QI Workflow to Identify Sweet Spots in the Tight Amin Gas Play in North Oman

As conventional hydrocarbon plays have become more mature, Petroleum Development Oman LLC (PDO) is increasingly focusing towards tight plays. The Amin reservoir is such a play and consists of alluvial sandstone reservoir with high net-to-gross but low porosity and permeability. One of the wells within the area of interest has encountered high overpressures with good porosity in the Amin reservoir and triggered a quantitative interpretation study to identify sweet spots for drilling and to map out fracture networks at target level. This study is split into two sections: the first part consists of a conventional deterministic AVO inversion and the second part describes the application and interpretation of the near offset Ruger equation and of a 3D simultaneous azimuthal inversion. The outcome from part one resulted into a predictive porosity map, which was confirmed by an additional well. Hence, the porosity map has been included in the static model to guide the porosity distribution. The results from the second part are encouraging but qualitative and in addition confirm the findings in surrounding wells. However, more calibration as well as production data is required to accomplish a more quantitative interpretation of these computed volumes. Later this year another well will be drilled.