In these times of growing need for new energy sources, geothermal has shown great promise. High temperature geothermal resources occur in areas of natural volcanic activity where the earth's magma is close enough to the surface to encounter ground water. These areas are scattered around the world in such places as Hawaii, Iceland, Italy, New Zealand, and the Geysers area of Sonoma County, California. They are often found near cracks in the Earth's crust where tectonic plates are pulling apart.
Geothermal steam is a green, relatively nonpolluting energy source that can provide power on a scale large enough to make a significant contribution to our needs. One of the challenges of geothermal development is noise emission. This occurs during the drilling process, primarily after a well encounters steam. Drilling must continue until there is sufficient steam volume and pressure to support a power plant.