摘要 |
A method for identifying a nature of formation contrasts that cause changes in seismic or sonic wave properties in a low-frequency range includes obtaining a selected property of a formation surrounding a borehole, wherein the selected property is at least one selected from the group consisting of a permeability and a fracture density; decomposing seismic signals into a set of instant amplitudes and frequency fields; calculating a plurality of low-frequency attributes characterizing the low-frequency range of the seismic signals; and establishing a correlation between at least one of the plurality of the low-frequency attributes and the selected property of the formation.
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