The Eastern Carpathians are characterized by intense gas emissions starting from the Neogene to Quaternary volcanic structures and occurring also far away from these, in the Cretaceous flysch units. This is the most intensive degassing area from Romania.
The gas emissions appear in different forms: dry gas, named mofettes and bubbling gas when they are accompanied by groundwater. The major components of these gas emissions are: CO2, CH4, N2 and sometimes H2S. Recent studies reveal a magmatic contribution up to 60% in these emissions. Gases are also present dissolved in groundwater and transported to the surface by CO2-rich springs. Besides these visible emissions, the gases come to the surface as diffuse degassing from the soil.
Consuming raw CO2-rich mineral water, directly from the source, is very popular in the area. It is appreciated that thousands of people from the Eastern Carpathians consume non-bottled mineral water on a daily basis, using local mineral springs and wells as their main source of drinking water, as an alternative to tap water.
The mineral waters are associated with medical/balneological services; spas and medical treatment centres, (e.g., at Borsec, Sângeorz-Băi, Băile Homorod, Băile Harghita,
Băile Tușnad, Covasna) have been developed in the Eastern Carpathians, all of them dependent on the regional water resource and its quality.
The gas emissions also represent an important social-cultural-medical factor of the region, the mofettes are often used traditionally for therapeutic effects.