Abstract:Porosity and saturation are two important parameters for fractured reservoir evaluation. This paper proposes a new method to calculate porosity and saturation in fractured reservoirs using their anisotropic gradient. We first use the equivalent theory to calculate intercept and gradient, then calculate anisotropic gradient, and finally fix one of the two parameters (porosity or saturation) to calculate the other one. The proposed method is provided with application value for the oil field development, although it is impossible to simultaneously invert porosity and saturation of fractures. Model tests show that signal-to-noise ratio of seismic record has a great impact on reflection coefficients, but has little influence on the calculated porosity and saturation, which proves the validity and adaptability of the proposed method.
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