http://hdl.handle.net/2122/1 Ricerca nel canale cerca http://www.earth-prints.org/simple-search http://hdl.handle.net/2122/6083 Titolo: Configurazione del PC di comando per stazioni di monitoraggio geochimico di tipo GMS II<br/><br/>Autori: Galli, Gianfranco; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Cinti, Daniele; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Di Stefano, Giuseppe; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Pizzino, Luca; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Pongetti, Francesco; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Quattrocchi, Fedora; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Sciacca, Umberto; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Voltattorni, Nunzia; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia<br/><br/>Abstract: Questo manuale intende fornire le indicazioni necessarie alla corretta configurazione del BIOS edel software del PC dedicato al monitoraggio geochimico con stazioni di tipo GMS II. Per ladescrizione dettagliata di tali stazioni e del relativo software di comando si rimanda ad altrepubblicazioni [1,2]. Si farà riferimento ad un PC equipaggiato con una scheda madre ASUS Mod.CUSI-FX/533/WA/2P-UAY scelta oltre che per ragioni di compattezza anche per alcune suepeculiarità che consentono l’acquisizione dati in assenza di un monitor ed un’opportuna gestioneenergetica per fronteggiare improvvise interruzioni dell’alimentazione elettrica. http://hdl.handle.net/2122/6082 Titolo: Integrated SEED data archive for temporary seismic experiments<br/><br/>Autori: Moretti, Milena; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Govoni, Aladino; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Margheriti, Lucia; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Mandiello, Alfonso Giovanni; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Pintore, Stefano; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Di Stefano, Raffaele; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Chiaraluce, Lauro; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Baccheschi, Paola; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Lauciani, Valentino; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Marcocci, Carlo; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Mazza, Salvatore; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia<br/><br/>Abstract: One of the most valuable results achieved duringthe work on S5 project is the implementation of a new temporarynetwork data management that allows the integration in theNational Data Center together with all other seismological data producedby INGV. This makes all data gathered during temporary experiments immediatelyavailable from the same source and in the same data format (SEED)increasing the availability for processing and analysis. Moreover the data are distributedto the scientific community using the EIDA (European Integrated Data Archivehttp://eida.rm.ingv.it/).The first application has been carried out for the Messina 1908-2008 experiment(WP2.2) http://dpc-s5.rm.ingv.it/en/Database-MessinaFault.html where has beenachieved the complete integration of permanent networks (National Seismic Network,MedNet and Peloritani Local Network), temporary deployments (INGV-CNT and INGVCTmobile networks) and OBS data.All the procedures were used and further improved during the L'Aquila sequence(Task 4) where data was available for processing together with permanentnetwork data as soon as it was gathered from the field giving to thescientific community the opportunity to study the evolution of theseismic sequence with higher density of stations (WP4.2)( h t t p : / / d p c - s 5 . r m . i n g v . i t / e n / D a t a b a s e -AquilaFaultSystem.html). http://hdl.handle.net/2122/6081 Titolo: Seismotectonic of Southern Apennines from recent passive seismic experiments<br/><br/>Autori: Frepoli, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Maggi, C.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Cimini, G. B:; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Marchetti, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Chiappini, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia<br/><br/>Abstract: We used data of local earthquakes collected during two recent passive seismic experiments carried outin southern Italy in order to study the seismotectonic setting of the Lucanian Apennine and the surroundingareas. Based on continuous recordings of the temporary stations we extracted over 15,600waveforms, which were hand-picked along with those recorded by the permanent stations of the Italiannational seismic network obtaining a dense, high-quality dataset of P- and S-arrival times. We examinedthe seismicity occurring in the period 2001–2008 by relocating 566 out of 1047 recorded eventswith magnitudes ML ≥1.5 and computing 162 fault-plane solutions. Earthquakes were relocated using aminimum one-dimensional velocity model previously obtained for the region and a Vp/Vs ratio of 1.83.Background seismicity is concentrated within the upper crust (between 5 and 20km of depth) and it ismostly clustered along the Lucanian Apennine chain axis. A significant feature extracted from this studyrelates to the two E–W trending clusters located in the Potentino and in the Abriola–Pietrapertosa sector(central Lucania region). Hypocentral depths in both clusters are slightly deeper than those observedbeneath the Lucanian Apennine. We suggest that these two seismic features are representative of thetransition from the inner portion of the chain to the external margin characterized by dextral strike-slipkinematics. In the easternmost part of the study area, below the Bradano foredeep and the Apulia foreland,seismicity is generally deeper and more scattered. The sparse seismicity localized in the Sibari Plain,in the offshore area along the northeastern Calabrian coast and in the Taranto Gulf is also investigatedthanks to the new recordings. This seismicity shows hypocenters between 12 and 20km of depth belowthe Sibari Plain and is deeper (foci between 10 and 35km of depth) in the offshore area of the TarantoGulf. 102 well-constrained fault-plane solutions, showing predominantly normal and strike-slip characterwith tensional axes (T-axes) generally NE oriented, were selected for the stress tensor analysis. Weinvestigated stress field orientation inverting focal mechanism belonging to the Lucanian Apennine andthe Pollino Range, both areas characterized by a more concentrated background seismicity. http://hdl.handle.net/2122/6080 Titolo: Eruptive versus non-eruptive behaviour of large calderas: the example of Campi Flegrei caldera (southern Italy)<br/><br/>Autori: Carlino, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia; Somma, R.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia<br/><br/>Abstract: Caldera eruptions are among the most hazardousof natural phenomena. Many calderas around the world areactive and are characterised by recurrent uplift andsubsidence periods due to the dynamics of their magmareservoirs. These periods of unrest are, in some cases,accompanied by eruptions. At Campi Flegrei caldera (CFc),which is an area characterised by very high volcanic risk,the recurrence of this behaviour has stimulated the study ofthe rock rheology around the magma chamber, in order toestimate the likelihood of an eruption. This study considersdifferent scenarios of shallow crustal behaviour, taking intoaccount the earlier models of CFc ground deformation andcaldera eruptions, and including recent geophysical investigationsof the area. A semi-quantitative evaluation of thedifferent factors that lead to magma storage or to itseruption (such as magma chamber size, wall-rock viscosity,temperature, and regional tectonic strain rate) is reportedhere for elastic and viscoelastic conditions. Considering thelarge magmatic sources of the CFc ignimbrite eruptions(400–2,000 km3) and a wall-rock viscosity between 1018and 1020 Pa s, the conditions for eruptive failure aredifficult to attain. Smaller source dimensions (a few cubickilometres) promote the condition for fracture (eruption)rather than for the flow of wall rock. We also analyse theinfluence of the regional extensional stress regime onmagma storage and eruptions, and the thermal stress as apossible source of caldera uplift. The present study alsoemphasises the difficulty of distinguishing eruption andnon-eruption scenarios at CFc, since an unambiguousmodel that accounts for the rock rheology, magma-sourcedimensions and locations and regional stress field influencesis still lacking. http://hdl.handle.net/2122/6079 Titolo: Array analysis and precise source location of deep tremor in Cascadia<br/><br/>Autori: La Rocca, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia; Galluzzo, D.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia; Malone, S.; Department of Earth and Space Sciences, University of Washington, USA; McCausland, W.; Cascade Volcano Observatory, U.S. Geological Survey, Vancouver, USA; Del Pezzo, E.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia<br/><br/>Abstract: We describe a new method to estimate the S‐P time of tremor‐like signals and itsapplication to the nonvolcanic tremor recorded in July 2004 by three dense arrays inCascadia. The cross correlation between vertical and horizontal components indicates thatvery often the high‐amplitude tremor signal contains sequences of P and S wavescharacterized by constant S‐P times (TS‐P) in the range 3.5–7 s. A detailed observation ofthe three component seismograms stacked over the array stations confirms the presence ofP and S wave sequences. The knowledge of the TS‐P poses a strong constrain on thesource‐array distance, which dramatically reduces the uncertainty on source locationswhen used with more traditional array processing techniques. Data were analyzed usingthe zero lag cross‐correlation technique (ZLCC) to estimate the propagation propertiesof the most correlated phases in the wavefield. Detailed polarization analyses werecomputed using the covariance matrix method in the time domain. Polarization parameters,joint with the results of ZLCC, allows for the discrimination between P and S coherentwaves. Results show that the tremor wavefield is composed mostly by shear waves,although a consistent amount of coherent P waves is often observable. The comparison ofthe back azimuth at the three arrays indicate that the source of deep tremor migrates over awide area, and often many independent sources located far from each other are active atthe same time. The tremor source was located by a probabilistic method that uses theresults of ZLCC, given a velocity model. When available, the inclusion of the TS‐P time inthe location procedure strongly reduces the depth range, with a distribution of hypocentersvery near the subduction interface. This result, significantly different compared withprevious less precise locations, makes the Cascadia nonvolcanic tremor more similar to thenonvolcanic tremor recorded in Japan, at least in cases of measurable TS‐P. Thepolarization azimuth aligned with the slow slip direction and the source located on theplate interface indicate that deep tremor and slow slip are two different manifestations of acommon phenomenon related with the subduction dynamics. http://hdl.handle.net/2122/6078 Titolo: Chemical composition of precipitation at Mt. Vesuvius and Vulcano Island, Italy: volcanological and environmental implications<br/><br/>Autori: Madonia, P.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Palermo, Palermo, Italia; Liotta, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Palermo, Palermo, Italia<br/><br/>Abstract: Natural precipitation and water samples frompassive devices were collected at Mt. Vesuvius and VulcanoIsland, Italy, during the period 2004–2006, in order toinvestigate its possible interactions with fumarolic gases.Evidence of chemical reactions between fumarolic fluidsand rain samples before and after its deposition into thesampling devices was found at Vulcano Island. Very lowpH values (down to 2.5) and significant amounts of chlorineand sulfate (up to 22 mEq/l) were measured at samplingpoints located close to the fumarolic field. In contrast,anthropogenic contributions and/or dissolution of aerosols(both maritime and continental) influence the chemistry ofrainwaters at Mt. Vesuvius, which show inter-annualvariations that are highly consistent with those recorded atthe coastal site at Vulcano Island. Chemistry of watersdirectly exposed to fumarolic fluids may then give usefulinformation about its temporal evolution, holding the signalof the ‘‘maximum’’ chemical event occurred in the meanwhile.In addition, the observation of the health status ofvegetation colonizing the immediate surroundings of thefumarolic fields, due to its strong dependence on theinteractions with these fluids, may work as a possiblebiomarker of volcanic activity. http://hdl.handle.net/2122/6077 Titolo: Shear-wave velocity structure at Mt. Etna from inversion of Rayleigh-wave dispersion patterns (2 s < T < 20 s)<br/><br/>Autori: Cristiano, L.; Università degli Studi di Salerno; Petrosino, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia; Saccorotti, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Pisa, Pisa, Italia; Ohrnberger, M.; Institut für Geowissenschaften, Universität Potsdam; Scarpa, R.; Università degli Studi di Salerno<br/><br/>Abstract: In the present study, we investigated the dispersion characteristics ofmedium-to-long period Rayleigh waves (2 s < T < 20 s) using both singlestationtechniques (multiple-filter analysis, and phase-match filter) andmultichannel techniques (horizontal slowness [p] and angular frequency[~] stack, and cross-correlation) to determine the velocity structure forthe Mt. Etna volcano. We applied these techniques to a dataset ofteleseisms, as regional and local earthquakes recorded by two broad-bandseismic arrays installed at Mt. Etna in 2002 and 2005, during two seismicsurveys organized by the Istituto Nazionale di Geofisica e Vulcanologia(INGV), sezione di Napoli. The dispersion curves obtained showed phasevelocities ranging from 1.5 km/s to 4.0 km/s in the frequency band 0.05Hz to 0.45 Hz. We inverted the average phase velocity dispersion curvesusing a non-linear approach, to obtain a set of shear-wave velocity modelswith maximum resolution depths of 25 km to 30 km. Moreover, thepresence of lateral velocity contrasts was checked by dividing the wholearray into seven triangular sub-arrays and inverting the dispersion curvesrelative to each triangle. http://hdl.handle.net/2122/6076 Titolo: Present-day stress in the surroundings of 2009 L’Aquila seismic sequence (Italy)<br/><br/>Autori: Mariucci, M. T.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Montone, P.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Pierdominici, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia<br/><br/>Abstract: The axial zone of the Apenninic belt in central Italy is a tectonically active region affectedby post-orogenic Quaternary extension. The present-day stress field is characterized by aminimum horizontal stress (Shmin) ∼ NE–SW oriented, derived mainly from earthquake focalmechanisms and secondarily from borehole breakouts and fault data. The paper describes thecomputation of the Shmin orientation along two deep boreholes located in the vicinity of thearea hit by the 2009 April 6, Mw 6.3 L’Aquila earthquake. The analysed wells show breakoutzones at a depth range between 1.4 and 4.6 km, giving precious information on a depth intervalusually not investigated by any other data. The results show an Shmin N81 ± 22◦ and N74 ± 10◦ oriented for Varoni 1 and Campotosto 1 wells, respectively. The comparison among thebreakouts, the 2009 seismic sequence, the past seismicity and the Quaternary faults indicatesa small rotation of Shmin orientation from ∼ NE, in the southern, to ∼ ENE in the northernsector of the study area, where the wells are located. These differences are linked both to thenatural variations of data and to the orientation of the main tectonic structures varying fromNW–SE in the Abruzzi region to ∼ N–S moving toward the Umbro-Marchean Apennines. Theidentification of constant Shmin orientations with depth derived from all the examined activestress data, confirms the breakouts as reliable stress indicators also for aseismic areas. http://hdl.handle.net/2122/6075 Titolo: High-Frequency Maximum Observable Shaking Map of Italy from Fault Sources<br/><br/>Autori: Zonno, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia; Basili, R.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Meroni, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia; Musacchio, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia; Mai, P. M.; King Abdullah University of Science and Technology (Thuwal, Saudi Arabia); Valensise, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia<br/><br/>Abstract: This study presents the innovative concept of maximum observable shaking (MOS) maps. Our approach makes use of the improved understanding of the Italian regional tectonic setting and uses composite seismic sources (CSS) taken from an Italian database of individual seismic sources. The CSS are merged with high-frequency scenario calculations of expected maximum shaking in a given area. The results of the MOS evaluation in terms of peak ground acceleration and peak ground velocity have been converted into Mercalli-Cancani-Sieberg intensities and are compared with historical felt intensities from the Italian DBMI04 macroseismic database. http://hdl.handle.net/2122/6074 Titolo: Monitoring and methods to analyse the groundwater quality degradation risk in coastal karstic aquifers (Apulia, Southern Italy)<br/><br/>Autori: Polemio, M.; CNR-IRPI; Dragone, V.; CNR-IRPI; Limoni, P.P.; CNR-IRPI<br/><br/>Abstract: A multi-methodological approach based on monitoring and spatio-temporal analysis of groundwater quality changes is proposed. The presented tools are simple, quick and cost-effective to give service to all sorts of users. The chief purpose of the monitoring network is the detection of the piezometric or potenziometric level in the aquifer. The spatial and multi-temporal analysis of usual chemical and physical data provides both an assessment of the spatial vulnerability of the aquifer to seawater intrusion, defining a salinity threshold between fresh groundwater and brackish groundwater and of the water quality trend in terms of salinity. The evaluation of the salinity trend or of salinity-correlated parameters highlights the effects of groundwater mismanagement. The multiparameter logging provides a rapid groundwater quality classification for each well. The whole approach allows evaluating the effects of current management criteria and designing more appropriate management targets. The Apulian karstic coastal aquifers have been selected as a case study (Southern Italy). Three types of aquifer zones can be distinguished: (1) areas with low vulnerability to seawater intrusion, (2) areas with high vulnerability and (3) areas with variable vulnerability in which the salt degradation largely depends on the ability to manage the well discharge. The water quality degradation caused by seawater intrusion appears to be a combined effect of an anomalous succession of drought periods observed from about 1980 onwards and increased groundwater pumping, particularly during drought periods. A management criterion based on aquifer zones is proposed.