Publications

Semberah field’s infill drilling activity to increase its recovery has been generally challenging because of limited seismic information to support the reservoir distribution characterization. Stratigraphic model building has been using mainly geological concept and well log analysis while undermines seismic information because of poor quality 2D lines. The best seismic quantitative interpretation uses in Semberah encompass amplitude mapping of extracted post-stack attributes. Semberah asset team recently suggests a new stratigraphic framework consists of isolated distributary sands and active delta switching sequences. The new framework allows seismic forward modeling method to constrain the sand boundaries. The seismic modeling workflow involves building rock physics models, performing synthetic modeling of varying channel facies over its elastic properties. The synthetic PP-reflectivity generation uses Semberah well’s wavelet extraction from Roy-White algorithm extraction which are later varied with several scenarios of fluid, porosity and random noise. The latest volumetric estimation from the integrated modeling produces significant oil and gas resources to justify Semberah further development. Both static model and seismic forward modeling suggest potentially finding wet sands during the SB-27 well drilling activities in July 2019. The well’s location uncertainty has been optimized by moving the well location to a structurally updip position from the existing well UKM-03 to avoid potential water level. A recommendation has also been put forward for the remaining five-well drilling proposals to sharpen the targeted stacked channels around the recommended areas. The seismic forward modeling technique has never been applied as part of the seismic quantitative interpretation method in Semberah, yet such process could be carried out with only 2D seismic lines. The result from seismic forward modeling provides better integration with the geological model and becomes a cost-effective option to optimize area with limited dataset such as Semberah. The updated geocellular model and the seismic forward modeling results have already been used to identify a number of prospect area and would invigorate the future Semberah well drilling proposals.