A work flow for carbonate rock physics modeling: a log-base methodology

Rock physics modeling plays an important role in determining the character of carbonate reservoirs. Reservoir characterization in carbonate rocks is more complex because it has various types of pores. Pore type analysis is very important for considering the analysis of seismic data and also for considering the proper drilling technique. Pore type is generally estimated using thin section data, but thin section data is not always available. Thus, in this paper we introduce a rock physics modeling workflow in carbonate reservoirs using well log data. The well log data used in this study located in Kujung I Formation, East Java Basin. To get the right elastic property model of carbonate rock, the main thing that needs to be considered is the estimation of the mineral matrix modulus and the aspect ratio with various approaches. By using a modified Kumar and Han (2005) method, the aspect ratio of soft pore, reference pore, and stiff pore are 0.09, 0.177, and 0.506, respectively. The velocity modeling is done by using Kuster-Toks¨oz equation. The results of the elastic properties modeling are close to the actual data. The correlation between the V p Kuster-Toks¨oz and the actual V p are 0.9269. While the correlation between the Vs Kuster-Toks¨oz and the actual Vs are 0.9803.