KARAKTERISASI RESERVOIR KARBONAT DI LAPANGAN “ANA”, FORMASI KUJUNG, CEKUNGAN JAWA TIMUR UTARA DENGAN MENGGUNAKAN METODE INVERSI IMPEDANSI AKUSTIK DAN MULTI ATRIBUT

Utomo, Dwi P, Wahyudi

2015 | Skripsi | FMIPA UGM

Reservoir target in ANA field located at North East Java basin, Kujung formation which rocks its formation dominant with carbonate (limestone). Characterization of hydrocarbon reservoir has been done by using inversion and multiatributes method. Integration both of method can expected identify sensitivity of reservoir. If compared with seismic data conventional which only give information lithology, so the result both of this method can give information physics about acoustic impedance, effective porosity, and density for carbonate reservoir. Data used in this study is well log data, seismic data, and geological data were used to completing this research. Model based inversion method was used to proceed this inversion process with a Pre-Stack Time Migration (PSTM) seismic data as the input. Acoustic impedance volume and seismic data were used for multi attributes analysis to produce Effective Porosity volume and Density Volume. An integrated interpretation by using acoustic impedance, Effective Porosity and Density data can be used to identify distribution of reservoir porosity. The result of the interpretation process indicates that the target zone was composed by limestone reefal. The value of acoustic impedance of the limestone more than 21500 (ft/s) (g/cc), the Effective Porosity value is 9-13 Percent and density value 2,3-3,5 gr/cc. The analysis shows that the distribution of reservoir porosity is spread all around the reefal structure.

Kata Kunci : acoustic impendance inversion, effective porosity, density