Crustal Deformations Detected by Geodetic Control Network in the Travale Geothermal Area - Tuscany - Italy
|Alberto Beinat, Alessandro Capra, Ivano Dini, Alberto Gubellini, Claudio Marchesini, Aristide Rossi and Luca Vittuari
|geodetic monitoring, subsidence, geothermal deformations
|World Geothermal Congress
|SECTION 7 - Field Management and Monitoring
|A geodetic network, installed in 1988 to integrate an existing precise leveling control network in the Radicondloi-Travale geothermal area (Tuscany, Italy), has also monitored horizontal ground displacements, as part of a study of the geodynamic effects of natural neo-tectonic activity and of the intensive industrial exploitation of the Travale geothermal field.
The network consists of 7 benchmarks distributed along the main distensive fault system on the SW margin of a regional graben-shaped tectonic feature that trends in an Apenninic direction. Measurements on the network were conducted both by conventional geodetic instrumentation (EDMs, thedolites and levels) and by GPS satellite techniques.
Both the expected and observed ground displacements have been very small so far, so that very precise techniques are required to achieve the highest possible accuracy. Various measurement techniques and procedures have been tested, in order to compare the experimental results. The difference between the values measured permits us to evaluate the deformation field. Horizontal ground displacements of about 1 cm per year have been detected.
The analysis and the comparison between methodologies and results are the aims of this paper.