| Abstract |
Vapor-dominated geothermal systems have been produced for almost 90 years. But the storage mechanism is still in doubt. The fluid must be stored as a liquid, yet the pressure at reservoir temperature is well into the superheated steam region for flat-surface thermodynamics. One popular mechanism is that the liquid phase is a brine. Another possibility is that the liquid phase is adsorbed. A study of the Big Geysers shallow steam production indicates that adsorption is a reasonable mechanism. |