Evidence of fractures on seismic data for geothermal exploration

Abstract

The deep geothermal reservoirs in the Larderello- Travale field (southern Tuscany) are found in intensively fractured portions of intrusive/metamorphic rocks. Therefore, the geothermal exploration carried out by Enel Green Power has been in search of possible fracture signatures that could be retrieved from the analysis of geophysical data. In the present work, thanks to the availability of borehole logs and 3D seismic data, we assess the feasibility of finding seismic markers which may pinpoint fractured levels. These seismic markers include either pre-stack and post-stack reflection attributes and they all require tailored seismic processing sequences to correct for amplitude and phase distortions, noise contamination and to preserve azimuthal and offset variations.