How does an eruption of the Geysir Andernach work?
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With an eruption height of up to 60 m, the Geysir Andernach is the highest cold-water geyser in the world. It is located directly on the Rhine about 2 km downstream from the town of Andernach on the Namedyer Werth peninsula. Only here are the geological conditions necessary for the Andernach geyser.
In the course of the last 300 to 400 million years, large geological faults formed as a result of mountain-building processes, which intersect under the Namedyer Werth. Areas where rock packages several thousand metres thick have shifted against each other. This resulted in cracks, crevices, fissures that reach deep into the earth's interior.
Carbon dioxide (CO2) rises through these so-called pathways. TheCO2 comes from the magma deep beneath the Eifel, Germany's youngest volcanic area.
On its way towards the earth's surface, theCO2 encounters groundwater and dissolves in it. The resulting gas-water mixture flows to the geyser well at several depths.
Unlike hot-water geysers, all cold-water geysers require an artificial connection from the earth's surface to the depths, i.e. a borehole or well. The well of the Andernach geyser is a good 350 m deep.
Phase 1 to 4
Das mit CO2 gesättigte Grundwasser fließt durch die Quarzadern in den leeren Brunnen. Dort ist der (Wasser)Druck gering. Dadurch kann/muss sich das Gas aus dem Wasser lösen. Es tritt aus dem Brunnen aus, was man anhand einer kleinen CO2-Wolke über der Brunnenöffnung wahrnehmen kann. Die Luft flimmert.
Wenn die Wassersäule im Brunnen immer höher aufsteigt, nimmt der Wasserdruck zu. Bei vollständig gefülltem Brunnen beträgt er in 350 m Tiefe 35 bar. Dadurch ist eine große Menge CO2 in dem 20 bis 25° Celsius kalten Wasser gelöst, das Gas ist im Wasser quasi unsichtbar. Das Gaswölkchen über der Brunnenöffnung ist verschwunden.
Phase 5 to 8
A short time after the well is full, the geyser eruption phase begins: theCO2 can no longer dissolve in the water, saturation has been reached. Gas bubbles form and rise in the well. The speed and volume of the bubbles increase as they rise. TheCO2 bubbles need space and displace water to the surface. The well overflows. As a result, the pressure of the water or gas-water column in the well decreases. Gas that was previously dissolved in the water is released and displaces more water to the earth's surface. A domino effect sets in.
Phase 9
The main phase of the geyser eruption is reached when more and more gas is released from the water and the gas bubbles coalesce into ever larger bubbles on their way upwards. The small diameter of the well pipe of only 15 cm causes the bubbles to expand primarily vertically. This results in 10 to 15 m long so-called piston bubbles. These tear and pull a total of approx. 8,000 liters of water upwards and hurl it out of the geyser fountain in a pulsating manner. The geyser fountain gets higher and higher, up to a height of 60 meters. Gradually the fountain empties, the fountain becomes smaller and smaller and finally disappears completely. The entire geyser eruption lasts about 15 minutes.
Phase 10
Once again, theCO2-saturated groundwater flows into the now empty well. The gas dissolves out of the water, the flickering above the well opening can be seen again. 110 to 120 minutes later, the time has come: the well is full and the next geyser eruption begins...
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Nice excursion with a nice explanation. We had a very nice trip to the geyser. The geyser was very impressive to see. Special thanks to the staff, who were very friendly and helpful and made the trip possible for us (assistance due to walking difficulties).
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Highly recommended! An interactive tour explains the formation of a geyser in a fun way. The absolute highlight is the boat trip to the geyser, where you can see the natural spectacle live.
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We were there with the whole family, grandparents, parents and children! There was something for everyone and it was very interesting! Simply a super great day spent with the whole family!
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It is a wonderful hands-on museum. Even small children can try out and explore here. Older children and adults can learn lots of new things. The accompanying boat trip is a highlight. The geyser experience at the end is just great. The staff are polite and friendly. Very helpful. The museum is also suitable for baby carriages. The parking spaces are scarce, but with a bit of luck you ...
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The boat trip to the geyser was informative and we were told about the formation of the geyser. There was a lot of staff on site who were keen to pass on their knowledge. A conversation with the staff was very helpful and informative.
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