An interview with Giorgio Dall'Aglio

In the fourth interview of the series, Dependence Modeling presents a conversation with Giorgio Dall'Aglio, an Italian mathematician and probabilist who is internationally acknowledged as one of the main contributors to the theory of Distributions with Given Marginals. In addition to describing his career path and his achievements in mathematics and probability, Giorgio Dall'Aglio portraits the several milestone mathematicians he met during his long career. In the following, our questions to Giorgio Dall'Aglio are typeset in bold-face

Geochemical and isotopical variations within the Campanian Comagmatic Province: implications on magma source composition

A spatial variation in chemical and isotopical composition is observed between the volcanoes belonging to the Campanian Comagmatic Province. At a given MgO content, magmas from volcanic islands (Procida and Ischia) are enriched in Ti, Na, depleted in La, Ba, Rb, Sr, Th, K contents, and shows lower LREE/HFSE (e.g., La/Nb = 1-2), lower Sr-Pb isotopic ratios and higher Nd isotopic ratios with respect to magmas from volcanoes located inland (Campi Flegrei and Somma-Vesuvius). The observed compositional variations are explained involving two different mantle sources in the genesis of the magmas erupted in this region: a deeper asthenospheric mantle source, from which the Tyrrhenian magmas also derived and a lithospheric mantle source enriched by slabderived fluids. The contribution of the enriched-lithospheric mantle became more pronounced moving from the Tyrrhenian abyssal plain through the Italian Peninsula where it dominates, likely in response to the thickening of the lithosphere observed under the Peninsula

Geochemical and isotopical variations within the Campanian Comagmatic Province: implications on magma source composition

A spatial variation in chemical and isotopical composition is observed between the volcanoes belonging to the Campanian Comagmatic Province. At a given MgO content, magmas from volcanic islands (Procida and Ischia) are enriched in Ti, Na, depleted in La, Ba, Rb, Sr, Th, K contents, and shows lower LREE/HFSE (e.g., La/Nb = = 1-2), lower Sr-Pb isotopic ratios and higher Nd isotopic ratios with respect to magmas from volcanoes locat- ed inland (Campi Flegrei and Somma-Vesuvius). The observed compositional variations are explained involving two different mantle sources in the genesis of the magmas erupted in this region: a deeper asthenospheric man- tle source, from which the Tyrrhenian magmas also derived and a lithospheric mantle source enriched by slab- derived fluids. The contribution of the enriched-lithospheric mantle became more pronounced moving from the Tyrrhenian abyssal plain through the Italian Peninsula where it dominates, likely in response to the thickening of the lithosphere observed under the Peninsul

Seismic reflection data processing in active volcanic areas: an application to Campi Flegrei and Somma Vesuvius offshore (Southern Italy)

The Campanian volcanism develops near the sea. Therefore, the geophysical study of the marine environment is a key to a better understanding of the tectonic evolution and the origin of volcanism in the area. An abundance of high quality seismic data in the marine sector, where little direct information is available, is critical to the study of Campanian volcanism. This paper concerns the reprocessing of a seismic reflection dataset acquired in Naples Bay and processed during 1973. Even though the overall data quality was high for that time, of course their acquisition technological limits have been overcome by the new processing. Our reprocessing aimed at: 1) reduction of random noise in the data; 2) removal of unwanted coherent events; 3) reduction of spatial aliasing by means of trace interpolation on Commod Shot Point (CSP) gathering; 4) improvement of resolution of the seismic wavelet with spiking deconvolution algorithms and finally 5) reposition of reflectors in their correct locations in the space-TWT domain by means of dip moveout and post-stack time migration. A comparison between the new and old data shows that the new sections are characterized by a much higher S/N ratio. Diffraction hyperbole has been collapsed. Reverberations, ghosts and multiples have been removed or greatly attenuated, especially between the reflectors of interest, allowing us to follow them with more detail and with greater continuity. Furthermore, data resolution has been boosted by the reprocessing, allowing the interpreter to evaluate reflector position and continuity in greater detail. The reinterpretation phase of such lines, that is already in an advanced stage, will therefore allow us to gain new insights into the structural setting of the bay, with the aim of exploring the connection between tectonics and volcanism

The 1998-1999 Pollino (Southern Apennines, Italy) seismic crisis: tomography of a sequence

In 1998-1999 a seismic sequence occurred in the Southern Apennines, after the moderate size (mb=5.0) 9th September 1998 Pollino earthquake. It lasted about 14 months and was clearly localized to the sole north-west area of the main shock epicenter. Its peculiarity consisted in sudden changes of activity from a series of normal faults with Apenninic (NW-SE) trend and transfer, presumably strike slip, faults with Antiapenninic (NE-SW) and E-W trend. The complexity of the behavior and the different orientations of the activated systems suggest that the area acts as a hinge between the NW-SE trending Southern Apennines and the locally N-S trending Calabrian Arc

Evidence of positive tectonic inversion in the north-central sector of the Sicily Channel (Central Mediterranean)

In order to unravel the tectonic evolution of the north-central sector of the Sicily Channel (Central Mediterranean), a seismo-stratigraphic analysis of single- and multi-channel seismic reflection profiles has been carried out. This allowed to identify, between 20 and 50 km offshore the central-southern coast of Sicily, a ~80-km-long deformation belt, characterized by a set of WNW\u2013ESE to NW\u2013SE fault segments showing a poly-phasic activity. Within this belt, we observed: i) Miocene normal faults reactivated during Zanclean\u2013Piacenzian time by dextral strike-slip motion, as a consequence of the Africa\u2013Europe convergence; ii) releasing and restraining bend geometries forming well-developed pull-apart basins and compressive structures. In the central and western sectors of the belt, we identified local transpressional reactivations of Piacenzian time, attested by well-defined compressive features like push-up structures and fault-bend anticlines. The reconstruction of timing and style of tectonic deformation suggest a strike-slip reactivation of inherited normal faults and the local subsequent positive tectonic inversion, often documented along oblique thrust ramps. This pattern represents a key for an improved knowledge of the structural style of foreland fold-and-thrust belts propagating in a preexisting extensional domain. With regard to active tectonics and seismic hazards, recent GPS data and local seismicity events suggest that this deformation process could be still active and accomplished through deep-buried structures; moreover, several normal faults showing moderate displacements have been identified on top of the Madrepore Bank and Malta High, offsetting the Late Quaternary deposits. Finally, inside the northern part of the Gela Basin, multiple slope failures, originated during Pleistocene by the further advancing of the Gela Nappe, reveal tectonically induced potential instability processes

A review of the gravity and magnetic studies in the Tyrrhenian Basin and its volcanic districts

Since the Sixties, the turning point marked by the Plate Tectonics global theory has provided new ideas for the interpretation of the complex geodynamic evolution of the Mediterranean area. The renewed interest that followed gave a strong impulse to the geological and geophysical investigations of the Mediterranean area and, more specifically, of the Tyrrhenian Basin. Therefore, large scale geophysical surveys and oceanographic cruises were carried out until the end of the Eighties to fill the gap of geophysical information existing in the area until then. Afterwards, short scale surveys were prevalent to improve the detail of the information in areas of geodynamic interest. The gathered data sets allowed new models to be formulated, improving the knowledge of the crustal and lithospheric structure of the Tyrrhenian Basin (and surrounding areas) and the reconstruction of its complex geodynamic evolution. In this frame, the contribution of gravity and magnetic investigations has been unquestionable and deserves a wide-ranging review both on large and small scale. The main features of the potential fields resulting from these surveys will be described and the interpretative models suggested by several authors will be summarized

Geothermal resources within carbonate reservoirs in western Sicily (Italy): A review

Abstract Low-to-medium temperature fluid reservoirs hosted in carbonate rocks are some of the most promising and unknown geothermal systems. Western Sicily is considered a key exploration area. This paper illustrate a multidisciplinary and integrated review of the existing geological, geochemical and geophysical data, mainly acquired during oil and gas explorations since the 1950s, specifically re-analyzed for geothermal purposes, has led to understanding the western Sicily geothermal system as a whole, and to reconstructing the modalities and particular features of the deep fluid circulation within the regional reservoir. The data review suggests the presence of wide groundwater flow systems in the reservoir beneath impervious cap rocks. We identified the main recharge areas, reconstructed the temperature distribution at depth, recognized zones of convective geothermal flow, and depicted the main geothermal fluid flow paths within the reservoir. We believe that our reconstruction of geothermal fluid circulation is an example of the general behavior of low-to-medium enthalpy geothermal systems hosted in carbonate units on a regional scale. Due to the recent technological developments of binary plants, these systems have become more profitable, not only for geothermal direct uses but also for power production

Seismotectonic investigations in the inner Cottian Alps (Italian Western Alps): An integrated approach

This work integrates the results of recent geological–structural studies with new seismological data for the inner Cottian Alps to investigate the connection between faults and seismicity. The major post-metamorphic tectonic feature of this sector is represented by a N–S structure, named Lis–Trana Deformation Zone (LTZ). Since the Late Oligocene, this structure accommodated right-lateral (Late Oligocene–Early Miocene) and subsequently normal (post-Early Miocene) displacements. In the Pleistocene, the activity of the LTZ seems to have caused the development of lacustrine basins inside the valleys that drain this sector of Western Alps. The present-day seismicity joins the northern part of the LTZ and, southwards, other minor sub-parallel structures. In transversal cross-section hypocentres highlight steep surfaces. Focal mechanisms calculated along this structure show both extensional and strike–slip solutions, mostly with one roughly N–S striking nodal plane. Both sub-horizontal (with NE–SW to ENE–WSW trend) and steeply dipping P axes with N–S to NW–SE sub-horizontal T axes are observed. Even if clear evidence of Quaternary tectonic activity in the area is missing, on the basis of the available seismological and geological data we propose that in the inner Northern Cottian Alps the present-day seismic activity may be connected to the LTZ, interpreted as minor sub-parallel fault strand of the Canavese Line. The kinematics of this structure is consistent with the focal mechanisms calculated in this area. Structural and seismological data indicate that LTZ is active under a bulk dextral–transtensive regime since the late Oligocene in the inner Cottian Alps, in agreement with the data published for the adjacent domain of the chain.Published1-163.3. Geodinamica e struttura dell'interno della TerraJCR Journalrestricte