Flooded Layer Log Interpretation Methods

China is one of the biggest countries in continental facies oilfield production in the world, which ninety-five percent of crude production coming from the continental facies oil layers. Because of decades of water-flooding development, most oil fields have been in the water breakthrough stages of multi-well, multiplayer and multi-aspect. The average water cut has exceed 80%. Oil wells whose water cut is over 60% have been more than half of the total oil wells. Most of oil fields in the world have already stepped into the stages of high water-cut and production decline. This will lead to more and more difficult oil-field development. In the face of such situation, how to improve the oil field recovery, excavate remaining reserves and predict the distribution of oil remaining accurately have been a very important and under-resolved issue for our high water-cut oil fields which are at the new exploitation stage.This dissertation is based on the spread collection and absorption of log interpretation technologies on the water-flooded zones that come from civil and abroad. A set of fairly complete evaluation techniques for water-flooded zones is formed ranging from affecting factors, watering mechanisms, routine logging data, qualitative and quantitative explanation technologies of water-flooded zones to its comprehensive evaluation technologies. This set of technologies was combined with numerical simulation with the remaining oil saturations calculated by logging interpretation of water-flooded zones to modify those resulted by numerical simulation in order to improve the simulation model. Thus, the adaptability of simulation model to the actual reservoir situation is improved with enhancement of numerical simulation precise for remaining oil saturation prediction.Based on the log interpretation evaluation methods of water-flooded zone, in this article, the wells in Guan979 fault block were taken as examples. The remaining oil saturation which come from numerical simulation was modified by that from the water-flooded zone's log interpretation. Combined these practical production data, the application in oil field has shown that this method is more accurate and reliable. It will play an important role in the distribution analysis of remaining oil saturation, further pattern modification, location of infill wells, adjustment of injection-production relation, profile control and exclusion of water. This method has better popularization and application value.