Valentina Bruno

A comprehensive interpretative model of slow slip events on Mt. Etna's eastern flank

Starting off from a review of previous literature on kinematic models of the unstable eastern flank of Mt. Etna, we propose a new model. The model is based on our analysis of a large quantity of multidisciplinary data deriving from an extensive and diverse network of INGV monitoring devices deployed along the slopes of the volcano. Our analysis had a twofold objective: first, investigating the origin of the recently observed slow-slip events on the eastern flank of Mt. Etna; and second, defining a general kinematic model for the instability of this area of the volcano. To this end, we investigated the 2008–2013 period using data collected from different geochemical, geodetic, and seismic networks, integrated with the tectonic and geologic features of the volcano and including the volcanic activity during the observation period. The complex correlations between the large quantities of multidisciplinary data have given us the opportunity to infer, as outlined in this work, that the fluids of volcanic origin and their interrelationship with aquifers, tectonic and morphological features play a dominant role in the large scale instability of the eastern flank of Mt. Etna. Furthermore, we suggest that changes in the strain distribution due to volcanic inflation/deflation cycles are closely connected to changes in shallow depth fluid circulation. Finally, we propose a general framework for both the short and long term modeling of the large flank displacements observed.

Dome-like behaviour at Mt. Etna: The case of the 28 December 2014 South East Crater paroxysm

On the 28 December 2014, a violent and short paroxysmal eruption occurred at the South East Crater (SEC) of Mount Etna that led to the formation of huge niches on the SW and NE flanks of the SEC edifice from which a volume of ~3 × 106 m3 of lava was erupted. Two basaltic lava flows discharged at a rate of ~370 m3/s, reaching a maximum distance of ~5 km. The seismicity during the event was scarce and the eruption was not preceded by any notable ground deformation, which instead was dramatic during and immediately after the event. The SO2 flux associated with the eruption was relatively low and even decreased few days before. Observations suggest that the paroxysm was not related to the ascent of volatile-rich fresh magma from a deep reservoir (dyke intrusion), but instead to a collapse of a portion of SEC, similar to what happens on exogenous andesitic domes. The sudden and fast discharge eventually triggered a depressurization in the shallow volcano plumbing system that drew up fresh magma from depth. Integration of data and observations has allowed to formulate a novel interpretation of mechanism leading volcanic activity at Mt. Etna and on basaltic volcanoes worldwide.

Structural architecture and active deformation pattern in the northern sector of the Aeolian-Tindari-Letojanni fault system (SE Tyrrhenian Sea-NE Sicily) from integrated analysis of field, marine geophysical, seismological and geodetic data

Framed in the current geodynamics of the central Mediterranean, the Aeolian-Tindari-Letojanni fault system is part of a wider NW-SE oriented right-lateral wrench zone which accommodates diverging motion between regional-scale blocks located at the southern edge of the Calabrian Arc. In order to investigate the structural architecture and the active deformation pattern of the northern sector of this tectonic feature, structural observations on-land, high and very-high resolution seismic reflection profiles, swath bathymetry and seismological and geodetic data were merged from the Lipari-Vulcano volcanic complex (central sector of the Aeolian Islands) to the Peloritani Mountains across the Gulf of Patti. Our interpretation shows that the active deformation pattern of the study area is currently expressed by NW-SE trending, right-transtensional en-echelon fault segments whose overlapping gives rise to releasing stepover and pull-apart structures. This structural architecture has favored magma and fluid ascent and the shaping of the Lipari-Vulcano volcanic complex. Similarly, the Gulf of Patti is interpreted as an extensional relay zone between two overlapping, right-lateral NW-SE trending master faults. The structural configuration we reconstruct is also supported by seismological and geodetic data which are consistent with kinematics of the mapped faults. Notably, most of the low-magnitude instrumental seismicity occurs within the relay zones, whilst the largest historical earthquakes (1786, Mw=6.2; 1978, Mw=6.1) are located along the major fault segments.

Inflation Leading to a Slow Slip Event and Volcanic Unrest at Mount Etna in 2016: Insights From CGPS Data

Global Positioning System (CGPS) data from Mt. Etna between May 2015 and September 2016 show intense inflation and a concurrent Slow Slip Event (SSE) from 11 December 2015 to 17 May 2016. In May 2016, an eruptive phase started from the summit craters, temporarily stopping the ongoing inflation. The CGPS data presented here give us the opportunity to determine 1) the source of the inflating body; 2) the strain rate parameters highlighting shear strain rate accumulating along NE Rift and S Rift; 3) the magnitude of the SSE; and 4) possible interaction between modelled sources and other flank structures through stress calculations. By analytical inversion, we find an inflating source 5.5 km under the summit (4.4 km b.s.l) and flank slip in a fragmented shallow structure accommodating displacements equivalent to a magnitude Mw 6.1 earthquake. These large displacements reflect a complex mechanism of rotations indicated by the inversion of CGPS data for strain rate parameters. At the scale of the volcano, these processes can be considered precursors of seismic activity in the eastern flank of the volcano, but concentrated mainly on the northern boundary of the mobile eastern flank along the Pernicana Fault and in the area of the Timpe Fault System.

Antinuclear autoantibodies and pregnancy outcome in women with unexplained recurrent miscarriage

To investigate whether antinuclear autoantibodies (ANA) could be related to the outcome of the successive pregnancy in women with unexplained recurrent miscarriage (uRM).

Ectopic pregnancy in women with recurrent miscarriage

The aim of this study was to investigate the possible association between recurrent miscarriage (RM) and ectopic pregnancy (EP).