Thermal and geochemical constraint on the deep magmatic structure
of Mt. Vesuvius
Journal of Volcanology and Geothermal Research, 133 (1-4):
1--12 (May 30, 2004)DOI: 10.1016/S0377-0273(03)00387-1
Abstract
A review of available and new isotopic data on rocks from Mt. Vesuvius
together with geophysical and mineralogical data allow us to define
a deep complex magmatic reservoir where mantle-derived magmas arrive,
stagnate and differentiate, and to constrain a thermal model, which
describes the history and present state of the reservoir and its
surrounding rocks. The top of the reservoir is located at about 8
km depth, and it extends discontinuously down to 20 km depth. The
reservoir is hosted in densely fractured continental crustal rocks,
where magmas and crust can interact, and, according to thermal modeling
results, has been fed more than once in the last 400 ka. The hypothesis
of crustal contamination is favored by the high temperatures reached
by crustal rocks as a consequence of repetitive intrusions of magma.
From the deep reservoir magmas rise to form shallow magma chambers
at different depths, as already known in the literature, where they
can undergo low-pressure differentiation and mixing and feed the
volcanic activity.