Compressional(P)-wave attenuation, shear(S)-wave attenuation, and shear(S)-wave velocity measurements, compiled for fine-grained, unconsolidated sediments, show trends that do not support empirical relationships [Hamilton, J. Acoust. Soc. Am. 68, 1313–1340 (1980); in Acoustics and Ocean Bottom (F. A. S. E. Specialize Conf., Madrid, 1987)] commonly used for geoacoustic modeling. The exception is compressional-wave attenuation data, from 10 Hz to 500 kHz, that essentially follow a frequency dependence of f1 (±2 standard deviations). P-wave attenuation with depth is difficult, if not impossible, to predict given the variability in the data. Examination of several attenuation/depth profiles indicates that those of Mitchell and Focke [J. Acoust. Soc. Am. 67, 1582–1589 (1980)] may be the best choice for predicting P-wave attenuation with depth at the present time. The assumption that S-wave and P-wave attenuations are proportional [Hamilton, J. Acoust. Soc. Am. 60, 334–338 (1976c); in Acoustics and Ocean Bottom (F. A. S. E. Specialize Conf., Madrid, 1987)] is not supported by the data. S-wave attenuations calculated from effective stress mimmick the data, however, suggesting this as a better method for predicting S-wave attenuation with depth. S-wave velocity/depth profiles fall into high- and low-velocity groups that (1) reflect gross differences in sediment texture, and (2) demonstrate the importance of sediment characterization in order to select an appropriate velocity/depth function.
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Frederick A. Bowles (1997) studied this question.