Although the mechanisms causing seismic wave attenu-ation (1/Q), the inverse of the quality factor, are always fre-quency-dependent, most Q estimation methods are still based on the assumption that Q is constant across frequen-cies. Therefore, existing rock-physics Q models have not been effectively applied to bridge frequency-dependent Q estimations and rock properties such as porosity and fluid saturation. An alternative way of dealing with frequency -de-pendent Q estimation is to use the mechanical response of viscoelastic models in the log spectral ratio method. Never-theless, viscoelastic models are phenomenological models that lack physical meaning resulting in errors in Q estima-tion. Through the process of suitable rock-physics modeling and scaling, a new frequency-dependent Q estimation method, called the two-parameters spectral ratio method, is developed based on the wave-induced gas exsolution and dissolution and differential Kuster-Toksoz approach, appropriate for evaluating attenuation in saturated rocks. Compared with conventional Q estimation methods, our al-gorithm builds a link between rock-physic models, logging, and seismic data, providing more accurate and reliable Q results for better interpretation of subsurface properties.
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