High resolution velocity structure beneath Mount Vesuvius from seismic array data

Abstract

[1] A high resolution P-wave image of Mt. Vesuvius edifice has been derived from simultaneous inversion of travel times and hypocentral parameters of local earthquakes, land based shots and small aperture array data. The results give details down to 300-500 m. The relocated local seismicity appears to extend down to 5 km below the central crater, distributed in a major cluster, centered at 3 km below the central crater and in a minor group, with diffuse hypocenters inside the volcanic edifice. The two clusters are separated by an anomalously high Vp region at around 1 km depth. A zone with high Vp/Vs in the upper layers is interpreted as produced by the presence of intense fluid circulation. The highest energy quakes (up to M = 3.6) are located in the deeper cluster, in a high P-wave velocity zone. Our results favor an interpretation in terms of absence of shallow magma reservoirs.

Seismic tomography of Central São Miguel, Azores

“…Taupo volcanic zone [Sherburn et al, 2003] [Nicholson and Simpson, 1985;Bonner et al, 1998;Patané et al, 2002]. In spite of that, in volcanic environments high Vp/Vs values at shallow depths can be generally associated with saturated highly fractured materials (as in Vesuvio [Scarpa et al, 2002] and Kilauea [Hansen et al, 2004]). Deep, high Vp/Vs values are rather related to bodies of partial melt (as in Etna [Patané et al, 2006], Yellowstone [Husen et al, 2004] and Long Valley [Sanders et al, 1995]).…”

“…For these reasons, it has been applied to investigate the interior of several volcanoes such as Redoubt [Benz et al, 1996], Etna [Villaseñor et al, 1998], Kilauea [Dawson et al, 1999] and Vesuvio [Scarpa et al, 2002], and calderas, for example Campi Flegrei [Zollo et al, 2003].…”

A reappraisal of shear wave splitting parameters from Italian active volcanic areas through a semiautomatic algorithm

“…The velocity structure beneath Mt. Vesuvius is well known and has been deduced by seismic tomography at different resolution scales (Auger et al 2001;Scarpa et al 2002). Moreover, the volcano seismicity pattern is described in many papers, from which we synthesize briefly the main features of earthquake spatiotemporal distribution: the seismicity appears to extend down to 5 km below the central crater, with most of the energy clustered in a volume spanning 2 km in depth, positioned at the border between the limestone basement and the volcanic edifice.…”

Motivations for muon radiography of active volcanoes

“…The upper part of the cone was formed during the persistent activity between 1631 and 1944, when Vesuvius was in the open-conduit state. A reconstruction of the morphology of the Vesuvius cone in the period between 1631 and 1944 was generated by Scarpato et al (2005), based on a rich collection of historical pictures of the volcano .…”

“…For this reason, in parallel with the analysis of past eruptions, much effort has been extended in past years in experiments investigating the interior of the volcanoes (e.g. Vesuvius) with different techniques, including deep drilling (Cassano and La Torre, 1987;Principe et al, 1987), passive (Scarpa et al, 2002) and active (Zollo et al, 1996(Zollo et al, , 2002 seismic tomography, geoelectrics and magnetotellurics (Di Maio et al, 1998) and gravimetry (Cella et al, 2007). Each of these methods has its own characteristic advantages and drawbacks, and a complete description of the volcano interior can be achieved only through a synthesis of combined investigations with all the available techniques.…”