In Laufental the interaction of the four factors
are evident:

After the formation of the Jura through geological folding 10 to 3 million years ago, the Laufental we see today was a wide valley in which the Birs flowed towards the Rhine. The river began to eat into the valley floor and thus initiated the creation of the caves.

 

 

Korrosion

Corrosion

During the first stages of the formation of a cave, water containing carbon dioxide enters through minute cracks and layer interfaces into the rock.
It dissolves the surrounding rock through corrosion
(chemical dissolution). After a sufficiently long time a large passage is created. During this part of their formation, caves are usually entirely filled with water.

Erosion

Erosion

The larger the passages, the more water is able to flow though them. When this carries clay, sand and boulders with it, they grind the rock walls – the rock is eroded. It does not matter if the cave is full of water or has just a stream flowing through it.

Inkasion

Breakdown

When a passage has reached a certain size, roofs and walls may begin to collapse, depending on the stability of the rock. The passage changes its character. If a stream flows through it, the fallen boulders are dissolved by corrosion and carried away by the water. The passage increases in height and can, in extreme cases, break through the ground above
(see Panel 8 Dolines)

Genesis of karst caves

Karst is a generic term for all limestone landscapes with underground drainage. The karst caves in our area can be found mainly on almost horizontal joints or along crevasses. The cave formation is based on penetrating carbonated water, formed from the CO2 of the soil air, which converts the hardly soluble calcium carbonate (15 mg/L) of the limestone into easily soluble calcium bicarbonate (1.5 g/l) and thus chemically dissolves it.

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