Publication Date:
2017-04-04
Description:
Dikes provide crucial information on how magma
propagates within volcanoes. Somma-Vesuvio (Italy)
consists of the active Vesuvio cone, partly bordered by the
older Mt. Somma edifice. Historical chronicles on the
fissure eruptions in 1694–1944 are matched with an
analytical solution to define the propagation path of the
related dikes and to study any control of the Mt. Somma
relief. The fissures always consisted of the downslope
migration of vents from an open summit conduit, indicating
lateral propagation as the predominant mechanism for
shallow dike emplacement. No fissure emplaced beyond
Mt. Somma, suggesting that its buttressing hinders the
propagation of the radial dikes. An analytical solution is
defined to describe the mechanism of formation of the
laterally propagating dikes and to evaluate the effect of
topography. The application to Somma-Vesuvio suggests
that, under ordinary excess magmatic pressures, the dikes
should not propagate laterally at depths 〉240–480 m below
the surface, as the increased lithostatic pressure requires
magmatic pressures higher than average. This implies that,
when the conduit is open, the lateral emplacement of dikes
is expectable on the S, Wand E slopes. The lack of fissures
N of Mt. Somma is explained by its buttressing, which
hinders dike propagation. Citation: Acocella, V., M. Porreca,
M. Neri, E. Massimi, and M. Mattei (2006), Propagation of dikes
at Vesuvio (Italy) and the effect of Mt. Somma, Geophys. Res.
Lett., 33, L08301, doi:10.1029/2005GL025590.
Description:
Published
Description:
L08301
Description:
reserved
Keywords:
NONE
;
01. Atmosphere::01.01. Atmosphere::01.01.03. Pollution
;
04. Solid Earth::04.04. Geology::04.04.09. Structural geology
;
04. Solid Earth::04.07. Tectonophysics::04.07.07. Tectonics
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
Format:
5097648 bytes
Format:
application/pdf
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