Waterflooding is still the most common method used worldwide for improving oil recovery, either after production by primary mechanisms or at early stages of the field lifetime.

During the waterflooding process, injectivity decline can occur due to rock and fluids characteristics, well geometry, and formation damage caused by fines migration, salt precipitation and by solids and oil particles present in water entrainment. One of the best ways to avoid injectivity decline is the Injection with Fracture Propagation Pressure (IFPP).

In this work a methodology for modeling fracture propagation is presented, as well as the sweep efficiency effects due to IFPP, using an in-house geo-mechanical simulator combined with a commercial reservoir simulator.

The simulations show that the impact on oil recovery due to IFPP can be high, depending on injection pressure, fracture propagation velocity and direction, type of well (vertical or horizontal), well pattern, distance injector-producer and starting time of IFPP. By the other hand, the impact of injectivity loss on the Net Present Value may be high, so that the benefits of injection rate maintenance with IFPP can overcome a possible negative impact on sweep efficiency.

The conclusions point out to the importance of knowing the geo-mechanic reservoir characteristics in order to choose well type, injection pattern and well spacing, so that the benefits of IFPP can be completely achieved.

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