Geyser - Misnamed Geysers

Misnamed Geysers

There are various other types of geysers which are different in nature compared to the normal steam-driven geysers. These geysers differ not only in their style of eruption but also in the cause that makes them erupt. Such geysers are not true geysers but are yet referred as such as they all emit water under pressure.

Artificial geysers

In a number of places where there is geothermal activity, wells have been drilled and fitted with impermeable casements that allow them to erupt like geysers. The vents of such geysers are artificial, but are tapped into natural hydrothermal systems. These so-called artificial geysers, technically known as erupting geothermal wells, are not true geysers. Little Old Faithful Geyser, in Calistoga, California, is an example. The geyser erupts from the casing of a well drilled in the late 19th century. According to Dr. John Rinehart in his book A Guide to Geyser Gazing (1976 p. 49), a man had drilled into the geyser in search for water. He had actually "simply opened up a dead geyser".

Cold-water geysers

Cold-water geysers' eruption is similar to that of their hot-water counterparts, except that CO₂ bubbles drive the eruption instead of steam. In cold-water geysers, CO₂-laden water lies in a confined aquifer, in which water and CO₂ are trapped by less permeable overlying strata. This water and CO₂ can escape this strata only in weak regions like faults, joints, or drilled wells. A drilled borehole provides an escape for the pressurized water and CO₂ to reach the surface. The magnitude and frequency of such eruptions depend on various factors such as plumbing depth, CO₂ concentrations, aquifer yield etc. The column of water exerts enough pressure on the gaseous CO₂ so that it remains in the water in small bubbles. When the pressure decreases due to formation of a fissure, the CO₂ bubbles expand. This expansion displaces the water and causes the eruption. Cold-water geysers may look quite similar to their steam-driven counterparts; however, often CO₂-laden water is more white and frothy. The best known of these is probably Crystal Geyser, near Green River, Utah. There are also two cold-water geysers in Germany, Brubbel and Geysir Andernach, and one in Slovakia, Herľany.

Perpetual spouter

This is a natural hot spring that spouts water constantly without stopping for recharge. Some of these are incorrectly called geysers, but because they are not periodic in nature they are not considered true geysers.