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Giammanco, Salvatore
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Giammanco, Salvatore
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salvatore.giammanco@ingv.it
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- PublicationRestrictedA multidisciplinary approach to detect active pathways for magma migration and eruption at Mt. Etna (Sicily, Italy) before the 2001 and 2002-03 eruptions(2004-08-30)
; ; ; ; ;Alparone, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Andronico, D.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Giammanco, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Lodato, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; ; ; Two strong flank eruptions occurred in July–August 2001 and from late October 2002 to late January 2003 at Mt. Etna volcano. The two eruptions mainly involved the upper southern flank of the volcano, a particularly active area during the last 30 years, damaging several tourist facilities and threatening some villages. The composite eruptive activity on the upper southern flank of Mt. Etna during 2001–2003 has confirmed “a posteriori” the results of a multidisciplinary study, started well before its occurrence by combining geological, seismic and geochemical data gathered in this part of the volcano. We were able, in fact, to highlight fractured zones likely to be re-activated in the near future in this area, where the largest majority of eruptive fissures in the recent past opened along N120° to N180° ranging directions. The spatial distribution of earthquake epicentres during the period June 30th 2000–June 30th 2001 showed the greatest frequency in a sector compatible with both the direction of the main fissures of the pre-2001 period and that of the 2001 and 2002 lateral eruptions. Soil CO2 and soil temperature surveys carried out in the studied area during the last 3 years have revealed anomalous release of magmatic fluids (mainly CO2 and water vapour) along some NNW–SSE-trending volcano-tectonic structures of the area even during inter-eruptive periods, indicating persistent convective hydrothermal systems at shallow depth connected with the main feeder conduits of Etna. The temporal changes in both seismic and geochemical data from June 30th, 2000 to June 30th, 2001 were compared with the evolution of volcanic activity. The comparison allowed to recognize at least two sequences of anomalous signals (August to December 2000 and April to June 2001), likely related to episodes of step-like magma ascent towards the surface, as indicated by the following eruptive episodes. The N120° to N180° structural directions are in accord with one of the main structural lines affecting eastern Sicily; they would be important pathways for magma uprise to the surface that will keep on feeding the eruptive activity of Etna in the near future. This study also pointed out the high instability of the southern slope of Etna, a sector where the potential hazard by lava flow invasion will remain high also in the near future.597 248 - PublicationOpen AccessCan Directional Resonances Be Used to Map Intensely Deformed Fault Zones of Mt. Etna Volcano ?(2009-04-08)
; ; ; ; ; ; ; ; ; ;Cara, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Di Giulio, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Giammanco, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Lombardo, G.; Università di Catania ;Milana, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Neri, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Rigano, R.; Università di Catania ;Rovelli, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Voltattorni, N.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; ; ; ; ; ; ; ; Mt. Etna is characterized by flank instability of the eastern to south-western portions of the volcanic edifice, producing down-slope movements with rates up to several decimeters in a month during eruptive events of the 2002-2003 activity. The unstable sector is bounded to the North by a E-W transtensive fault (the Pernicana fault system), extending from the NE Rift to the coastline of the Ionian Sea for a length of >18 km. The western portion of the Pernicana fault system (close to Piano Pernicana area) is characterized by the most intense deformation. In this area we have performed volcanic tremor measurements on a dense grid along and across the fault zone. Ambient vibration measurements are also performed along a second fault (Tremestieri fault) which confines the slip of the eastern flank to the south-east. The analysis using both microtremors and local earthquakes recorded in these faults shows persistent polarization of ground motion. Horizontal-to-vertical spectral ratios (HVSR) show large directional resonances of horizontal components within the damaged fault zones. The resonance occurs around 1Hz at Piano Pernicana, and around 4 Hz in the Tremestieri fault zone. The resonance amplitude in the HVSRs seems to be fairly well correlated to soil gas anomalous concentrations (in particular, radon and CO2 both considered tracer gases of major crustal discontinuity) in the two fault zones, suggesting that both the effects are linked to local fracturing conditions. According to previous results on velocity anisotropy in the shallow crust, we believe that a role on polarization could be played by stress-induced anisotropy and micro-fracture orientation in the near-surface lavas. The occurrence of directional resonances, if confirmed in other faults, can be a powerful tool to map buried damaged fault zones on the Mt. Etna volcano.233 192 - PublicationOpen AccessDiffuse and Visible Emission of CO2 from Etna Volcano, Italy(2010-05-31)
; ; ; ; ; ; ; ;Melian, Gladys; Environmental Research Division, ITER, Tenerife/Spain ;Hernandez, Pedro; Environmental Research Division, ITER, Tenerife/Spain ;Sortino, Francesco; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Palermo, Palermo, Italia ;Giammanco, Salvatore; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Barrancos, José; Environmental Research Division, ITER, Tenerife/Spain ;Lopez, Manuela; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Perez, Nemesio M.; Environmental Research Division, ITER, Tenerife/Spain; ; ; ; ; ; This work reports the first estimation of total CO2 emission to the atmosphere (visible and non-visible) from Etna volcano, Sicily, by means of direct methods. Until present, only direct measurements of the CO2 emitted by the volcanic plume of Etna had been performed, and not data of direct soil CO2 efflux from surface environment of this volcano were available. To estimate the total CO2 emission, 4075 soil CO2 efflux measurements were performed by means of the accumulation chamber method in October-November 2008. Most of the study area showed background levels of soil CO2 efflux (0.53 g·m-2·d-1), while peak values (>1725 g·m-2·d-1) were mainly identified inside the summit craters and at Torre del Filosofo area. Other zones with relatively high CO2 efflux values were identified at Paternó, Zafferana Etnea and Trecastagni-Viagrande. The total output of CO2 diffuse emission from the study area (973 km2) was computed in 20320 t·d-1, where 1671 t·d-1, about 8.3% of CO2 diffuse emission, was emitted by an area of 87 km2 which includes the summit craters and Torre del Filosofo. To evaluate the visible/diffuse CO2 emission ratio, plume CO2 emission rate was estimated by multiplying SO2 emission rate times observed CO2/SO2 plume ratio following the methodology described by Shinohara (2005). Total CO2 visible emission was estimated about 31.5 kt·d-1, value is in the range reported for Etna volcano (0.9-67.5 kt·d-1; Aiuppa et al., 2006). The total output of CO2 diffuse emission represents 39% of the total CO2 emission from Etna volcano to the atmosphere. These results agree with the observations of Allard et al. (1991), who reported that diffuse and visible CO2 emissions were in the same order of magnitude. This study demonstrates the importance of measuring diffuse CO2 emissions from active volcanoes like Mt. Etna in order to have a better approach on the global estimate of CO2 emission to the atmosphere from subaerial volcanoes316 279 - PublicationOpen AccessAssessment of the Geochemical Potential in a Complex Tectonic Environment of South-East Sicily: New Insights From Hydrochemical Data(2019-04-26)
; ; ; ; ; ; ; We analyzed a large dataset (143 water sampling sites, 22 variables) of chemical parameters in local groundwaters from the south-east sector of Sicily, namely the Hyblean plateau, in order to set an original evaluation of its geothermal potential using applied geochemistry. The area was affected by volcanism until about 1.4 Ma. Today, though no active volcanism occurs, it is site of surface gas manifestations of focused degassing to which a mantle source has been attributed. We identified and thence selected the most promising sites (water springs and wells) based both on their main geochemical characteristics and on their calculated equilibrium temperature (resulting in the range between 50 and 140 C).We then applied Principal Component Analysis (PCA) to this restricted dataset and we were able to discriminate between different sources of solutes, both natural and anthropogenic. Finally, we mapped the factor scores obtained from PCA and we focused on those likely related with geothermal conditions in order to highlight the areas with the highest geothermal potential.900 29 - PublicationOpen AccessImaging the Salinelle Mud Volcanoes (Sicily, Italy) using integrated geophysical and geochemical surveys(2020)
; ; ; ; ; ; ; ; ; Geochemical and geophysical prospecting methods (including measurements of soil heat flux and soil CO2 flux, gravimetry, self-potential and geomagnetism) are used to produce an integrated data set aimed at imaging the migration of fluids in the sub-surface at the Salinelle mud volcanoes, located on the lower southwestern flank of Mt Etna (Sicily, Italy). This area was affected by magmatic eruptions from local volcanic centers between about 48 and 27 ka. Today, only pseudo-volcanic phenomena due to over-pressured multiphase pore fluids there occur. Carbon dioxide of magmatic origin, mixed with biogenic hydrocarbons, warm hypersaline waters and mud, are constantly released at the surface through the main conduits of mud volcanoes, whose activity is characterized by alternation of mild gas bubbling periods and strong paroxysmal phases. The latter produce violent gas eruptions that eject warm water (T ≈ 50° C) to a height up to about 1 m. Surface distribution of the geophysical and geochemical parameters have been investigated to detect the main pathways through which fluids move toward the shallow crust. Integration of geochemical, geophysical and geological maps allowed for the tracing of the fluid flow in the shallowest (a few tens of meters below the surface) part of the local hydrothermal system. Our results showed that the rising of fluids from a deep reservoir is controlled by the main structural and geological features of the area and their temporal and spatial evolution depends on pressure conditions inside the hydrothermal system.1063 55 - PublicationOpen AccessRapporto geochimica eruzione Etna (09 Settembre 2006)(2006)
; ; ;Giammanco, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Consoli, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; 100 101 - PublicationRestrictedMeasurements of 220Rn and 222Rn and CO2 emissions in soil and fumarole gases on Mt. Etna volcano (Italy): Implications for gas transport and shallow ground fracture(2007-10-04)
; ; ; ;Giammanco, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Sims, K. W. W. ;Neri, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; ;Measurements of 220Rn and 222Rn activity and of CO2 flux in soil and fumaroles were carried out on Mount Etna volcano in 2005–2006, both in its summit area and along active faults on its flanks. We observe an empirical relationship between (220Rn/222Rn) and CO2 efflux. The higher the flux of CO2, the lower the ratio between 220Rn and 222Rn. Deep sources of gas are characterized by high 222Rn activity and high CO2 efflux, whereas shallow sources are indicated by high 220Rn activity and relatively low CO2 efflux. Excess 220Rn highlights sites of ongoing shallow rock fracturing that could be affected by collapse, as in the case of the rim of an active vent. Depletion both in 220Rn and in CO2 seems to be representative of residual degassing along recently active eruptive vents.123 16 - PublicationOpen AccessMonitoraggio vulcanologico dell’Etna Aggiornamento alle ore 15:00 GMT (17:00 locali) del 2 maggio 2008(2008-05-02)
; Giammanco, S.218 64 - PublicationOpen AccessA multidisciplinary study on gas emission and volcanic tremor characteristics of Mt. Etna(2011-12-05)
; ; ; ; ; ; ; ;Behncke, B.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Falsaperla, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Giammanco, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Langer, H.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Neri, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Pecora, E.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Salerno, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; ; ; ; ; ; A multidisciplinary study on gas emission and volcanic tremor characteristics of Mt. Etna B. Behncke, S. Falsaperla, S. Giammanco, H. Langer, M. Neri, E. Pecora, G. Salerno Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Catania, Osservatorio Etneo,P.zza Roma 2, 95125, Catania, Italy The 2008-2009 eruption of Mt. Etna was heralded by episodes of paroxysmal summit activity, with strong Strombolian activity and spectacular lava fountains and flows, starting from spring 2007. In this study, we present analyses of a three-month period (from February to April, 2007) which led to the first paroxysm. In doing so, we merge volcanic tremor data and gas measurements of SO2 and Radon. This multidisciplinary study allows characterizing a stage during which the volcano feeder was affected by fluid recharge, producing to repeated episodes of temporary increases in volcanic tremor amplitude, without any visible phenomenon at the surface. We investigate on these spurious changes in tremor characteristics and their relationship to gas emission. Ruling out other exogenous sources, we hypothesize that certain changes represented aborted eruptions, where the magma failed to reach the surface.225 114 - PublicationOpen AccessEruzione dell’Etna Sopralluogo sul terreno del 4 luglio 2008 Aggiornamento alle ore 19:00 (tempi espressi in ora locale)(2008-07-04)
; ;Giammanco, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia131 70