Hydrogeological insights at Stromboli volcano (Italy) from geoelectrical, temperature and CO2 soil degassing investigations
- Publication date
- Publisher
- Agu
Abstract
Finding the geometry of aquifers in an active volcano is
important for evaluating the hazards associated with phreatomagmatic
phenomena and incidentally to address the
problem of water supply. A combination of electrical
resistivity tomography (ERT), self-potential, CO2, and
temperature measurements provides insights about the
location and pattern of ground water flow at Stromboli
volcano. The measurements were conducted along a NE-SW
profile across the island from Scari to Ginostra, crossing the
summit (Pizzo) area. ERT data (electrode spacing 20 m,
depth of penetration of 200 m) shows the shallow
architecture through the distribution of the resistivities. The
hydrothermal system is characterized by low values of the
resistivity (<50 W m) while the surrounding rocks are
resistive (>2000 W m) except on the North-East flank of
the volcano where a cold aquifer is detected at a depth of
80 m (resistivity in the range 70–300 W m). CO2 and
temperature measurements corroborate the delineation of the
hydrothermal body in the summit part of the volcano while a
negative self-potential anomaly underlines the position of
the cold aquifer