Long-term variations of fumarole temperatures on Vulcano Island (Italy)

Fumarole temperatures are the ultimate results of many processes that
are encountered by deep fluids during their passage to the surface. Here,
the time variations of high-temperature fumaroles acquired by
continuous monitoring are presented, to show the effects of the forces that
act on the system. Data acquired by continuous monitoring of fumaroles
and the time relationships with the different parameters related to the
activity of the volcanic system are discussed. From 1998 to 2010, the
temperature and compositional changes of fumarolic gases were
monitored at the same time as variations in the number of volcanoseismic
events, which indicate frequent variations of energy release (heat
and mass flow, and seismic strain release). Geochemical modeling applied
to the volcanic system of Vulcano Island suggests that the overall
expansion of magmatic gas through the fractured system is an almost
iso-enthalpic process at depth, which shifts to an adiabatic process at
shallow depth, where the rock permeability increases. Thus, the time
variations of the fumarole temperatures reflect various physical
variations of the system that can either occur at depth or close to the
surface. The temperature monitoring performed in the fumarolic area of
La Fossa Cone showed short-term effects related to rain events, and
negligible effects related to other external agents (ambient temperature
and atmospheric pressure variations). At the same time, the long-term
monitoring highlighted some mean-term and long-term variations. These
last are the main characters observed in the time-series, and they both
appear to be related to endogenous forces that perturb the equilibrium of
this complex geochemical system.

Alparone, S., A. Cannata, S. Gambino, S. Gresta, V. Milluzzo
and P. Montalto (2010). Time-space variation of
the volcano-seismic events at La Fossa (Vulcano, Aeolian
Islands, Italy): new insights into seismic sources in
a hydrothermal system, Bull. Volcanol., 72, 803-816.
Aubert, M. and S. Alparone (2000). Hydrothermal convective
flux variation related to a seismo-tectonic crisis in the
Fossa of Vulcano (Italy), C.R. Geoscience, 330, 603-610.
Aubert, M., S. Diliberto, A. Finizola and Y. Chebli (2008).
Double origin of hydrothermal convective flux variations
in the Fossa of Vulcano (Italy), Bull. Volcanol., 70,
743-751.
Badalamenti, B., S. Falsaperla, G. Neri, P.M. Nuccio and M.
Valenza (1986). Confronto preliminare tra dati sismici e
geochimica nell'area di Lipari, Vulcano Bollettino GNV
1986, 37-47.
Barberi, F., G. Neri, M. Valenza and L. Villari (1991). 1987-
1990 unrest at Vulcano, Acta Vulcanol., 1, 95-105.
Bukumirovich, T., F. Italiano and P.M. Nuccio (1997). The
evolution of a dynamic geological system: the support
of a GISfor geochemical measurements at the fumarole
field of Vulcano, Italy, J. Volcanol. Geotherm. Res., 79,
253-263.
Cannata, A., I.S. Diliberto, S. Alparone, S. Gambino, S.
Gresta, M. Liotta, P. Madonia, V. Milluzzo, M. Aliotta
and P. Montalto (2011). Multiparametric approach in investigating
hydrothermal systems: The case of study of
Vulcano (Aeolian Islands, Italy), Pure Appl. Geophys.;
doi: 10.1007/s00024-011-0297-z.
Chiodini, G., R. Cioni, L. Marini and C. Panichi (1995). Origin
of the fumarolic fluids of Vulcano Island, Italy and
implications for volcanic surveillance, Bull. Volcanol.,
57, 99-110.
Connor, C.B., B.M. Clement,X.D. Song, S.B. Laue and J.
West-Thomas (1993). Continuous monitoring of hightemperature
fumaroles on an active lava dome, Volcan
Colima, Mexico: evidence of mass flow variation in response
to atmospheric forcing, J. Geophys. Res., 98,
19713-19722.
Di Liberto, V., P.M. Nuccio A. and Paonita (2002). Genesis
of chlorine and sulphur in fumarolic emissions at Vulcano
Island (Italy): assessment of pH and redox conditions
in the hydrothermal system, J. Volcanol.
Geotherm. Res., 116, 137-150.
Diliberto, I.S., S. Alparone, M. Liotta and P. Madonia
(2007). Relationship between surface temperatures and
seismic activity at Vulcano (Eolian Islands), Geophys.
Res. Abstr., 9, 08553.
Granieri, D., M.L. Carapezza, G. Chiodini, R. Avino, S. Caliro,
M. Ranaldi, T. Ricci and L. Tarchini (2006). Correlated
increase in CO2 fumarolic content and diffuse
emission from La Fossa crater (Vulcano, Italy): Evidence
of volcanic unrest or increasing gas release from
a stationary deep magma body?, Geophys. Res. Lett.,
33, L13316; doi: 10.1029/2006GL026460.
Harris, A.J.L., L. Lodato, J. Dehn and L. Spampinato (2009).
Thermal characterization of the Vulcano fumarole
field, Bull. Volcanol., 71, 441-458.
Mattia, M., M. Palano, V. Bruno, F. Cannavò, A. Bonaccorso
and S. Gresta (2008). Tectonic features of the Lipari-Vulcano
complex (Aeolian archipelago, Italy) from 10 years
(1996-2006) of GPS data, Terra Nova, 20, 370-377.
Montalto, A. (1996). Signs of potential renewal of eruptive
activity at La Fossa (Vulcano, Aeolian Islands), Bull. Volcanol.,
57, 483-492.
Nuccio, P.M., A. Paonita and F. Sortino (1999). Geochemical
mixing between magmatic and hydrothermal gases:
the case of Vulcano Island, Italy, Earth and planetary
Science letters, 167, 321-333.
Nuccio, P.M. and A. Paonita (2001). Magmatic degassing
of multi-component vapors and assessment of magma
depth: application to Vulcano Island (Italy), Earth Planet.
Sci. Lett., 193, 467-481.
Richter, G., J. Wassermann, M. Zimmerb an M. Ohrnbergera
(2004). Correlation of seismic activity and fumarole
temperature at the Mt. Merapi volcano (Indonesia)
in 2000, Journal of Volcanology and Geothermal Rese-
DILIBERTO
184
185
arch, 135, 331-342.
Tedesco, D. (1995). Fluid geochemistry at Vulcano Island:
A change in the volcanic regime or continuous fluctuation
in the mixing of different systems?, J. Geoph. Reas.,
100 (B3), 4157-4167.
Ventura, G., G. Vilardo, G. Milano and N.A. Pino (1999).
Relationships among crustal structure, volcanism and
strike-slip tectonics in the Lipari-Vulcano volcanic complex
(Aeolian Islands, Southern Tyrrhenian Sea, Italy),
Phys. Earth Planet. Inter., 116, 31-52.