Reservoir Characterization Using Acoustic Impedance Inversion Method and Multiattribute Analysis in the “X” Field, Central Sumatra Basin

Abstract

Reservoir characterization is the process of analyzing and describing reservoir properties using well log data and seismic data, which is common for oil and gas drilling purposes. The location of the study is in the “X” field in the Bekasap Formation of Central Sumatra Basin Area, one of the most productive oil and gas basin in Indonesia. This study will examine the relationship between acoustic impedance (AI) inversion, effective porosity (PHIE), and shale volume (Vshale) through a multi-attribute process to map the distribution of reservoir porosity in the target area and recommend prospective areas for further oil and gas well development based on the results of acoustic impedance and multi-attribute analysis. The acoustic impedance value range of 15000-18000 (g/cc)*(ft/s) is indicated as sand lithology based on crossplot analysis and seismic inversion result. The possible target area to recommend for further drilling with porosity 18-21%, and Vshale <50%. Porosity is dominantly good in the northeast and southwest areas. For further development well drilling suggestions, it is best to do it in areas with closure, slightly low impedance, medium to high porosity, and low Vshale value in the southwest, northeast, and southeast areas of the field.