Research Interests:
Research Interests:
ABSTRACT 4), Jochem Kueck (4), Flavia Molisso (2), Joerge Erzinger (5), Christopher R.J. Kilburn (6), Agust Gudmundsson (7), Jean Pierre Burg (8), Alba Zappone (8), and David P. Hill (9) (1) INGV, Osservatorio Vesuviano, Napoli, Italy,... more
ABSTRACT 4), Jochem Kueck (4), Flavia Molisso (2), Joerge Erzinger (5), Christopher R.J. Kilburn (6), Agust Gudmundsson (7), Jean Pierre Burg (8), Alba Zappone (8), and David P. Hill (9) (1) INGV, Osservatorio Vesuviano, Napoli, Italy, (2) CNR-IAMC, Napoli, Italy, (3) CSIC, Barcelona, Spain, (4) ICDP, Potsdam, Germany, (5) GFZ, Potsdam, Germany, (6) UCL, London, UK, (7) Royal Holloway, London, UK, (8) ETH, Zurich, Switzerland, (9) USGS, Menlo Park, USA The Campi Flegrei Deep Drilling Project (CFDDP) entered the operative phase during the second half of 2012, with the pilot hole drilling. The Project was initiated to address two kinds of problems: 1) purely volcanological, to understand in detail the dynamics of the most explosive and yet mostly unknown volcanism on the Earth with the potential to generate global catastrophes, and 2) to mitigate the highest volcanic risk in the World, namely the one associated with the metropolitan area of Naples where more than 3,000,000 people are exposed to extreme risk. The CFDDP Project offers the only direct means to understand the physics driving the on-going ground uplift affecting the area since at least six centuries, through in situ and laboratory measurements of rock rheology and permeability. In particular, direct investigation at depth by drilling is essential for understanding the extent that shallow magma intrusion is involved in the uplift of 15 to 20 m accumulated over the last centuries. Such a high cumulative uplift corresponds to 1-10 km3 of new magma intruded into the system, depending on details of the model used. Such an erupted volume should be conservatively assumed as the worst scenario for a future eruption. This corresponds to a massive eruption, largest than any other one after the caldera-forming Yellow Tuff eruption of 15,000 y BP and not much smaller than that, which would anyway require evacuation of some millions people. An alternative possibility is that the cumulative uplift is mostly due to shallow geothermal perturbations as described in several recent publications. Both possibilities, each with widely differing hazard implications, rely strongly on as yet poorly known conditions at depth beneath the caldera. It is thus crucial to discriminate between these two opposing possibilities in order to clarify the worst scenario for a future eruption and to provide an invaluable tool for civil defence at this densely populated area. This presentation describes preliminary results obtained from CFDDP pilot hole, reaching a final depth of 502 m, which show considerable promise in answering the main open questions. From a volcanological point of view, they enlighten in an unprecedented way the dynamics of the Bagnoli-Fuorigrotta plain, the easternmost part of the caldera and the most densely populated because it includes the city of Naples. Furthermore, they allowed for the first in-situ measurements, at 500 m of depth, of loading stress and fluid-dynamical parameters like permeability, thus already representing a large step forward towards a complete fluid-dynamical interpretation of the ground uplift episodes called 'bradyseism'.
Research Interests:
Research Interests:
Research Interests:
6 Facing Volcanic and Related Hazards in the Neapolitan Area Giovanni Orsi, Sandro de Vita,Mauro A. Di Vito, Roberto Isaia, Rosella Nave, and Grant ... The last period of such activity occurred between 1631 and 1944 (Andronico et al.,... more
6 Facing Volcanic and Related Hazards in the Neapolitan Area Giovanni Orsi, Sandro de Vita,Mauro A. Di Vito, Roberto Isaia, Rosella Nave, and Grant ... The last period of such activity occurred between 1631 and 1944 (Andronico et al., 1995; Cioni et al., 1999; Arrighi et al., 2001 ...
Research Interests:
ABSTRACT The joint application of different seismological techniques for seismic noise analysis, and the results of a volcanological and morphostructural survey, have allowed us to obtain a detailed and well constrained image of the... more
ABSTRACT The joint application of different seismological techniques for seismic noise analysis, and the results of a volcanological and morphostructural survey, have allowed us to obtain a detailed and well constrained image of the shallow crustal structure of the Solfatara volcano (Campi Flegrei caldera, Italy). Horizontal-to-vertical spectral ratios, inversion of surface wave dispersion curves and polarization analysis provided resonance frequencies and peak amplitudes, shear wave velocity profiles and polarization pattern of coherent ambient noise. These results, combined in a unique framework, indicate that the volcanic edifice is characterized by lateral and vertical discontinuities and heterogeneities in terms of shear wave velocity, lithological contrasts and structural setting. The interpretation of the seismological results, with the volcanological and morphostructural constraints, supports the hypothesis that the volcano has been characterized by a complex and intense activity, with the alternation of constructive and destructive phases, during which magmatic and phreatomagmatic explosions built a complex tuff-cone, later reworked by atmospheric agents and altered by hydrothermal activity. The differences in the velocity structure between the central and eastern parts of the crater have been interpreted as resulting from a possible eastward migration of the eruptive vent along the deformational features affecting the area, and to the presence of viscous lava and lithified tuff bodies within the feeding conduits, which are buried under a covering of reworked materials of variable thickness. The observed fault and fracture systems, partially inherited from regional structural setting and exhumed during volcanism and ground deformation episodes also seems to strongly control wave propagation, affecting the noise polarization properties.
Research Interests:
ABSTRACT The joint application of different seismological techniques for seismic noise analysis, and the results of a volcanological and morphostructural survey, have allowed us to obtain a detailed and well constrained image of the... more
ABSTRACT The joint application of different seismological techniques for seismic noise analysis, and the results of a volcanological and morphostructural survey, have allowed us to obtain a detailed and well constrained image of the shallow crustal structure of the Solfatara volcano (Campi Flegrei caldera, Italy). Horizontal-to-vertical spectral ratios, inversion of surface wave dispersion curves and polarization analysis provided resonance frequencies and peak amplitudes, shear wave velocity profiles and polarization pattern of coherent ambient noise. These results, combined in a unique framework, indicate that the volcanic edifice is characterized by lateral and vertical discontinuities and heterogeneities in terms of shear wave velocity, lithological contrasts and structural setting. The interpretation of the seismological results, with the volcanological and morphostructural constraints, supports the hypothesis that the volcano has been characterized by a complex and intense activity, with the alternation of constructive and destructive phases, during which magmatic and phreatomagmatic explosions built a complex tuff-cone, later reworked by atmospheric agents and altered by hydrothermal activity. The differences in the velocity structure between the central and eastern parts of the crater have been interpreted as resulting from a possible eastward migration of the eruptive vent along the deformational features affecting the area, and to the presence of viscous lava and lithified tuff bodies within the feeding conduits, which are buried under a covering of reworked materials of variable thickness. The observed fault and fracture systems, partially inherited from regional structural setting and exhumed during volcanism and ground deformation episodes also seems to strongly control wave propagation, affecting the noise polarization properties.
Research Interests:
6 Facing Volcanic and Related Hazards in the Neapolitan Area Giovanni Orsi, Sandro de Vita,Mauro A. Di Vito, Roberto Isaia, Rosella Nave, and Grant ... The last period of such activity occurred between 1631 and 1944 (Andronico et al.,... more
6 Facing Volcanic and Related Hazards in the Neapolitan Area Giovanni Orsi, Sandro de Vita,Mauro A. Di Vito, Roberto Isaia, Rosella Nave, and Grant ... The last period of such activity occurred between 1631 and 1944 (Andronico et al., 1995; Cioni et al., 1999; Arrighi et al., 2001 ...
Research Interests:
The Campi Flegrei volcano (or Phlegraean Fields), Campania, Italy, generated the largest eruption in Europe in at least 200 ka. Here we summarise the volcanic and human history of Campi Flegrei and discuss the interactions between humans... more
The Campi Flegrei volcano (or Phlegraean Fields), Campania, Italy, generated the largest eruption in Europe in at least 200 ka. Here we summarise the volcanic and human history of Campi Flegrei and discuss the interactions between humans and the environment within the "burning fields" from around 10,000 years until the 1538 CE Monte Nuovo eruption and more recent times. The region's incredibly rich written history documents how the landscape changed both naturally and anthropogenically, with the volcanic system fuelling these considerable natural changes. Humans have exploited the beautiful landscape, accessible resources (e.g. volcanic ash for pulvis puteolana mortar) and natural thermal springs associated with the volcano for millennia, but they have also endured the downsides of living in a volcanically active region-earthquakes, significant ground deformation and landscape altering eruptions. The prehistoric record is detailed, and various archaeological sites indicate that the region was certainly occupied in the last 10,000 years. This history has been reconstructed by identifying archaeological finds in sequences that often contain ash (tephra) layers from some of the numerous volcanic eruptions from Campi Flegrei and the other volcanoes in the region that were active at the time (Vesuvius and Ischia). These tephra layers provide both a relative and absolute chronology and allow the archaeology to be placed on a relatively precise timescale. The records testify that people have inhabited the area even when Campi Flegrei was particularly active. The archaeological sequences and outcrops of pyroclastic material preserve details about the eruption dynamics, buildings from Roman times, impressive craters that now host volcanic lakes and nature reserves, all of which make this region particularly mystic and fascinating, especially when we observe how society continues to live within the active caldera system. The volcanic activity and long record of occupation and use of volcanic resources in the region make it unique and here we outline key aspects of its geoheritage.
Research Interests:
Research Interests:
Stable isotopes were measured in the carbonate and organic matter of palaeosols in the Somma-Vesuvius area, southern Italy in order to test whether they are suitable proxy records for climatic and ecological changes in this area during... more
Stable isotopes were measured in the carbonate and organic matter of palaeosols in the Somma-Vesuvius area, southern Italy in order to test whether they are suitable proxy records for climatic and ecological changes in this area during the past 18000 yr. The ages of the soils span from ca. 18 to ca. 3 kyr BP. Surprisingly, the Last Glacial to
Research Interests:
Research Interests:
The Pomici Principali Tephra (10,3 ka) has been erupted by the highest-magnitude eruption in the Campi Flegrei caldera, one of the most dangerous volcanic areas of the world, during the 12 - 9.5 ka BP epoch of activity. Stratigraphic and... more
The Pomici Principali Tephra (10,3 ka) has been erupted by the highest-magnitude eruption in the Campi Flegrei caldera, one of the most dangerous volcanic areas of the world, during the 12 - 9.5 ka BP epoch of activity. Stratigraphic and stratimetric studies carried out on an area of about 1000 km2 allowed us to reconstruct the whole eruption sequence and
Abstract It is widely accepted that tephra layers represent a fundamental tool in the chronostratrigraphic analysis of sedimentary successions. Particularly, tephrostratigraphy plays a key role in the integrated study of subaerial... more
Abstract It is widely accepted that tephra layers represent a fundamental tool in the chronostratrigraphic analysis of sedimentary successions. Particularly, tephrostratigraphy plays a key role in the integrated study of subaerial environments coupled with ...
Research Interests:
Research Interests:
The Camaldoli hill is the remnant of the north-eastern margin of the Campi Flegrei caldera (CFc), generated by two main collapses related to the Campanian Ignimbrite (CI; 39 ka) and Neapolitan Yellow Tuff (NYT; 15 ka) eruptions. We have... more
The Camaldoli hill is the remnant of the north-eastern margin of the Campi Flegrei caldera (CFc), generated by two main collapses related to the Campanian Ignimbrite (CI; 39 ka) and Neapolitan Yellow Tuff (NYT; 15 ka) eruptions. We have reconstructed its geological, lithological and structural features, and their effects on slope instability. The backbone of the hill includes the remnants of two partially superposed tuff cones, lying between CI and NYT. All these rocks are mantled by a sequence of loose pyroclastic, anthropic and epiclastic deposits, with abrupt thickness and facies variations. Only the uppermost 50-100 cm have been reworked by exogenous agents and anthropic and biological activity. The hill is affected by three fault systems. Its structural setting is mainly due to reactivation of the CI caldera faults until 9.5 ka. Deformation younger than 15 ka is testified by landslide deposits, due to slope instability induced by volcanotectonism, and by a high-angle erosional unconformity, which likely is the response to a base level lowering, generated by faults activation. A detailed stratigraphic analysis of the reworked deposits at the foot of the slopes allowed us to define both depositional mechanisms and sedimentation rate. The results of combined volcanological, and geomorphological and engineering-geological (Calcaterra et al., this session) studies, allowed to constrain and quantify past geological processes and to hypothesise the future evolution of the hill's slopes.
Research Interests:
Research Interests:
The Pomici di Avellino eruption is the Plinian event of Vesuvius with the highest territorial impact. It affected an area densely inhabited by Early Bronze Age human communities and resulted in the long-term abandonment of an extensive... more
The Pomici di Avellino eruption is the Plinian event of Vesuvius with the highest territorial impact. It affected an area densely inhabited by Early Bronze Age human communities and resulted in the long-term abandonment of an extensive zone surrounding the volcano. Traces of human life beneath the eruption products are very common throughout the Campania Region. A systematic review of the available archaeological data, the study of geological and archaeological sequences exposed in excavations , and the reconstruction of the volcanic phenomena affecting single sites has yielded an understanding of local effects and their duration. The archaeological and volcanological analyses have shown that the territory was rapidly abandoned before and during the eruption, with rare post-eruption attempts at resettlement of the same sites inhabited previously. The definition of the distribution and stratigraphy of alluvial deposits in many of the studied sequences leads us to hypothesise that the scarce presence of humans during phases 1 and 2 of the Middle Bronze Age in the wide area affected by the eruption was due to diffuse phenomena of remobilisation of the eruption products, generating long-lasting alluvial processes. These were favoured by the deposition of loose fine pyroclastic material on the slopes of the volcano and the Apennines, and by climatic conditions. A significant resettlement of the territory occurred only hundreds of years after the Pomici di Avellino eruption, during phase 3 of the Middle Bronze Age. This study show the role of volcanic and related phenomena from a Plinian event in the settlement dynamics of a complex territory like Campania.
Research Interests:
Calderas are collapse structures related to the emptying of magmatic reservoirs, often associated with large eruptions from long-lived magmatic systems. Understanding how magma is transferred from a magma reservoir to the surface before... more
Calderas are collapse structures related to the emptying of magmatic reservoirs, often associated with large eruptions from long-lived magmatic systems. Understanding how magma is transferred from a magma reservoir to the surface before eruptions is a major challenge. Here we exploit the historical, archaeological and geological record of Campi Flegrei caldera to estimate the surface deformation preceding the Monte Nuovo eruption and investigate the shallow magma transfer. Our data suggest a progressive magma accumulation from ~1251 to 1536 in a 4.6 ± 0.9 km deep source below the caldera centre, and its transfer, between 1536 and 1538, to a 3.8 ± 0.6 km deep magmatic source ~4 km NW of the caldera centre, below Monte Nuovo; this peripheral source fed the eruption through a shallower source, 0.4 ± 0.3 km deep. This is the first reconstruction of pre-eruptive magma transfer at Campi Flegrei and corroborates the existence of a stationary oblate source, below the caldera centre, that has been feeding lateral eruptions for the last ~5 ka. Our results suggest: 1) repeated emplacement of magma through intrusions below the caldera centre; 2) occasional lateral transfer of magma feeding non-central eruptions within the caldera. Comparison with historical unrest at calderas worldwide suggests that this behavior is common. Defining and understanding the shallow transfer of magma at volcanoes is crucial to forecast eruptions, possibly the ultimate goal of volcanology. This is particularly challenging at felsic calderas experiencing unrest, which typically includes significant changes in seismicity, deformation and degassing rates. In fact, caldera unrest is particularly frequent, affects wide areas and its evidence is often complicated by the presence of a hydrothermal system: as a result, forecasting any eruption and vent-opening sites within an existing caldera is very difficult 1. In historical times only two felsic restless calderas have erupted: Campi Flegrei and Rabaul 2. Campi Flegrei, in the densely inhabited metropolitan area of Naples (Italy), is commonly considered one of the most dangerous active volcanic systems. Campi Flegrei is a ~12 km wide depression hosting two nested calderas formed during the eruptions of the Campanian Ignimbrite (~39 ka) and the Neapolitan Yellow Tuff (~15 ka) (Fig.
Research Interests:
This work arises from the eld observations made during the civil protection emergency period connected to the 2007 Stromboli eruption. We observed changes in the shallow feeding system of the volcano to which we give a volcanological... more
This work arises from the eld observations made during the civil protection emergency period connected to the 2007 Stromboli eruption. We observed changes in the shallow feeding system of the volcano to which we give a volcanological interpretation and the relative implications. Here we describe the processes occurred in the upper feeding system from the end of the 2007 e usive eruption on April 3 until the renewal of the strombolian explosive activity at the summit craters (June 30), interpreted using multidisciplinary data. We used thermal camera data collected both from helicopter and from a xed station at 400 m to retrieve the evolving summit crater activity. These data, compared with seismic signals and published geo-chemical records, allowed us to detail the shifting of the degassing activity within the crater terrace from NE to SW, occurred between April 15 and 25, 2007 prior to the resumption of the strombolian activity. In particular, from mid-April a gradual SW displacement in the maximum apparent temperatures was recorded at the vents within the summit craters, together with a change in the VLP location and con rmed by variations in geochemical indicators (CO2=SO2 plume ratios and CO2 fluxes) from literature. The shallow feeding system experienced a major readjustment after the end of the e ffusive activity, determining variations in the pressure leakage of the source, slowly deepening and shifting toward SW. All these data, together with the framework supplied by previous structural surveys, allowed us to propose that the compaction of debris accumulated in the uppermost conduit by inward crater collapses, occurred in early March, produced the observed anomalies. At Stromboli, major morphology changes, taking place in the following years, were anticipated by these small and apparently minor processes occurred in the upper feeding system. Other studies are relating similar changes to modi cations of the eruptive activity also at other open-conduit volcanoes, so we believe that it may be important to have a constant monitoring of these phenomena in order to better understand their shallow feeding systems.
Research Interests:
Following the geological study performed by Orsi et al. (this session), the main results of a geomorphologic and engineering-geological investigation of the stability conditions of the Camaldoli hill (urban area of Naples) are here... more
Following the geological study performed by Orsi et al. (this session), the main results of a geomorphologic and engineering-geological investigation of the stability conditions of the Camaldoli hill (urban area of Naples) are here presented. The Camaldoli hill, the highest peak of the Phlegraean Fields caldera (452 m asl), is characterized by relief energy of a few hundreds of meters,
Research Interests:
ABSTRACT We present in this work data about a peculiar type of alluvial fans formed exclusively by volcaniclastic material from large explosive eruptions. Each alluvial fan results formed by the superimposition of several sedimentary... more
ABSTRACT We present in this work data about a peculiar type of alluvial fans formed exclusively by volcaniclastic material from large explosive eruptions. Each alluvial fan results formed by the superimposition of several sedimentary bodies, each of them formed by quite homogeneous volcaniclastic material. Lithological analyses allow us to correlate each sedimentary body with the emplacement of pyroclastics from Phlegrean Fields or Somma-Vesuvius. The development of these alluvial fans is controlled by three main factors: area of dispersion of pyroclastics, morphological features of the supplying basin (i.e. mean slopes and area) and climate. Finally, we present an assessment of the minimum time needed for the complete remobilization of pyroclastics of Pomici di Base and Greenish eruptions.