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In the framework of VIGOR Project, a national project coordinated by the Institute of Geosciences and Earth Resources (CNR-IGG) and sponsored by the Ministry of Economic Development (MiSE), dedicated to the evaluation of geothermal potential in the regions of the Convergence Objective in Italy (Puglia, Calabria, Campania and Sicily), is expected to evaluate the ability of the territory to heat exchange with the ground for air conditioning of buildings. To identify the conditions for the development of low enthalpy geothermal systems collected and organized on a regional scale geological and stratigraphic data useful for the preparation of a specific thematic mapping, able to represent in a synergistic and simplified way the physical parameters (geological, lithostratigraphic, hydrogeological, thermodynamic) that most influence the subsoil behavior for thermal exchange. The litho-stratigraphic and hydrogeological database created for every region led to the production of different cartographic thematic maps, such as the thermal conductivity (lithological and stratigraphical), the surface geothermal flux, the average annual temperature of air, the climate zoning, the areas of hydrogeological restrictions. To obtain a single representation of the geo-exchange potential of the region, the different thematic maps described must be combined together by means of an algorithm, defined on the basis of the SINTACS methodology. The purpose is to weigh the contributions of the involved parameters and to produce a preliminary synthesis map able to identify the territorial use of geothermal heat pump systems, based on the geological characteristics and in agreement with the existing regulatory constraints.

This paper deals with thermo-mineral groundwater of the Mondragone plain (Campania, southern Italy) and the possibility of exploitation of this low enthalpy geothermal resource. In the NW sector of this plain, at the bottom of Mt. Pizzuto, near the sea, there are thermo-mineral waters of sodium-chloride type, sulfureous and rich in CO2 whose recharge is from the Mt. Pizzuto groundwater body which somehow floating on seawater. In the SE sector of the plain, close to the calcareous Mt. Petrino, a 80 m deep well has intercepted, in the carbonate basement of the plain, thermo-mineral groundwater, sulfureous and rich in CO2, as in the NW sector, but displaying a calcium-bicarbonate composition. The chemical and the isotopic analyses allowed to verify that these types of groundwater are due both to meteoric waters infiltration and to enrichment of endogenous CO2 and H2S, at fairly high temperature. In the case of Mt. Pizzuto, the upwelling gas intercepts evaporitic formation and, probably, causes saltwater intrusion, with a peak from June to September. In the case of the Petrinum well, the gases involve "saline formation groundwater", affecting upwards the groundwater body of Mt. Petrino. Moreover, the rising of the gases increases the dissolution of the carbonate aquifer, determining very high values of HCO3 ions in the thermo-mineral groundwater. The upwelling of the gases occurs along the major fault that crosses NE-SW the plain of Mondragone at the southern edge of the Mt. Petrino. Finally, the understanding of the mineralization patterns allowed to identify in the plain the best location for a geothermal exploration well.

Several "target areas" (each one of 20 km2 ) were selected in Southern Italy for geothermal exploration in the frame of Ministry of Economic Development (MISE) and National Research Council (CNR) joint project: Evaluation of Geothermal Potential in Convergence Regions, (VIGOR) founded by POI Programme 2007-2013. In Campania region a selected area is located between the Mondragone town and the southwestern side of Mt Massico, an horst structure constituted by carbonate and terrigenous sediments. In the selected area there are two thermal springs Sinuessae (SN) known since roman time and "S. Maria dell' Incaldana" (SMI). The characteristic of the two springs are for the first one a discharge of 1-2 L/sec and a T of ~ 54°C and for the second one a low discharge increased by wells until 10 L/s, and T of ~ 33 °C The hydrogeochemical analysis of SN and SMI springs show differences in salt concentration, gas and isotope content, which allows to hypothesize different marine influence and hydrographic system. The origin of these two thermal springs is probably related to faults as a preferential pathway for fluid and gas, like in other geothermal areas of southern Italy. The VIGOR geothermal exploration includes detailed geological and geophysical surveys, hydrogeological investigations and explorative wells. Peculiarly, deep hydrogeological investigations (hydrochemical and isotopic characteristics of groundwater plain and its piezometric pattern, permeability features of the springs area and quantification of groundwater resources) have been developed in order to find the most suitable area to drill a geothermal well.

Together, piston cores C1067, C1201 and C1202 from the continental shelf and slope in the Salerno Gulf and Cilento offshore in the Eastern Tyrrhenian Sea record long-term change (Paleomagnetic Secular Variation - PSV) of Earth's magnetic field during the last approximately 115,000 years. Each core contains the last 24,000 years except for the interval from about 20,000 to 11, 000 years that is absent in C1067 and C1202 because of erosion on the continental slope. The PSV for the Eastern Tyrrhenian Sea is correlated to curves of global relative paleomagnetic field intensity in other marine cores (Stoner et al., 2002) and dated lacustrine records of PSV for western Europe (Thouveny et al., 1990) and Great Britain (Turner and Thompson, 1981). Tephrochronology and radiometric dates (C14 and Ar/Ar) also are used for assigning an age to the record. Along with an improved record of PSV for the Mediterranean region, the PSV in the Salerno Gulf and Cilento offshore piston cores has application for placing time constraints on the marine geology and stratigraphy on the continental shelf and slope. The result is that catastrophic events such as large-scale submarine slumps, volcanic eruptions, turbidite deposition, and abrupt changes in sedimentation rate are dated. The changes in sedimentation rate seem to be linked to global rapid sea level pulses and climate events that induced concurrent reduction and/or abundance in the sediment supply from the adjacent coastal margin.

Studio di fattibilità a Guardia Lombardi: questo studio descrive la valutazione geotermica effettuata nel sito di Guardia Lombardi e la proposta tecnico-economica per lo sviluppo di un progetto impiantistico relativo a risorse geotermiche a media entalpia per la produzione di energia elettrica nel comune di Guardia Lombardi. L'area in esame era già nota da un punto di vista geotermico, poiché mostra un alto flusso di calore individuato dai pozzi per idrocarburi presenti nella regione. La verifica della possibilità di utilizzo della risorsa per la realizzazione dell'impianto e la valutazione della sua realizzabilità, è avvenuta mediante indagini geologiche, idrogeologiche, geochimiche, geofisiche e la realizzazione di una specifica simulazione numerica dinamica dei parametri fisico-chimici del serbatoio, utilizzando i dati forniti dai pozzi per idrocarburi. Questa analisi ha portato alla definizione di una zona potenzialmente utile alla produzione di energia, ubicata in corrispondenza della culminazione strutturale perforata da un pozzo profondo Bonito 1 Dir. sulle quale si è innestato il lavoro di analisi termodinamica, tecnologica ed economica atto a definire la realizzabilità di un sistema di produzione di energia termica, meccanica e quindi elettrica. La simulazione numerica del comportamento del serbatoio geotermico nel settore del pozzo Bonito 1 Dir ha messo in evidenza un potenziale massimo di estrazione sostenibile per almeno 20 anni di 13.5 kg/s, nel caso di pozzo singolo, e di un intervallo di portate comprese tra 10 e 60 kg/s, sostenibili per 25 anni, nel caso di estrazione con reiniezione. Conseguentemente alla scelta del sito di estrazione è stata analizzata la tecnologia più appropriata alla valorizzazione della risorsa geotermica, prendendo in considerazione diverse tecnologie selezionate mediante un'attenta ricerca bibliografica, poste a confronto. Sulla base di considerazioni tecniche, economiche ed ambientali, la scenario preso a riferimento prevede la realizzazione di un doppietto geotermico ovvero di due pozzi profondi per estrazione e reiniezione di fluidi idrotermali.