|Helatoba from hela (tapanuli word), which means is son-in-law.
Helatoba active volcano is a type of Fumarole where there are 43 points that emit hot-water and there are 7 points that remove bursts of sulfur in the path along the 40 km.
geothermal in Sipoholon area consists of hot springs, gas boils and solfatara. Hot water type consists of chloride type, bicarbonate type and sulfate type. The fluid temperature in the reservoir ranges from 142′-230’C with an estimated potential rate of 140 MWe.