2005_SEG_Mavko.pdf

A Theoretical Estimate of S-Wave Attenuation in Sediment Gary. Mavko*, Stanford University, Jack Dvorkin, Stanford University and Rock Solid Images, Joel Walls, Rock Solid Images ABSTRACT Some of laboratory and field data (albeit very sparse) indicate that the S-wave attenuation in a sediment sample (a) weakly depends on water saturation and (b) approximately equals the P-wave attenuation at 100% water saturation. These observations are matched by our theoretical model. In this model we assume that (a) the Swave inverse quality factor is related to the shear-modulusversus-frequency dispersion by the same viscoelastic relation as the P-wave inverse quality factor (e.g., the standard linear solid) and (b) the shear-modulus-versusfrequency dispersion is linked to the compressionalmodulus-versus-frequency dispersion.