Results of Deep Drilling in the Larderello-Travale/Radicondoli Geothermal Area

Abstract

Deep dnlling showed that the Larderello and Travale-Radicondoli geothermal fields, which for many years were regarded as two independent systems, belong to a single geothermal area. At below sea level the 300?C isotherm covers approximately and includes both fields and the area in between. Productive levels have been discovered in the metamorphic basement to a depth of about 4000 m. The success ratio of the deep drilling has been about 60% with flowrates ranging between 8 and (average values per productive well in the areas of Larderello and Travale-Radicondoli). The geothermal system was found to be steam-dominated everywhere. The shallow well drainage has extended to depths of m in the most exploited areas, while in those not affected by drainage the reservoir pressure is still about 7