Theis contributed to a study about thermal springs in the Alps.
In this paper the authors used a newly created database with information about temperature, discharge, hydrochemistry and stable water isotopes composition of groundwater from hot springs in the Alps to study deep groundwater flow in mountain belts and its contribution to the groundwater and heat budget.
The amount of groundwater that circulate to deeper depths and its influence on subsurface temperatures is largely unknown. In this paper the authors found out that all studied springs with isotopic data in the Alps are fed exclusively by meteoric water. On average the circulation depth of spring water is around 2,300 m but can reach up to 4,700 m depth. Around 0,1 % of the overall groundwater in the Alps is groundwater from hot springs. The hot groundwater in springs result in a thermal footprint of 7 km2 around the spring location.
Read more at: https://doi.org/10.1029/2020GL090134