This presentation aims at describing a state of the art of the existing and/or
promising geophysical methods for geothermal exploration and recognition of
geological structures and specific physical properties at depth. It makes a brief
review of the geophysical methods applied in the past 20 years in Europe and, in
particular, to five selected sites in different geological contexts: volcanic
(Hengill, Iceland, and Bouillante, France), metamorphic (Larderello, Italy), deep
sediments (Groß Schönebeck, Germany), plus the European HDR of Soultz-sous-Forêts,
where geophysical methods were focused on recognition of deep fractured reservoirs.
Three aspects are pointed out: efficiency, precision and uncertainty of the results,
and innovation. It is concluded that the methods used up to now, allow building a
preliminary conceptual model of the reservoir in conjunction with exploration wells
data. Nevertheless, the improvement of this conceptual model to decrease the drilling
risk of the exploitation wells needs more integration between different methods,
advanced 3 D modelling coupled with thermo-hydrodynamic modelling and rock physics
measurements. This will be one of the objectives of the I-GET project, funded by the FP6.

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