A New Method to Evaluate Tight Oil Reservoir of Chang7 Member in Zhidan Area

At present, tight oil reservoir is a hot spot in the field of oil and gas development, and the effective development of such reservoir needs reservoir evaluation as a guide. Based on the experimental research on the core of tight oil reservoir of Chang7 member in Zhidan area, combined with the method of statistics and numerical simulation, eight parameters of “sand thickness, crude oil viscosity, main throat radius, starting pressure gradient, clay mineral content, rock brittleness index, percentage of movable fluid and reservoir pressure coefficient” are selected, and then, the new method of tight oil reservoir evaluation is obtained after normalizing the each parameter. Through this method, the tight oil reservoir of Chang7 member in Zhidan area can be divided into Class I, Class II and Class III, of which Class I and Class II reservoirs currently have certain development value. When development this kind of tight oil reservoir, large-scale hydraulic fracturing is required, which may affect or destroy the existing original forest protection area, water resource protection area and farmland. Therefore, after considering the environmental safety factors, the reservoir is classified and evaluated, and the development block is selected.