During production in a naturally fractured reservoir with natural water influx, under certain flow conditions an imbalance can be generated between gravity and viscous forces within the fracture system. This phenomenon is characterized by the gradual growth of a cone of water in the vertical and radial directions. When the radial growth of the cone base at the oil-water contact reaches the drainage radius, the cone of water reaches its maximum height. After this, the oil-water interface advances without suffering deformation in the pseudo stationary regime. However, when this interface is a short distance from the bottom of the completion interval, the movement of the oil-water interface accelerates and water flows into the well. This phenomenon may shorten the well’s life due to the complexity of oil-water separation offshore and resulting increases in operating costs. In many of the Cretaceous formations of the offshore Mexico Bay of Campeche, oil recovery is limited at the top by the presence of a gas-oil contact and at the bottom by an oil-water contact. To recover the remaining hydrocarbon reservoirs it is necessary to: (1) define the optimal operating range which should be established for each well to delay water and gas breakthrough and (2) to schedule the necessary infrastructure to handle high production rates of water and gas as the field matures. The objectives of this work are to: Model in detail the water coning in the porous fracture system using a fine radial grid, with one meter thick layers concentric around the well, and 2 inches thick layers in the annulus, with and without cement. Obtain an equation to determine the maximum height of water coning, the time it takes to form the cone, and the well shut-in time necessary to undo or “heal” the water cone.
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