For stress-sensitive fractured reservoirs, the decrease of seepage ability is inevitable due to reduction of pore volume caused by formation pressure drop in the process of development. How to effectively restrain the influence of it on the development effectiveness and ultimate recovery is the key to developing fractured reservoir development strategies. This paper takes a fractured reservoir in Bohai Oilfield as an example to study the effects of stress sensitivity on reasonable water-flooding time and formation pressure level. The results show that without consideration of stress sensitivity, the reasonable water-flooding time was when the formation pressure dropped to saturation pressure, while with consideration of stress sensitivity, it was determined by the degree of stress sensitivity. When the retention rate of permeability was above 80% at reservoir saturation pressure, the reasonable waterflooding time was also when the formation pressure dropped to saturation pressure. Otherwise, water-flooding must be carried out at original reservoir pressure. Meanwhile, the formation pressure for reasonable water-flooding time should be kept constant, or slightly elevated with consideration of subsequent developing measures and comprehensive adjustment.
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