Creux-Genat
| Creux-Genat | ||||
|---|---|---|---|---|
 The water-filled spring funnel, shortly after a pouring period in May 2013 |
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| location | ||||
| Country or region | Porrentruy District , Canton Jura , ( Switzerland ) | |||
| Coordinates | 47 ° 23 '47 " N , 7 ° 1' 38" E | |||
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| geology | ||||
| Mountains | law | |||
| Source type | Karst spring | |||
| Exit type | Source pot | |||
| rock | limestone | |||
| Hydrology | ||||
| River system | Rhone | |||
| Receiving waters | Ajoulote → Allaine → Doubs → Saône → Rhone → Mediterranean | |||
| depth | 15 m | |||
The temporary karst spring Creux-Genat (also called Creugenat ) is located on the municipality of Haute-Ajoie in the canton of Jura in Switzerland .
The entrance to the cave is in a dry valley in the Chevenez area , which is drained by the subterranean Ajoulote stream. The Ajoulote comes to light in the middle of Pruntrut in the Beuchire spring and flows into the Allaine . The entrance to the cave is at the foot of a 15 m deep sinkhole .
The karst spring pours water on average about four to five times a year, mostly after prolonged rainfall or during periods of intense snowmelt . In extreme floods, a water volume of up to 20 m³ / second flows out of the sinkhole and floods the valley.
expansion
The cave system has a measured length of 2125 m and a vertical extension of 20 m. Longer stretches of the cave are under water.
history
The first scientific investigations into the phenomenon of water eruptions from the Creux-Genat took place at the end of the 18th century. The first speleological research was carried out in 1933. The first dive in the source siphon took place in the winter of 1934 . After several diving advances using a helmet diving device and an air hose, a surface was found 125 m away from the entrance.
The second research period began in 1973. The research was advanced by means of modern equipment. In the following ten years, the corridor system could be explored based on today's level of knowledge. Another advance was made in the summer of 2000. During this advance the source siphon was pumped out and the corridor system was driven over a long distance.
The duct systems of the Creux-Genat have not yet been conclusively researched. Further research is reserved for cave divers .
geology
The cave passages follow the crevices and layer joints in the limestone of the Kimmeridgien and Séquanien.
etymology
The name Creux-Genat (also called Creugenat) means something like Hexenloch in the Jurassic dialect.
See also
Web links
- Archive page Estavelle du Creugenat, Jura (from the magazine Stalactite No. 2002, pages 41–50) ( Memento from April 24, 2008 in the Internet Archive )
- Archive page topographic plans of the entrance area ( Memento from April 21, 2008 in the Internet Archive )