The Waterflooding Dynamic Analysis Of Chang-2Reservoir Of Dongxigou Oilfield

The characters of Chang2layer in Dongxigou oilfield are thin–single, low porosity, lowpermeability, low reservoir pressure and strong heterogeneity. This oilfield mainly appliedopen hole completion, because of depending on the natural energy during the extraction, thepressure dropped rapidly and had a low total output. Since2008, Dongxigou oilfield carriedout overall water injection, the water ratio increased rapidly, however, the change of outputand the waterflood response were not obvious. Therefore, the Dongxigou oilfield is badlyneeded a research for its waterflood technology.Firstly, this paper analyses the reservoir feature of Dongxigou oilfield. Secondly,evaluating the influential factors for waterflooding, analyzing the production history andmaking the study of water ratio up law, output decline law, individual well producing rate,calculating degrees of water drive reserves, volumetric sweep efficiency, and predicting theultimate recovery of Dongxigou oilfield. Finally, introducing the measures for improving theeffect of waterflood development.According to the analysis and research of this paper, the Chang-2reservoir of Dongxigouoilfield is considered as a fluvial reservoir, the pore types are pore-thin throat and in the hole-tiny throat with deeply heterogeneity；for the sake of improving the effect of waterfloodimprovement, it is necessary to perform multiple measures, such as well network adjustmentand water shutoff profile control, to satisfy the need of development.