Cold Water Geysers are normally man-made, where a hole is
drilled through a confining layer into a CO2-laden aquifer. The
borehole provides a path for the pressurized water and CO2 to reach
the surface. Only in a handful of places, such as at faults,
joints, or drilled wells, can the water and CO2 readily escape the
underlying aquifer. Aquifer and plumbing attributes, including
plumbing depth, CO2 concentrations, aquifer yield, and so on,
combine to provide the differing scales and frequencies of
eruptions.
In the same way that steam bubbles expand to displace water in a
hot water geyser, the column of water in a cold water geyser is
pushed up by the expanding of CO2. This "boiling" deep in the
system is comparable to water flashing to steam in a hot water
geyser. As the CO2 out-gasses, it displaces water and starts the
eruption.
At Crystal Geyser, in southeast Utah, after a geyser eruption,
the geyser vent is calm and the water level is below the surface;
like many cold water geysers, Crystal Geyser is a drilled well and
was unintentionally created in the 1930s while drilling for oil. As
time passes, water begins to fill the well column. The well itself
penetrates a confined aquifer with a hydraulic head above the level
of the ground surface, thus the well, if not for the geyser-like
behavior, the well would be expected to possess artesian discharge.
When CO2 and water make it to the surface, CO2 degassing manifests
as increasingly agitated boiling at the vent. Each of these
agitations causes a pressure release for the CO2 below in the
plumbing. Eventually, one of the agitated boils is large enough to
create a chain reaction of CO2 degassing and expansion down the
well: an eruption.
In summary, CO2 and water are competing to get out of the ground
and the effect with limited, small openings, is occasional
eruptions. Aquifer and plumbing attributes (like plumbing depth,
CO2 concentrations, depth to confined aquifer, aquifer yield, etc.)
combine to provide the differing scales and frequencies of
eruptions.
To log this cache you must visit this site and answer the
questions by sending me an email (please do not post answers, they
will be deleted) and post a photo of the
geyser.
1. What is the texture of the ground covered by the geyser
water?
2. What is the temperature of the water?
If you witnessed an eruption, describe what you saw.
While posting a photo of the geyser, include whether the geyser
erupted while you were there, and if so, what time of day was
it?
- Crystal Geyser is the largest cold geyser in the world.
- The geyser erupts sometimes to a height of 40 meters or more.
During 2005, a study of the timing of the eruptions found them to
be bimodal with about 66% of the eruptions about 8 hours after the
previous eruption, and the rest about 22 hours after.
- The current form of the geyser was created by an exploration
well drilled circa 1930 in attempt to locate oil. A large diameter
pipe was installed in the 1990s to prevent people from falling into
the well after the well known story of Jessica McClure.
- The first written record of Crystal Geyser comes from the
report of the John Wesley Powell river expedition, July 13,
1869:
- For more information about Cold Water Geysers, see: Glennon,
J.A. and Pfaff. R.M. (2005) The operation and geography of
carbon-dioxide-driven, cold-water geysers. GOSA Transactions, vol.
9, pp. 184-192.
http://www.uweb.ucsb.edu/~glennon/crystalgeyser/index.htm