Gundih CCS pilot project is located within the Gundih gas field operated by PERTAMINA at Central Java, Indonesia. Geologically, this field is part of East Java Basin, which is well known as prolific hydrocarbon basin in South East Asia region. Gundih field and surrounding area is a gas field, which has been in production since the end of 2013. CO2 content, which is generated directly from this field, is 21% of the produced gas. Government of Indonesia is highly committed in reducing CO2 emissions. Therefore, flaring CO2 to the atmosphere is not an option anymore. CCS by injection to depleted oil and gas reservoir known as geological storage will be the best choice. The main objectives of CCS pilot study is to understand subsurface reservoir behavior and best monitoring technology. To achieve the best storage location as well as injection scenario detail evaluation including geology, geophysics and geomechanics need to done to avoid reservoir or top seal failures, which can cause environmental disaster. There are two possible reservoir candidates, which can be used for injecting CO2 in the Gundih field and surrounding area. Shallow (~1000 m) reservoir sequence consists of medium to thick quartz sandstone of Miocene Ngrayong Formation. The deeper (~2000 m) reservoir sequence consists mainly of carbonate units of Kujung Formation. Traps are mostly structures consist of fault-bounded anticline forming 4-way or 3-way dip closures. Fault-seal analysis suggesting most faults are sealing using SGR (20%). Geomechanics indicate strike-slip stress condition where Shmax>Shmin>Sv and most reservoir are in hydrostatic pressure condition. Overall, site evaluation results suggest that shallow reservoir target which is Ngrayong Formation is more suitable, stable and economic for conducting CCS pilot study.
|Title of host publication||Proceedings of the 12th SEGJ International Symposium|
|Publication status||Published - Nov 20 2015|