Carbon Dioxide (CO2) Survey at Makaroyen Village in Kotamobagu Geothermal Field, North Sulawesi, Indonesia

Abstract

Kotamobagu geothermal field is one of the prospects of geothermal development in North Sulawesi, Indonesia. We conducted soil air gas survey in Kotamobagu, mainly within Makaroyen village, on the foot of Ambang Mountain. Concentrations of CO2, were measured for 20 sampling points in the area of 1.0 km EW and 1.0 km NW with elevation around 1000 m above sea level. High concentrations of CO2, 1% to 3.8%, were mainly measured in the centre, northeast and east of the study area whereas lower concentrations to the south and to the west. High concentration of CO2 above 1.0% was detected in the centre, northeast and east of the area Makaroyen village. The presence of flow path of high temperature fluid and heat source is expected below the areas with high concentrations of CO2.