Options
The process of resurgence for Ischia Island (southern Italy) since 55 ka: the laccolith model and implications for eruption forecasting
Language
English
Obiettivo Specifico
2V. Struttura e sistema di alimentazione dei vulcani
Status
Published
JCR Journal
JCR Journal
Peer review journal
Yes
Title of the book
Issue/vol(year)
5/74 (2012)
Pages (printed)
947–961
Issued date
2012
Subjects
04.08. Volcanology
Keywords
Abstract
This study provides an analysis of the evolution
of resurgence from 55 ka for the active volcanic island of
Ischia, southern Italy, using a laccolith model proposed in
previous studies. This paper explores the uplift phases,
eruptive behavior, and associated seismic activity of Ischia
Island, which are important issues as the island has a high
volcanic risk. Through an analysis of stress and strain over
time for laccolith pressurization, it is shown that during
resurgence, Ischia Island has undergone flexural uplift and
progressive fracturing and faulting of the shallow crust
(2 km thick), with an increase in the laccolith’s volume of
at least 80 km3 and an average magma influx of
0.015 m3 s−1. Different elastic and viscoelastic mechanisms
are used to evaluate the modes of stress relaxation due to
this laccolith pressurization phase. Stress relaxation can
occur through uplift and seismicity, without eruption, or
with eruption. It is also shown that large eruptions should
be expected only for long-term uplift of the central part of
Ischia Island (the Mount Epomeo block). In contrast, the
occurrence of small effusive and explosive eruptions should
involve the peripheral areas of the resurgent block, and these
are more likely to occur in the near future than are large
events.
of resurgence from 55 ka for the active volcanic island of
Ischia, southern Italy, using a laccolith model proposed in
previous studies. This paper explores the uplift phases,
eruptive behavior, and associated seismic activity of Ischia
Island, which are important issues as the island has a high
volcanic risk. Through an analysis of stress and strain over
time for laccolith pressurization, it is shown that during
resurgence, Ischia Island has undergone flexural uplift and
progressive fracturing and faulting of the shallow crust
(2 km thick), with an increase in the laccolith’s volume of
at least 80 km3 and an average magma influx of
0.015 m3 s−1. Different elastic and viscoelastic mechanisms
are used to evaluate the modes of stress relaxation due to
this laccolith pressurization phase. Stress relaxation can
occur through uplift and seismicity, without eruption, or
with eruption. It is also shown that large eruptions should
be expected only for long-term uplift of the central part of
Ischia Island (the Mount Epomeo block). In contrast, the
occurrence of small effusive and explosive eruptions should
involve the peripheral areas of the resurgent block, and these
are more likely to occur in the near future than are large
events.
Type
article
File(s)
No Thumbnail Available
Name
Carlino_2012.pdf
Size
781.78 KB
Format
Adobe PDF
Checksum (MD5)
9f48e197d332d43f75e342927c17025b