ABSTRACT
This paper presents an inter-company, multi-disciplinary team effort to evaluate the infill drilling potential in Drill Site 9, Flow Station Two of Prudhoe Bay. The primary focus is on the construction of a 3D, four-component, Todd & Longstaff model for benefit analyses. A four-well drilling program was implemented in January 1993, based on results from stochastic modeling. The benefit estimates were reconciled and reality-checked with surveillance and production data.
Work conducted by Geology, Operations, Drilling, Materials, and Facilities Engineering staff among different companies in the Unit team are also summarized to provide a complete picture of this development drilling planning exercise. Special emphasis is placed upon the effectiveness of multi-disciplinary team work in minimizing costs and managing uncertainties, and the overall efficiency in meeting project deadlines.
In a water-alternating-gas miscible flood, the net recovery of an infill sidewell is estimated to be about 12% of its through-wellbore recovery, dependent on the reservoir description, time at which the sidewell is drilled, flood rate, individual well economic limits and project abandonment timing.
The methodology presented may be applicable in other waterflood/EOR areas of Prudhoe Bay for constructing a screening tool for evaluation of infill drilling opportunities. As long as the simulation results are reality-checked with offset well production, geological and surveillance data, drilling risk can then be significantly minimized with good contingency planning.
