Exploring for geothermal resources in Greece

In Greece the geothermal areas are located in regions of Quaternary or Miocene volcanism and in continental basins of high heat flow. The existence of high-temperature (>200 °C) resources has been proven by deep drilling on the islands of Milos and Nisyros and inferred on the island of Santorini by its active volcanism. Elsewhere, geological investigations, geochemical analyses of thermal springs and shallow drilling have identified many low-temperature (<100 °C) reservoirs, utilized for spas and greenhouse/soil heating. Ternary K–Na–Mg geothermometer data suggest deep, medium-temperature resources (100–200 °C) in Sousaki, the islands of Samothraki, Chios and Lesvos, in the basins of Nestos River Delta and Alexandroupolis and in the graben of Sperchios River. In the basins of northern Greece these resources are also inferred from deep oil exploration well data.