Shale oil-gas economical and effective layer section evaluation method

The invention provides a shale oil-gas economical and effective layer section evaluation method. The method comprises the steps of determining evaluation parameters of shale of target layer sections according to obtained logging data and core data, wherein the evaluation parameters include the organic carbon content, the porosity, the formation pressure coefficient, the oil-gas accumulative output impact factor and elastic parameters; subtracting a corresponding cut-off value from each evaluation parameter to obtain a difference value of each evaluation parameter; using points with the difference values, larger than 0, of the evaluation parameters as efficient points; adding the thicknesses of logging points which are continuous efficient points in the target layer sections, and using the added result as the single-layer thickness of the continuous efficient points; determining the shale oil-gas accumulated economical yield minimum thickness; using the layer section with the single-layer thickness of the continuous efficient points larger than or equal to the accumulated economical yield minimum thickness in the target layer section as the shale oil-gas economical and effective layer section. According to the shale oil-gas economical and effective layer section evaluation method, the shale oil-gas economical and effective layer section can be accurately and effectively determined, and therefore the shale oil-gas development benefits are improved.