Tracking magma dynamics by Laser Ablation (LA)-ICPMS trace element analysis of glass in volcanic ash: the 1995 activity of Mt. Etna

Glass fragments in tephra erupted at Mt. Etna from
May to December 1995 have been analyzed by laser ablation
ICPMS. The trace element compositional variability of
ashes deposited during this interval reveals the presence of
discrete magma batches with different crystallization
degrees in the shallow plumbing system. From May to
October a highly crystalline magma is predominant within
the conduit with only minor sporadic input of fresh and more
primitive magma batches. After October new and less
evolved magma batches become more prevalent and become
progressively homogenized within more evolved resident
magma. In December ashes closely match the chemistry of
the volcanics subsequently erupted till February 1996. This
study demonstrates that the trace element characterization of
ashes has important implications for volcanic monitoring
and is a useful tool for the forecasting of paroxysmal events
at Mt. Etna.

Andronico, D., et al. (2005), A multi-disciplinary study of the 2002– 03
Etna eruption: Insights into a complex plumbing system, Bull. Volcanol.,
67, 314–330.
Armienti, P., M. D’Orazio, F. Innocenti, S. Tonarini, and L. Villari (1996),
October 1995 – February 1996 Mt. Etna explosive activity: Trace
element and isotopic constraints on the feeding system, Acta Vulcanol.,
8, 1–6.
Berlo, K., J. Blundy, S. Turner, K. Cashman, C. Hawkesworth, and S. Black
(2004), Geochemical precursors to volcanic activity at Mount St. Helens,
USA, Science, 306, 1167– 1169.
Branca, S., and P. Del Carlo (2005), Types of eruptions of Etna Volcano AD
1670 – 2003: Implications for short-term eruptive behaviour, Bull.
Volcanol., 67, 732–742.
Brenan, J. M., F. J. Ryerson, and H. F. Shaw (1998), The role of aqueous
fluids in the slab-to-mantle transfer of boron, beryllium and lithium during
subduction: Experiments and models, Geochim. Cosmochim. Acta,
62, 3337– 3347.
Cashman, K. V., and R. P. Hoblitt (2004), Magmatic precursors to the 18 May
1980 eruption of Mount St. Helens, USA, Geology, 32, 141– 144.
Coltelli, M., M. Pompilio, P. Del Carlo, S. Calvari, S. Pannucci, and
V. Scribano (1998), Mt. Etna: The eruptive activity, Acta Vulcanol.,
10, 141– 148.
Corsaro, R. A., and M. Pompilio (2004a), Dynamics of magmas at Mount
Etna, in Mt. Etna: Volcano Laboratory, Geophys. Monogr. Ser., vol. 143,
edited by A. Bonaccorso et al., pp. 91–110, AGU, Washington, D. C.
Corsaro, R. A., and M. Pompilio (2004b), Magma dynamics in the shallow
plumbing system of Mt. Etna as recorded by compositional variations in
volcanics of recent summit activity (1995– 1999), J. Volcanol. Geotherm.
Res., 137, 55– 71.
Doglioni, C., F. Innocenti, and G. Mariotti (2001), Why Mt Etna?, Terra
Nova, 13, 25–31.
Kessel, R., M. W. Schmidt, P. Ulmer, and T. Pettke (2005), Trace element
signature of subduction-zone fluids, melts and supercritical liquids at
120– 180 km depth, Nature, 437, 724–727.
La Delfa, S., G. Patane`, R. Clocchiatti, J. L. Joron, and J. C. Tanguy (2001),
Activity of Mount Etna preceding the February 1999 fissure eruption:
Inferred mechanism from seismological and geochemical data, J. Volcanol.
Geotherm. Res., 105, 121– 139.
Morra, V., M. Lustrino, L. Melluso, G. Ricci, R. Vannucci, A. Zanetti, and
F. d’Amelio (2003), Trace element partition coefficients between feldspar,
clinopyroxene, biotite, Ti-magnetite, apatite and felsic potassic glass from
Campi Flegrei (S. Italy), Geophys. Res. Abs., 5, Abstract 05966.
Taddeucci, J., M. Pompilio, and P. Scarlato (2002), Monitoring the
explosive activity of the July– August 2001 eruption of Mt. Etna (Italy)
by ash characterization, Geophys. Res. Lett., 29(8), 1230, doi:10.1029/
2001GL014372.
Taddeucci, J., M. Pompilio, and P. Scarlato (2004a), Conduit processes
during the July –August 2001 explosive activity of Mt. Etna (Italy):
Inferences from glass chemistry and crystal size distribution of ash
particles, J. Volcanol. Geotherm. Res., 137, 33– 54.
Taddeucci, J., O. Spieler, B. Kennedy, M. Pompilio, D. B. Dingwell, and
P. Scarlato (2004b), Experimental and analytical modeling of basaltic
ash explosions at Mount Etna, Italy, 2001, J. Geophys. Res., 109,
B08203, doi:10.1029/2003JB002952.
Tiepolo, M., P. Bottazzi, M. Palenzona, and R. Vannucci (2002), A laser
probe coupled with ICP-double-focusing sector-field mass spectrometer
for in situ analysis of geological samples and U-Pb dating of zircon, Can.
Mineral., 41, 259–272.
Tonarini, S., P. Armienti, M. D’Orazio, F. Innocenti, M. Pompilio, and
R. Petrini (1995), Geochemical and isotopic monitoring of Mt. Etna
1989– 1993 eruptive activity: Bearing on the shallow feeding system,
J. Volcanol. Geotherm. Res., 64, 95– 115.
Vaggelli, G., F. Olmi, and S. Conticelli (1999), Evaluation of analytical
errors during microprobe analyses of silicate minerals international
reference samples, Acta Volcanol., 11, 297–303.
Vannucci, R., P. Bottazzi, E. Wulff-Pedersen, and E. R. Neumann (1998),
Partitioning of REE, Y, Sr, Zr and Ti between clinopyroxene and silicate
melts in the mantle under La Palma (Canary Islands): Implications for the
nature of the metasomatic agents, Earth Planet. Sci. Lett., 158, 39– 51.
Watanabe, K., T. Danhara, K. Terai, and T. Yamashita (1999), Juvenile volcanic
glass erupted before the appearance of the 1991 lava dome, Unzen
volcano, Kyushu, Japan, J. Volcanol. Geotherm. Res., 89, 113– 121