Study On Fracture Distribution In S625 Buried Hill Reservoir Of Liaohe Oilfield

The block of S625 is a typical limestone of buried hill reservoir. There is big difference between oil well productivity in horizontal and vertical direction during production. After many years of water flooding, the water channeling of oil wells is serious, production rate is declined continuously and reserves are developed very unequally. Due to the complexity of reservoir geometry, lithological diversity, heterogeneity and the unclearness of fracture distribution of S625 buried hill reservoir, the study of remaining oil distribution and remodeling the development method are difficult.The data of logging, well logging, seismic interpretation and core analysis are applied in this paper. Based on fine stratigraphic comparison, the inside structure interpretation, buried hill reservoir logging evaluation technology, and according to core-imaging logging data for statistical analysis of fracture, structural analysis technology is used to identify the reason for fracture-forming mechanism. This paper identified that fractures are controlled by the ancient stress and fault, and the main developed fracture are NE trending fracture & large angle fracture. Hierarchical fracture characteristics are described and the distribution of fracture for buried hill reservoir is studied in this paper.According to the research aforementioned, dynamic production data are used to verify the fracture prediction accuracy and the predict coincidence rate is above 70%. Meanwhile, based on the identification of fracture, the identification criterion of effective reservoir for buried hill reservoir is established and the oil & water layers are re-identified which are the bases to study the distribution of remaining oil and remodel the development method.