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A hole, usually found in volcanic areas, from which vapors or gases escape.



a small vent or fissure from which hot gases issue. The gases may include H2O, HCl, HF, SO2, CO2, CO, H2S, and H2. If the gases are emitted from magma, the vent is called a primary fumarole; if they are emitted from lava flows or pyroclastics that have not yet solidified, the vent is referred to as a secondary, or rootless, fumarole.

Fumaroles may be located in the crater, on the slopes, or at the foot of a volcano. The gases are emitted under pressure, frequently resulting in a loud hissing or roaring. As the temperature decreases, the water vapor undergoes a transformation to the liquid state. Depending on thermodynamic conditions, certain gases emitted along with the water vapor are dissolved in the liquid water, as are various gases and substances that are produced as a result of reactions with the wall rock and that are encountered on the way to the earth’s surface. In this way, hydrothermal solutions form hot springs in the vicinity of active volcanoes.

The deposition of sublimates of halides, sulfates, native sulfur, and other minerals is associated with fumaroles.


References in periodicals archive ?
It has 67 fumaroles, 29 catch basins and 103 hot springs and the island first used the mineral waters for therapeutic purposes back in the 16th century.
A third serious citation was issued for not having proper warning signs to indicate a potentially hazardous situation at the location of the fumarole.
Most important, the robot will study the vapors rising from volcanic vents called fumaroles.
At the boiling mud pools like Namafjall you smell the fumarole gas and hydrogen sulphide (rotten eggs and all that) before you see them amid the swirling steam.
And throughout the basin, you can hear the roar of the now continuously steaming fumarole at Pork Chop Geyser.
This milky gray lake is actually a flooded fumarole and the second-largest hot spring in the world.
Plumes of smoke, stinking of sulfur, rise out of a nearby fumarole.
NASA's Mars Reconnaissance Orbiter has found that the mounds' composition and their location on the flanks of a volcanic is the best evidence for an intact deposit from a hydrothermal environment-a steam fumarole, or hot spring.
Geysers, Fumaroles and Bubbling Mud: Explore CA's Version of Yellowstone Park
Pupils and staff climbed to the summit of Mount Vesuvius and looked into the steaming crater, as well as exploring the actual crater of the Solfatara volcano with its many fumaroles and mud pools.