater axis, extending down to about 5 Km of depth. Such an anomaly, first observed at Vesuvius, seems to be common to many other volcanoes. It can be interpreted in terms of the presence of solidified residual magma in the shallow conduits, accumulated in last eruptive cycles. The local seismicity is strongly clustered around this anomaly, due to the focusing effect of the rigidity contrast. The seismic occurrence appears as a result of the superposition of a background level, mainly due to gravitational instability of the Vesuvius cone, and of intense activity episodes, which possibly reflect episodic internal activity. Two main zones of magma accumulation in the upper crust are evidenced by the joint interpretation of seismic and petrological data. The first one, located in the depth range 4-6 km, is mainly constrained by the crystallisation depth of phonolitic magmas which fed Plinian and sub-Plinian eruptions; the second one, around 11-15 km of depth, is mainly constrained by reflected-converted seismic waves, and in agreement with crystallization depths inferred for the moderate eruptions. The study of the deep structure, performed by regional tomography with teleseisms, further points out magma roots at higher depths (15-30 km). An additional result for the deep structure, studied at regional scale and very important for geodynamic interpretations of the Tyrrhenian volcanisms, has been the evidence for a subducting slab under the Apennines, in an area where previous models hypothesised a slab window. New original studies of crystal growth (phenocrystals and microlites) on the eruptive products allow to infer typical times of magma rising from such reservoirs, which appear very low, on the order of minutes to tens of minutes. Static deformation at this volcano, in the last 30 years, has been detected by the joint use of levelling, GPS and DifSAR techniques. It indicates subsidence, very concentrated in the crater area and in a narrow strip all around the volcanic edifice, with maximum rates less than 0.01 m/year. Static deformation in the crater area appears in agreement with the mechanism of gravitational instability generating local volcano-tectonic seismicity, while the peculiar pattern around the volcanic edifice is probably due to the combination of extensional stress and volcanic loading, generating a ring normal fault-like structure. While the key results about structure and dynamics help to define pre-eruptive scenarios, a new probabilistic procedure to combine volcanological data and computer simulations has been used, in this paper, to build hazard maps giving the probability, at each location in the area, to be hit by a pyroclastic flow or to experience a destructive fall-out deposit. The review and new results of this work give then the first complete picture of the state of the art in our knowledge about Somma-Vesuvius volcano.
Agu Spring Meeting Abstracts, May 1, 2005
ABSTRACT
AIP Conference Proceedings, 2000
J Mol Biol, 1998
An NMR-based structure is presented for a 20 mer hairpin model of the SL3 stem-loop from the HIV-... more An NMR-based structure is presented for a 20 mer hairpin model of the SL3 stem-loop from the HIV-1 packaging signal. The stem has an A-family structure. However, the GGAG tetraloop appears to be flexible with the second (G10) and fourth (G12) bases extruded from the normal stacking arrangement. The A-base (A11) occupies a cavity large enough for it to jump rapidly between stacking upon G9 (in the loop) and G13 (from the base-pair adjacent to the loop). The H-bonding loci of G10, A11, and G12 are unoccupied in the free RNA structure. The loop should be easily adaptable to binding by the HIV-1 nucleocapsid protein or loop receptors.
Differentiation mechanisms and timescale controlling over-pressuring and opening of magma chamber... more Differentiation mechanisms and timescale controlling over-pressuring and opening of magma chambers are crucial issues for volcanic risk evaluation, particularly in densely populated areas. Neapolitan high-risk volcanoes produced tens of eruptions with VEI ranging between 1 and 7. Here we analyze the chemical composition of minerals and glass-matrixes of most Somma-Vesuvius and Campi Flegrei explosive and effusive eruptions in order to
Probabilistic approaches based on available volcanological data from real eruptions of Campi Fleg... more Probabilistic approaches based on available volcanological data from real eruptions of Campi Flegrei and Somma-Vesuvius, are assembled in a comprehensive assessment of volcanic hazards at the Neapolitan area. This allows to compare the volcanic hazards related to the different types of events, which can be used for evaluating the conditional probability of flows and falls hazard in case of a
... Phone: +39 0816108444, Fax: + 39 0816108351 E-mail: lucia.pappalardo@ov.ingv.it(lucia.pappala... more ... Phone: +39 0816108444, Fax: + 39 0816108351 E-mail: lucia.pappalardo@ov.ingv.it(lucia.pappalardo@ov.ingv.it)), AB(Istituto Nazionale di Geofisica e Vulcanologia, sezione di Napoli Osservatorio Vesuviano, Via Diocleziano, 328, 80124 Napoli, Italy. ...
The evolution of the thermal state of Mt.Vesuvius after the 1631 eruption (during an almost conti... more The evolution of the thermal state of Mt.Vesuvius after the 1631 eruption (during an almost continuous eruptive cycle until the last episode in 1944) and in the subsequent quiescent period until present, has been investigated. An axysimmetric,two-dimensional,finite-element model accounting for conduction and phase changes in an homogenous, isotropic medium endowed with realistic physical constants calculated on the basis of the
General Relativity and Gravitation, 2010
We review the main results, giving some new analyses and insight, obtained in recent times about ... more We review the main results, giving some new analyses and insight, obtained in recent times about the structure, present dynamics and hazard evaluation at Somma-Vesuvius volcanic complex. We present a global review and interpretation of structural features, both at local and regional scale, constrained both by seismic and petrological data. The local structure of Somma-Vesuvius is reviewed in three depth ranges, shallow, intermediate and deep. The shallow velocity structure is inferred by the joint inversion of shot and local earthquake arrival time data. The main feature pointed out at shallow depth is a high velocity anomaly at the crater axis, extending down to about 5 Km of depth. Such an anomaly, first observed at Vesuvius, seems to be common to many other volcanoes. It can be interpreted in terms of the presence of solidified residual magma in the shallow conduits, accumulated in last eruptive cycles. The local seismicity is strongly clustered around this anomaly, due to the focusing effect of the rigidity contrast. The seismic occurrence appears as a result of the superposition of a background level, mainly due to gravitational instability of the Vesuvius cone, and of intense activity episodes, which possibly reflect episodic internal activity. Two main zones of magma accumulation in the upper crust are evidenced by the joint interpretation of seismic and petrological data. The first one, located in the depth range 4-6 km, is mainly constrained by the crystallisation depth of phonolitic magmas which fed Plinian and sub-Plinian eruptions; the second one, around 11-15 km of depth, is mainly constrained by reflected-converted seismic waves, and in agreement with crystallization depths inferred for the moderate eruptions. The study of the deep structure, performed by regional tomography with teleseisms, further points out magma roots at higher depths (15-30 km). An additional result for the deep structure, studied at regional scale and very important for geodynamic interpretations of the Tyrrhenian volcanisms, has been the evidence for a subducting slab under the Apennines, in an area where previous models hypothesised a slab window. New original studies of crystal growth (phenocrystals and microlites) on the eruptive products allow to infer typical times of magma rising from such reservoirs, which appear very low, on the order of minutes to tens of minutes. Static deformation at this volcano, in the last 30 years, has been detected by the joint use of levelling, GPS and DifSAR techniques. It indicates subsidence, very concentrated in the crater area and in a narrow strip all around the volcanic edifice, with maximum rates less than 0.01 m/year. Static deformation in the crater area appears in agreement with the mechanism of gravitational instability generating local volcano-tectonic seismicity, while the peculiar pattern around the volcanic edifice is probably due to the combination of extensional stress and volcanic loading, generating a ring normal fault-like structure. While the key results about structure and dynamics help to define pre-eruptive scenarios, a new probabilistic procedure to combine volcanological data and computer simulations has been used, in this paper, to build hazard maps giving the probability, at each location in the area, to be hit by a pyroclastic flow or to experience a destructive fall-out deposit. The review and new results of this work give then the first complete picture of the state of the art in our knowledge about Somma-Vesuvius volcano.
Agu Spring Meeting Abstracts, May 1, 2005
ABSTRACT
AIP Conference Proceedings, 2000
J Mol Biol, 1998
An NMR-based structure is presented for a 20 mer hairpin model of the SL3 stem-loop from the HIV-... more An NMR-based structure is presented for a 20 mer hairpin model of the SL3 stem-loop from the HIV-1 packaging signal. The stem has an A-family structure. However, the GGAG tetraloop appears to be flexible with the second (G10) and fourth (G12) bases extruded from the normal stacking arrangement. The A-base (A11) occupies a cavity large enough for it to jump rapidly between stacking upon G9 (in the loop) and G13 (from the base-pair adjacent to the loop). The H-bonding loci of G10, A11, and G12 are unoccupied in the free RNA structure. The loop should be easily adaptable to binding by the HIV-1 nucleocapsid protein or loop receptors.
Differentiation mechanisms and timescale controlling over-pressuring and opening of magma chamber... more Differentiation mechanisms and timescale controlling over-pressuring and opening of magma chambers are crucial issues for volcanic risk evaluation, particularly in densely populated areas. Neapolitan high-risk volcanoes produced tens of eruptions with VEI ranging between 1 and 7. Here we analyze the chemical composition of minerals and glass-matrixes of most Somma-Vesuvius and Campi Flegrei explosive and effusive eruptions in order to
Probabilistic approaches based on available volcanological data from real eruptions of Campi Fleg... more Probabilistic approaches based on available volcanological data from real eruptions of Campi Flegrei and Somma-Vesuvius, are assembled in a comprehensive assessment of volcanic hazards at the Neapolitan area. This allows to compare the volcanic hazards related to the different types of events, which can be used for evaluating the conditional probability of flows and falls hazard in case of a
... Phone: +39 0816108444, Fax: + 39 0816108351 E-mail: lucia.pappalardo@ov.ingv.it(lucia.pappala... more ... Phone: +39 0816108444, Fax: + 39 0816108351 E-mail: lucia.pappalardo@ov.ingv.it(lucia.pappalardo@ov.ingv.it)), AB(Istituto Nazionale di Geofisica e Vulcanologia, sezione di Napoli Osservatorio Vesuviano, Via Diocleziano, 328, 80124 Napoli, Italy. ...