Application of differential SAR interferometry for studying eruptive event of 22July 1998 at Mt.Etna

One of the main objectives of the project
“Development and application of remote sensing
methods for the monitoring of active Italian
volcanoes” is directed to an operational use of
differential interferometry as a tool for volcano
monitoring. A first step to achieve this goal is to
test commercial software in order to evaluate
the most suitable for the project purposes. For
testing software, SAR images collected by
ERS2 from May 98 to August 98, before and
after the strong eruptive event occurred on 22
July 98 at Voragine crater of Etna, have been
selected. The explosive event was classified
sub-plinian producing a 12 km high eruptive
column and lapilli fell on land as far as 70 km
south-eastward along the dispersal axis. Pre,
post and across event image pairs have been
processed. In particular the pair 13 May 98-22
July 98, 22 July 98-26 August 98, 13 May 98-26
August 98 are used for testing respectively pre,
post and across event. In first analysis, the
fringes in the differential products show a positive
elevation trend in the summit area of the
volcano. In particular, an increased of about 1,5
fringes in the period pre-event, and a decrement
of 1 fringe in the period post-event is observed.
This result is agreement whit field of deformation
expected in such kind of event, confirming
that the interferometric processing tool used id
suitable for the purpose of the project.

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Tephra fallout from the smaller documented
Subplinian eruption occurred at Mt. Etna on
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