Reservoirs declination in Apure State, Southwestern Venezuela, demands a huge technical effort in reservoir modeling when finding drilling opportunities to increase recovery factor and maintain oil production at attractive economical levels. One of these reservoirs, Escandalosa Inferior of La Victoria Oilfield was discovered by LVT-18 in 1991 with 38 MMSTB of STOOIP and in 1998, the last of its four producing wells was closed, reaching a recovery factor of 14%. An Asset Team revised and integrated geophysical, geological, petrophysical and production data to update Esc-Inf static model in 2005. No robust sedimentological model could be built because of cores absence; however, a facies and later a property distribution was designed with the help of well logs, regional knowledge and geostatistics. The resulting static model led to visualize the opportunity to drill a horizontal well in the highest attic of the structure to reactivate the reservoir. STOOIP calculation for this new model yielded a value of 13 MMSTB with 7.8 MMSTB of recoverable reserves and 2.5 MMSTB of remaining reserves, which could be extracted by the new well and finally obtain a recovery factor of about 60%. The dynamic model showed a reaccommodation of fluids due to its 5 years of closure, and certified the current presence of oil in the attic where the well was previously visualized. The prediction made by the simulator for a 5 years scenario, with a production of 650 STBD, highlighted the economical feasibility of drilling this well. Nowadays, the successful well LVT-46H is still active with 2 MSTBD and has accumulated 0.245 MMSTB, since its completion in 2006. These results validate the methodology presented in this work where data integration, the use of geostatistics and reservoir simulation are the main key for reactivating declined reservoirs and maintaining oil production. Introduction La Victoria Oilfield is located 40 Km to the west of Guasdualito Village, Apure State, Southwest of Venezuela and 6 Km to the East of the Colombian - Venezuelan boundary (see Figure 1). Escandalosa Inferior Reservoir, belonging to this oilfield, is a cretaceous unit (1) constituted mainly by massive and consolidated sandstones with a very continuous thickness in the whole oilfield of up to 140 feet, with few intercalations of shales, featuring porosity values between 20 and 25 % and permeability values between 0.5 and 3 darcies (see Figure 2). Escandalosa Inferior Reservoir had been reporting by the end of 90's high water cuts in the only four producing wells since its discovery, which is a contrasting fact in relation with its remaining reserves of 15.8 MMSTB following the official data yielded by the reservoir static model built in 2001. These high water cuts progressively caused the closure of the four producing wells, the last of which was closed in 1998, setting the reservoir to inactive with a recovery factor of only 14%. Under this perspective, no well could be workovered and even less drilled in this reservoir, without an appropriate structural reinterpretation. In 2003, a 3D seismic survey was completely processed and available for interpretation, and this was the starting point of the structural reinterpretation for generating a 3D static model supported by geostatistics techniques, well logs interpretation and the knowledge of regional geology since no robust sedimentological model was available due to core data absence in this reservoir. This new static model would then be used in a reservoir numeric simulation software in order to know the current state of the reservoir in terms of oil saturation after 7 years of inactivity, and in order to forecast the productivity behavior and future profitability of the prospect wells that probably could be highlighted by the static model and could help increase the reservoir recovery factor.
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