Abstract in atti di convegno, 2023, ENG, 10.5194/egusphere-egu23-16132

Multiscale imaging of low-enthalpy geothermal reservoir of the Phlegraean Fields caldera from gravity and resistivity data

Milano M.; Cavuoto G.; Corniello A.; Di Fiore V.; Fedi M.; Massarotti N.; Pelosi N.; Punzo M.; Tarallo D.; Donnarumma G.P.; Iorio M.

University of Naples Federico II, Earth, Environment and Resources Sciences, Naples, Italy; CNR-ISPC, Napoli, Italy; University of Naples Federico II, Dipartimento di Ingegneria civile, edile e ambientale, Naples, Italy; CNR-ISPC, Napoli, Italy; University of Naples Federico II, Earth, Environment and Resources Sciences, Naples, Italy; Università degli Studi di Napoli Parthenope, Naples, Italy; CNR-ISPC, Napoli, Italy; CNR-ISPC, Napoli, Italy; CNR-ISPC, Napoli, Italy; Graded S.p.A., Naples, Italy; CNR-ISMAR, Napoli, Italy;

The central-eastern sector of the Phlegraean Fields caldera, southern Italy, is one of the most intensely studied and monitored volcanic active area of the word. This area reveals typical characters of a high- enthalpy geothermal systems. However, recently the presence of two different geothermal reservoirs has been outlined: one located in the central sector dominated by highly active vapours generated by episodic arrival of CO2-rich magmatic fluids and the other one located in the eastern sector (Agnano zone) characterized by a shallow (400-500 m b.s.l.) still hot reservoir, heated by the upward circulation of deep no magmatic hot vapor. In this study we present preliminary results deriving from the integration of different geophysical surveys carried out in the Agnano plain area, in the frame of the GEOGRID research project. We acquired high-resolution gravity data along two parallel profiles and we investigated the depth, shape and density contrast of the subsurface structures by the CompactDEXP (CDEXP) method, a multiscale iterative imaging technique based on the DEXP method. The resulting density models, together with DC resistivity and stratigraphic data, outlines the presence of a complex morphology of the Agnano subsoil characterized by a horst-graben structure. The importance of the structural lines identified by geophysical data, is also confirmed by the alignment of correlate outcropping thermal waters.

EGU General Assembly 2023, Vienna, Austria, 24-28/04/2023

Keywords

geophysical surveys, gravity data, resistivity data, Phlegraean Fields caldera

CNR authors

Iorio Marina, Pelosi Nicola, Di Fiore Vincenzo, Cavuoto Giuseppe, Punzo Michele, Tarallo Daniela

CNR institutes

ISMAR – Istituto di scienze marine, ISPC – Istituto di Scienze del Patrimonio Culturale