Publication Date:
2017-04-04
Description:
In this paper we integrate stratigraphic and sedimentological analyses of the volcaniclastic
deposits, emplaced during initial opening and later widening of the Valle del Bove depression,
with the available stratigraphy of the inner walls, and marine offshore data, structural data, and
magnetic surveys to develop a comprehensive model for the opening of the Valle del Bove
depression. The resulting model adds new insight into the triggering mechanisms of the flank
collapse. Additionally, it suggests a three-stage evolution of the eastern flank of Etna. (1) About
10 Kyr ago, the extinct Ellittico volcano (60 80 (per uniformità anche con Acireale) to 15 Kyr)
collapsed, forming the early Valle del Bove. The collapse produced an avalanche deposit that
spread ESE and formed the base of the Milo Lahar and the Chiancone deposits. (2) The second
stage involved instability-related minor collapses within the valley, causing southward and
westward enlargement of the depression and the emplacement of the debris flow sequence that
comprises the upper part of the Milo Lahar deposit. (3) Available debris that accumulated within
the Valle del Bove from smaller subsequent collapses was deposited at the mouth of the Valle
del Bove in the fluvial sequence that forms most of the exposed part of the Chiancone deposit.
The emplacement of the whole volcaniclastic sequence occurred between 10 and 2 Kyr ago.
Since then, the Valle del Bove has acted as a basin protecting the lower eastern flank of Etna
from lava flows or inundations of volcaniclastic debris.
Description:
Published
Description:
65-75
Description:
3.5. Geologia e storia dei sistemi vulcanici
Description:
open
Keywords:
Etna
;
flank collapse
;
04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
book chapter
