The Methods to Determine Oil-Bearing Area in Different Types of Reservoirs of Jilin Oilfield

Abstract

Oil-bearing area is one of the key parameters to calculate geological reserves. Different reservoir types will have different methods to determine oil-bearing area. The statistical analysis of 199 proved development blocks in Jilin oilfield indicates that 92 percent of reservoirs are sandstone reservoirs and fault block oil reservoirs. Reservoir types in Jilin oilfield include lithologic reservoir, structural reservoir and structural-lithologic reservoir. According to the reservoir characteristics and regulation of petroleum reserves estimation in Jilin oilfield, the methods to determine oil-bearing area, which is suitable for different types of reservoir in Jilin, have been summed up. For simple anticlinal structural reservoir, drilling test data is used to determine the oil-water boundary. For fault block oil reservoir, the oil boundary can be composed of fault boundary, oil-water boundary and lithologic boundary. For lithologic reservoir, the lithologic reservoir boundary is determined by probability method and the oil-bearing boundary can be determined by extrapolation method, high resolution seismic or calculating line. For structural-lithologic reservoir, the determination of the oil-bearing area boundary can integrate the methods of structural reservoir and lithologic reservoir Key words: Jilin oilfield; Reservoir type; Oil-bearing area; Structural reservoir; Lithologic reservoir