| Popis: |
Periodical PBU/PFO surveys have been conducted for monitoring horizontal wells and reservoir pressure maintenance in five-spot water flooding patterns in a giant carbonate reservoir located offshore Abu Dhabi. Although, in the literature, several methods have been proposed to estimate average pressure over a drainage area, none of such methods is applicable to the situation above where a flood pattern is confined with constant pressure boundaries. In this study, we propose a new method of average pressure estimation for a horizontal well in a drainage area associated with constant pressure boundaries. This new method was developed by creating a type curve representing a pressure correction against P* or an extended pressure as if an infinite reservoir existed. Although this method may look similar to the classical MBH theory, we can substantially differentiate the new method from the MBH method since the new method can handle both a horizontal well and a constant pressure boundary while the MBH method assumes a vertical well and a no-flow boundary alone. New pressure correction type curves were generated through intensive numerical simulations modeling a horizontal well in a square and rectangular drainage with a constant pressure boundary condition. The shape factors under a steady state condition were defined and calculated to characterize and differentiate the shape of individual type curves. |
