Soil diffuse degassing and thermal energy fluxes from the southern Lakki plain, Nisyros (Greece)

Two diffuse soil CO2 flux surveys from the southern Lakki plain show that C O2 is mainly released from the hydrothermal explosion craters. The correspo ndence between high CO2 fluxes and elevated soil temperatures suggests that a flux of hot hydrothermal fluids ascends towards the surface. Steam mostl y condenses near the surface and the heat given off is conductively transfe rred to the atmosphere through the soil, accompanied by a large CO2 flux. T t was calculated, that 68 t d(-1) of hydrothermal CO2 are released through the total surveyed area of similar to1.3 km(2) Admitting that a steam flux of 2200 t d(-1) accompanies this CO2 flux, the thermal energy released thro ugh steam condensation amounts to 58 MW.