The Impact of Massive Exploitation in the Surface Manifestations at Ulubelu Geothermal Field, Indonesia
Anjani PUSPADIANTI, Jodhi P. GIRIARSO, MULYANTO, Fernando PASARIBU, Marihot S.P. SILABAN
[PT. Pertamina Geothermal Energy, Indonesia]
Ulubelu Geothermal Field has been operating since 2012 with an installed capacity of for install capacity 110 MW. The baseline geochemistry of surface manifestations determined in 2012. Due to the necessity of electricity in Indonesia, the addition of 2 x 55 MW for Unit 3 and 4 has been commissioning since 2016 and 2017. Monitoring geochemistry of surface manifestation conducted in 2017. The increasing of fumaroles temperature and steam fraction, which postulated as upflow zone, shows that meteoric fluid decreased compared to the contribution of reservoir fluid. The reinjection breakthrough was affected by fumaroles, it remarked by the dropping of NCG and was proved by the geochemical production monitoring as well. Declining temperature and dilution of chloride was occured at neutral chloride hot springs in Way Panas, which postulated as an outflow zone area. It indicates that the reduction of reservoir fluid was occured in the too hot springs due to the massive mass extraction in the upflow zone through the outflow zone.
|        Topic: Geochemistry||Paper Number: 14007|