Publication Date:
2017-04-04
Description:
The Solfatara is one of the major volcanoes of the Phlegrean Fields (Campi Flegrei) volcanic
complex, and it is located in a densely populated area a few kilometres west of the city
of Naples. It is an active resurgent caldera that has been characterized by a rich history of
surface–ground deformation and soil diffuse degassing and fumarolic emissions, which are
indications of the top of a hydrothermal plume. A seismic survey was completed in May 2009
for the characterization of the main subsurface features of the Solfatara. Using the complete
data set, we have carried out surface wave inversion with high spatial resolution. A classical
minimization of a least-squares objective function was first computed to retrieve the dispersion
curves of the surface waves. Then, the fitting procedure between the data and a three-sedimentlayer
forward model was carried out (to a depth of 7 m), using an improved version of the
neighbourhood algorithm. The inversion results indicate a NE-SW fault, which is not visible
at the surface. This was confirmed by a temperature survey conducted in 2010. A passive
seismic experiment localized the ambient noise sources that correlate well with the areas of
high CO2 flux and high soil temperatures. Finally, considering that the intrinsic attenuation is
proportional to the frequency, a centroid analysis provides an overview of the attenuation of
the seismic waves, which is closely linked to the petrophysical properties of the rock. These
different approaches that merge complete active and passive seismic data with soil temperature
and CO2 flux maps confirm the presence of the hydrothermal system plume. Some properties
of the top of the plume are indicated and localized.
Description:
Published
Description:
1725–1733
Description:
1.2. TTC - Sorveglianza geochimica delle aree vulcaniche attive
Description:
2.4. TTC - Laboratori di geochimica dei fluidi
Description:
4.5. Studi sul degassamento naturale e sui gas petroliferi
Description:
JCR Journal
Description:
restricted
Keywords:
Inverse theory
;
Tomography
;
Hydrothermal systems
;
Europe
;
03. Hydrosphere::03.02. Hydrology::03.02.04. Measurements and monitoring
;
03. Hydrosphere::03.04. Chemical and biological::03.04.05. Gases
;
04. Solid Earth::04.04. Geology::04.04.11. Instruments and techniques
;
04. Solid Earth::04.04. Geology::04.04.12. Fluid Geochemistry
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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