STUDY OF HYDRAULIC FRACTURING STIMULATION AS PROVEN NOVEL TREATMENT IN REVEALING JABUNG OIL CAPACITY

Abstrak

Overall Jabung Block demonstrated considerably high success ratio of finding economic hydrocarbon since operated by PetroChina on 2002. Oil and gas have been produced coupled with more discoveries (Basement, NEB LTAF, and NEB GUF) within the Jabung Block provided more challenging of future hydrocarbon assesment to both tight sand reservoir condition and significant high CO2 content. Exploration phase of NEB area had only assumed oil reservoir potential only developed in the  northern part before oil discovery was ever proven in southern area. As part of continuous exploration effort PetroChina drilled NEB EXT-1 exploration well that located in down-dip of NEB southern area on 2017, which will be a key well to prove the extension of NEB oil rim. As predicted, Drill Stem Test (DST) showed 38 BOPD intermittent oil flowed on 128/64 choke DST-2 from Lower Talang Akar Formation with 0% CO2 content, opening the validity of NEB oil rim extension area. Combining DST result with the pressure build-up analysis conclude the potential zone do not have significant lithological properties or classify as tight reservoir (5 mD permeability; 0.08 (STB/D)/Psia Productivity Index (PI)) but possess the promising formation pressure up to 2314 Psi. Hydraulic fracturing stimulation has been chosen to deal with reservoir properties limitation in NEB EXT-1 well. Integration of geology, geophysical and reservoir modeling data is required to propose the fracturing model. Over than 44 mD permeability appears in DST-2 virgin zone, productivity index increases to 4.10 (STB/D)/Psia and reservoir rate picked to 101.5 BOPD after the course. All in all, this case study provides the way how hydraulic fracturing could succeed to impact tight oil reservoir in NEB Area focusing in NEB EXT1well and how the program will reveal hidden prospect area surround NEB (i.e.: Tandur, Mamora, West Bejo prospect) as part of Jabung upside potential.