Seismic-Based Characterization of Baturaja Carbonate at 3-D Topaz Area

Yuliandri, Indra ¹; Usman, Totong K.¹; Panguriseng, Muharram J.¹
(1)Eksploration, PT. PERTAMINA EP, Jakarta, Indonesia.

The Early Miocene Baturaja Formation is one of the principal reservoirs in the 3D Topaz area. The original facies distribution of carbonate reservoir has the tendency for significant horizontal and vertical heterogeneity over short distance, so provide a challenge for seismic interpretation and reservoir characterization. Based on several wells data, carbonate platform of Baturaja Formation at 3D Topaz area shows different lateral facies change, contain evidence of diagenesis, and fracturation process which affect the reservoir quality. Reservoir characterization made from interpolating well data are too simple to predict reservoir propeties accurately, so the seismic data can help reduce uncertainty about rock properties among wells. Seismic facies and geometries interpreted from the attribute analyses and seismic inversion combined with interpretation of the original seismic, cutting-core log data and geological interpretation, allowed to construct robust structural and depositional models of carbonate environments.

The results of the inversion were acoustic impedance and porosity derived from the simple relationship between porosity and acoustic impedance as observed from the well data. The results were used to interpret the facies distribution and to map the porosity distribution. By adding careful hydrocarbon distribution interpretation, the inversion results have been used for locating new wells to drill hydrocarbon.

AAPG Search and Discovery Article #90135©2011 AAPG International Conference and Exhibition, Milan, Italy, 23-26 October 2011.