Publications

The waterflood project was established in the Widuri field, Asri Basin, Southeast Sumatra in 2000 and involved three major oil fields as pilots: Widuri, Intan, and Vita. The biggest challenges during water flooding applications are to maintain the well, keep the rate stable, and minimize the declining production. Engineering efforts combined with subsurface integration have been applied to maintain the pressure to keep the oil production stable. The Widuri “H” well is one of the success cases. The well was successfully put back online to produce at a significant oil rate after having been declared as “watered out”. The Widuri “H” was drilled in September, 2007 as part of a water flood management project with 32 feet SSTVD oil and gas pay. The well has been producing for two years from December 2007 with cumulative oil production of 123.8 MBO. In May 2009, the well watered out at 100% water cut. The production profile showed that the water cut suddenly increased one month before completely watering out. An integrated analysis was performed to evaluate the cause and whether this well still had oil potential on the 34-1 sand reservoir. Several evaluations were conducted as follows: • Applied integrated three- (3D) and four-dimensional (4D) seismic to evaluate the subsurface condition. • Deepening reservoir targets on the offset proposal Widuri “A” well. • Building the water distribution map using a 3D geological model. • Remaining reserves evaluation pre and post water out. • Production and injection rate from injector well. • Performing good injection management. • Evaluating the possibility of a watered out well due to the highest water injection rate. The well has been back in production since August 2010. The integration of subsurface and engineering problem-solving ensured that the “water out” well was able to produce again.