A "volcanic eruption" in the middle of the forest! Lava has not been spewed out for a long time, but the carbonated water that "bubbles" out of the ground here has a lot to do with volcanoes. Buried a few hundred meters below is a lot of organic material that was deposited here in a sea and then buried by lava and ash from the volcanoes. This organic material is now slowly being converted into peat and coal - and in the process, carbon dioxide is being produced and bubbling out of here!
The formation of the "Brodlsulz"
The Brodelsulz is located at the southeast edge of a volcanic tongue. According to Prof. Artur Winkler Hermaden, precipitation waters penetrate through volcanic fissures several hundred meters deep, where they meet gases that are still warm. At the foot of volcanic plates these springs, enriched with gases and minerals, come to light again. According to recent geological findings, during the Late Tertiary period, when the southeast of Styria was flooded several times (Pannonian sea, Sarmatian brackish water, Tortonian sea), organic materials were deposited. These materials were subsequently covered by mud and lava. They are currently undergoing a peatification/charring process. The resulting carbonic acid rises to the surface through fissures in the earth and emerges with water, as here.