Options
D.I.G.A.T., Università G. D’Annunzio, Chieti, Italy
8 results
Now showing 1 - 8 of 8
- PublicationRestrictedGeochemical features of the gas phase extracted from sea-water and rocks of the Marsili seamount (Tyrrhenian sea, Italy): implications for geothermal exploration projects(2011-11-29)
; ; ; ; ; ; ; ; ; ; ; ; ; ;Italiano, Francesco; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Palermo, Palermo, Italia ;Caso, Carlo; D.I.G.A.T., Università G. D’Annunzio, Chieti, Italy ;Cavallo, Andrea; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Favali, Paolo; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Fu, Chen; NTU, National Technical University, Taipei, Taiwan ;Iezzi, Gianluca; D.I.G.A.T., Università G. D’Annunzio, Chieti, Italy ;Martelli, Mauro; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Palermo, Palermo, Italia ;Mollo, Silvio; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Paltrinieri, Diego; Eurobuilding SpA, Servigliano, Italy ;Paonita, Antonio; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Palermo, Palermo, Italia ;Rizzo, Andrea; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Palermo, Palermo, Italia ;Signanini, Patrizio; D.I.G.A.T., Università G. D’Annunzio, Chieti, Italy ;Ventura, Guido; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; ; ; ; ; ; ; ; ; ; ; ; ; ; ;Hilton, David; Scripps Institution, La Jolla, CaliforniaA new target for worldwide geothermal exploration and exploitation is represented by the submarine hydrothermal activity. A geologically young (Upper Pliocene – Pleistocene) area in the Tyrrhenian sea, on the west shore of Italy, provides important heat sources from some seamounts. The heat flow data are characterized by positive anomalies comparable to those of onshore geothermal fields. A geothermal exploration program of the Marsili seamount, the largest volcanic edifice (~30 km in length) in Europe, suggests the presence of a geothermal activity testified by oxy- and hydroxide-deposits predominantly made up of Fe- and Mn-rich sediments, crusts and nodules. Several rock samples of Marsili volcanic activity were collected during dredging and coring projects. These rocks are lavas, pillows and dikes with a calc–alkaline affinity and ranging in composition from basalt to andesite to trachy-andesite. Some tephra layers were also sampled at the top of the volcano showing shoshonitic to latitic bulk compositions and variable amounts of crystals. Importantly, isotopic ratios of noble gases extracted from selected solid samples have provided novel constrains on the Marsili magmatism. In November 2007 and July 2011, water-column studies were carried out aboard of the R/V Urania and Astrea. Isotope analyses of the gases dissolved in water samples collected at the top the Marsili have evidenced that the He/4He isotope ratio, i.e. a clear indicator of hydrothermal input, is in excess with respect to the background and it is also associated with the anomalous behaviour of hydrothermal-derived gases (CO2, CO, CH4). Although some hydrothermal emissions are known to occur offshore the Aeolian subaerial volcanoes, results from our isotope analyses are the first to confirm the hydrothermal activity of Marsili. The highest 3He values were measured over the shallowest part of the seamount, where hydroxide deposits were found. The chemical composition of the dissolved gases clearly shows the presence of CO2 and CH4 over a wide water column depth range. The same anomalies were found in 2007 and 2011, depicting the presence of a persistent plume related to the deep hydrothermal activity of Marsili. A high heat flow (250 mW/m2) is measured at the uppermost portion of the volcano, reaching the maximum value (500 mW/m2) in the central parts. It coincides with gravity and magnetic anomalies, suggesting the presence of magmatic bodies intruding within shallow and thinned crustal levels. Although direct thermal measurements on the Marsili seamount are still lacking, our results give important constraints on the submarine volcanic and hydrothermal activity. Moreover, they support an ongoing project (carried out by Eurobuilding SpA company on the Italian Minister of Economic Development permission) aimed to drill the first offshore geothermal well at the top of the seamount that may potentially represent one of the most abundant energy resources worldwide; this mainly in response to the large amount and virtually infinite recharge of the circulating fluids. To conclude, it is worth noting that besides the scientific information concerning the geothermal activity, the technologies available at the present time will permit on-site geothermal exploitation and 68 production of electric energy (~1 GW) from a seamount located at ~100 km far from the Italian coasts.324 30 - PublicationOpen AccessThe 1930 earthquake and the town of Senigallia (Central Italy): an approach to seismic risk evaluation(1995-11)
; ; ; ; ; ; ;Favali, P.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Frugoni, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Monna, D.; Istituto per le Tecnologie Applicate ai Beni Culturali, CNR, Roma, Italy ;Rainone, M. L.; Istituto per la pianificazione Territoriale, Università di Ancona, Italy ;Signanini, P.; Istituto per la pianificazione Territoriale, Università di Ancona, Italy ;Smriglio, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; ; ; ; ; The town of Senigallia is located on the Adriatic coast of the Marche and Romagna regions (Central Italy), an area affected by offshore seismicity. This city was almost completely destroyed by an earthquake of IX degree intensity on the Mercalli-Cancani-Sieberg scale (MCS) on October 30, 1930. This quake is the most recent and the best documented. In particular, this shock was characterized by strong differences in the damage levels at a scale of hundreds and tens of metres. The geographic position of Senigallia at the mouth of a river and its soil conditions, similar to many other coastal historical and tourist centres in the region, make this earthquake an important case history, useful for a better understanding of the seismic risk of the entire coastal area. This note reports the first results of a study on the possible causes of the different damage levels. The research started with the history and town-planning evolution of Senigallia, then. the regional or local geological characteristics were considered by geological, geotechnical and geophysical investigations.254 816 - PublicationOpen AccessItalian accelerometric archive: geological, geophysical and geotechnical investigations at strong-motion stations(2010)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;Luzi, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia ;Lovati, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia ;D'Alema, E.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia ;Marzorati, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia ;Di Giacomo, D.; GFZ Potsdam ;Hailemikael, S.; UNIROMA1 ;Cardarelli, E.; UNIROMA1 ;Cercato, M.; UNIROMA1 ;Di Filippo, G.; UNIROMA1 ;Milana, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Di Giulio, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Rainone, M.; UNICH ;Torrese, P.; UNICH ;Signanini, P.; UNICH ;Scarascia Mugnozza, G.; UNIROMA1 ;Rivellino, S.; UNIROMA1 ;Gorini, A.; DPC; ; ; ; ; ;; ; ; ; ; ; ; ; ; ; Geological, geophysical and geotechnical investigations, for the characterization of the strong-motion recording sitesmanaged by the ItalianCivil Protection, have been carried out in the framework of the project “Italian strong-motion database in the period 1972–2004”. The project aimed at creating an updated database of strong-motion data acquired in Italy by different institutions in the time span 1972–2004, and at improving the quality of disseminated data. This article illustrates the state of the recording site characterization before the beginning of the project, explains the criteria adopted to select the sites where geophysical/ geotechnical investigation have been performed and describes the results of the promoted field surveys.255 3437 - PublicationOpen AccessThe Marsili Seamount Offshore Geothermal Reservoir: A Big Challenge for an Energy Transition Model(2022)
; ; ; ; ; ; ;; ; ; ;Renewable energies have been the only sources recording a clear increase in total installed capacity, setting a record in new power capacity in 2020, despite the pandemic. The European Union Green Deal represents a strategy towards a sustainable economic model. In this framework, land-based geothermics has seen very limited development; however, offshore geothermics is almost completely absent in the discussion on energy source alternatives, even though it represents a real challenge for energy transition, including the production of green hydrogen. This article discusses an excursus on the activities carried out on offshore geothermal areas worldwide. We focused on the energy potential capacity of the Marsili volcanic seamount located over the bathial plain of the Tyrrhenian Basin, describing the detailed geological, geochemical, and geophysical investigations that have been carried out on that seamount since the 2000s. All the collected data have shown evidence supporting the existence of an exploitable geothermal system in the Marsili seamount consisting of a reservoir of supercritical geothermal fluids of about 100 km3. We discuss and evaluate the actual consistence of the impacts associated with the occurrence of potential risks. We also describe the necessary further steps towards the pilot well. An important breakthrough in the short-medium term that allows for an exit from the predominance of fossil sources may come from the development of energy production derived from offshore high-enthalpy geothermal fields, especially in areas such as the Southern Tyrrhenian Sea. There is a natural clear predisposition for its exploitation combined with a low ecological footprint, which is the target objective of international agreements in the context of a blue economy strategy.59 32 - PublicationOpen AccessThe Marsili Volcanic Seamount (Southern Tyrrhenian Sea): A Potential Offshore Geothermal Resource(2014)
; ; ; ; ; ; ;Italiano, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Palermo, Palermo, Italia ;De Santis, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Favali, P.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Rainone, M. L.; Chieti University ;Rusi, S.; Chieti University ;Signanini, P.; Chieti University; ; ; ; ; Italy has a strong geothermal potential for power generation, although, at present, the only two geothermal fields being exploited are Larderello-Travale/Radicondoli and Mt. Amiata in the Tyrrhenian pre-Apennine volcanic district of Southern Tuscany. A new target for geothermal exploration and exploitation in Italy is represented by the Southern Tyrrhenian submarine volcanic district, a geologically young basin (Upper Pliocene-Pleistocene) characterised by tectonic extension where many seamounts have developed. Heat-flow data from that area show significant anomalies comparable to those of onshore geothermal fields. Fractured basaltic rocks facilitate seawater infiltration and circulation of hot water chemically altered by rock/water interactions, as shown by the widespread presence of hydrothermal deposits. The persistence of active hydrothermal activity is consistently shown by many different sources of evidence, including: heat-flow data, gravity and magnetic anomalies, widespread presence of hydrothermal-derived gases (CO2, CO, CH4), 3He/4He isotopic ratios, as well as broadband OBS/H seismological information, which demonstrates persistence of volcano-tectonic events and High Frequency Tremor (HFT). The Marsili and Tyrrhenian seamounts are thus an important—and likely long-lasting-renewable energy resource. This raises the possibility of future development of the world’s first offshore geothermal power plant.208 305 - PublicationOpen AccessDeep sea explosive eruptions may be not so different from subaerial eruptions(2020-04-21)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; The dynamics of deep sea explosive eruptions, the dispersion of the pyroclasts, and how submarine eruptions differ from the subaerial ones are still poorly known due to the limited access to sea environments. Here, we analyze two ash layers representative of the proximal and distal deposits of two submarine eruptions from a 500 to 800 m deep cones of the Marsili Seamount (Italy). Fall deposits occur at a distance of more than 1.5 km from the vent, while volcanoclastic flows are close to the flanks of the cone. Ash shows textures indicative of poor magma-water interaction and a gas-rich environment. X-ray microtomography data on ash morphology and bubbles, along with gas solubility and ash dispersion models suggest 200-400 m high eruptive columns and a sea current velocity <5 cm/s. In deep sea environments, Strombolian-like eruptions are similar to the subaerial ones provided that a gas cloud occurs around the vent.131 30 - PublicationRestrictedPower-law frequency distribution of H/V spectral ratio of seismic signals: Evidence for a critical crust(2012-03-07)
; ; ;Signanini, P.; Università di Chieti e Pescara “G. D’Annunzio”, Dipartimento Geotecnologie per l’Ambiente e il Territorio, Chieti Scalo, Italy ;De Santis, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; We analyse records from several seismic stations in Central Italy (including some with multiple recording sites) for the statistical properties of spectra of both noise and earthquake signals. The main result is that the power-law scaling of most of the spectral H/V ratio statistical distributions leads to a so-called heavy tail. This is interpreted as a statistical distribution with a fractal dimension of about 2, which is almost certainly caused by a porous percolating medium beneath the stations due to some universal property of the crustal rocks crossed by the elastic waves propagation suggesting that the uppermost crust is in a critical state.187 18 - PublicationRestrictedFirst documented deep submarine explosive eruptions at the Marsili Seamount (Tyrrhenian Sea, Italy): A case of historical volcanism in the Mediterranean Sea(2014)
; ; ; ; ; ; ; ; ; ; ;Iezzi, G.; Uni Chieti ;Caso, C.; Uni Chieti ;Ventura, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Vallefuoco, M.; IAMC Napoli ;Cavallo, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Beherens, H.; Uni Hannover ;Mollo, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia ;Paltrinieri, D.; Eurobuilding ;Signanini, P.; Uni Chieti ;Vetere, F.; Uni Chieti; ; ; ; ; ; ; ; ; The Marsili Seamount (MS) is an about 3200 m high volcanic complex measuring 70 × 30 km with the top at ~500 m b.s.l. MS is interpreted as the ridge of the 2 Ma old Marsili back-arc basin belonging to the Calabrian Arc–Ionian Sea subduction system(Southern Tyrrhenian Sea, Italy). Previous studies indicate that theMS activity developed between 1 and 0.1 Ma through effusions of lava flows. Here, new stratigraphic, textural, geochemical, and 14C geochronological data from a 95 cm long gravity core (COR02) recovered at 839 m bsl in theMS central sector are presented. COR02 contains mud and two tephras consisting of 98 to 100 area% of volcanic ash. The thickness of the upper tephra (TEPH01) is 15 cm, and that of the lower tephra (TEPH02) is 60 cm. The tephras have poor to moderate sorting, loose to partly welded levels, and erosive contacts, which imply a short distance source of the pyroclastics. 14C dating on fossils above and below TEPH01 gives an age of 3 ka BP. Calculations of the sedimentation rates from the mud sediments above and between the tephras suggest that a formation of TEPH02 at 5 ka BP MS ashes has a high-K calcalkaline affinity with 53 wt.% b SiO2 b 68 wt.%, and their composition overlaps that of the MS lava flows. The trace element pattern is consistent with fractional crystallization from a common, OIB-like basalt. The source area of ashes is the central sector of MS and not a subaerial volcano of the Campanian and/or Aeolian Quaternary volcanic districts. Submarine, explosive eruptions occurred atMS in historical times: this is the first evidence of explosive volcanic activity at a significant (500–800 m bsl) water depth in the Mediterranean Sea.MS is still active, the monitoring and an evaluation of the different types of hazards are highly recommended.376 87