Inside Mt. Vesuvius: a new method to look at the seismic (velocity and attenuation) tomographic imaging

Mt. Vesuvius have been obtained using the programming facilities as
well as the enhanced graphical power of Mathematica8TM. The velocity
and attenuation space distributions, already calculated inverting respectively
P-wave travel times and amplitude spectra of local VT quakes,
are first optimally interpolated and then graphically represented in a new
Mathematica8TM code notebook (a powerful computational document
with more facilities than a simple code) developed by the present authors.
The notebook aims at interactively and friendly representing 3D volume
distributions of velocity and attenuation parameters. The user can easily
obtain vertical sections (N-S, E-W, NE-SW and NW-SE oriented) and define
color scales to represent velocity or attenuation variations or prefer
iso-surface plots to represent the pattern of peculiar geological structures.
The use of dynamic graphical representation, allowing the sliding of any
(horizontal and/or vertical) slice through the volume under study, gives
an unusual and powerful vision of any small velocity or attenuation
anomaly. The (open source) code, coupled with the friendly use of internal
routines of Mathematica, allows to adapt the graphical representation
to any user necessity. The method appears to be particularly adapt to
represent attenuation images, where the space variations of the parameters
are strong with respect to their average. The 3-D plots of the interpolated
velocity and attenuation fields enhance the image of Mt. Vesuvius
structure, evidencing low-velocity associated with high attenuation
anomalies which appeared unfocused in the plots reported by Scarpa et al.
[2002] and De Siena et al. [2009].

Hypocentral locations are taken from
GEOVES DataBase (Istituto Nazionale di Geofisica e Vulcanologia -
INGV, Osservatorio Vesuviano). Raw data from tomography studies
were released by their authors. The software described in this
paper has been prepared in the framework of the projects: V2-“Precursori
di Eruzioni in Vulcani Quiescenti: Campi Flegrei e Vulcano”.
Convenzione INGV-DPC (2012-2013); EPHESTOS CGL2011-2949-
C02-01 (University of Granada, Instituto Andaluz de Geofísica);
MEDiterranean SUpersite Volcanoes (MED-SUV) FP7 ENV.2012.
6.4-2 Grant agreement no. 308665. (European Community).