Analysis on Preferred Flowing Path in Shallow Water Delta Front Based on Reservoir Architecture

The shallow water delta reservoir in South Wen 79 Block is in the stage of high water-cut stages, and is still on the rise. The degree of recovery is low, preferred flowing path is developed and surplus oil is generally distributed with local enrichment (Zhang, 2009). The potential of surplus oil is considerable, while the difficulty is also great. And the basis of effective tapping for remaining oil is to figure out the regularities of distribution. However, the precondition is the identification of preferred flowing path and the effective control for the movement of fluid (Gong et al., 2014). Therefore, it is urgent to identify the preferred flowing path of the Es22 in South Wen 79 Block. With many years of waterflooding on sandstone reservoir, the appearance of preferred flowing path increased the heterogeneity of reservoir, resulting in a large number of invalid circulations of injected water (Zhang et al., 2013). Thus overwhelmingly reducing the availability of water injection rate, reducing the water flooding volume as well as increasing difficulty of reservoir development. With the increasing rate of water content in reservoir, water-oil ratio increases sharply and the recovery factors reduce. Meanwhile, a series of problems such as sewage treatment are brought forward (Sun, 2015). With the investment and cost of oilfield development increasing, the economic and social benefits are becoming worse. Consequently, the identification of preferred flowing path is the key to reduce the adverse effects on the oilfield development with the premise and foundation of application for the plugging and modification technology (Yin et al., 2014). *