ACOUSTIC PROPERTIES OF FINE-GRAINED SEDIMENTS FROM EMERALD BASIN - TOWARD AN INVERSION FOR PHYSICAL-PROPERTIES USING THE BIOT-STOLL MODEL

Acoustic data from two long cores, comprising marine clays and silts t aken from Emerald Basin off Nova Scotia, are presented. High-resolutio n measurements of compressional wave velocity, attenuation, and power law exponent are made using ultrasonic frequencies between 100 to 1000 kHz. The observed values of the frequency dependence of attenuation s uggest that a nonconstant Q mechanism is needed to explain these data, and Biot-Stoll theory is used to model the experimental results. An i nversion scheme is used to constrain physical parameters in the Biot-S toll dispersion relation. The inversion shows that there is a restrict ed range of permeability and grain size. By assigning reasonable value s for grain size in the inversion, the Biot-Stoll model predicts uniqu e values for the permeability and frame bulk modulus that agree well w ith estimates made by other means.