## 3pAO7. Finite-amplitude sound wave propagation in granular marine sediment with fractal structure.

### Session: Wednesday Afternoon, December 4

### Time: 3:35

**Author: Igor B. Esipov**

**Location: N. Andreev Acoust. Inst., Moscow 117036, Russia**

**Author: Konstantin I. Matveev**

**Location: Univ. of Colorado, Boulder, CO 80303**

**Author: Konstantin A. Naugolnykh**

**Location: N. Andreev Acoust. Inst., Moscow 117036, Russia**

**Abstract:**

The wave energy localization in the process of sound propagation in the
media with fractal structure leads to the frequency dependence of the nonlinear
response. In the low-frequency range, a sound wave, propagated through the
water-saturated granular matter, has a typical attenuation, related to the Biot
theory. In the range of fractal structure, spatial scales oscillations occur as
localized ones. This state of oscillations is known as fractons. The appropriate
spectrum of oscillations is related to the fractal dimension of the studied
media and falls drastically with the frequency. Experiments of finite-amplitude,
wide frequency sound pulse propagation through the sample of cobalt--manganese
crust deposits are analyzed with respect to appropriate computer-simulated
models. Abnormally large sound attenuation at relatively small-amplitude signal
propagation in the frequency range up 0.7 MHz, was shown, while at the large
signal amplitude, the value of the signal attenuation falls and reaches the Biot
frequency pattern. [Work supported by the Russian Basic Research Foundation,
Grant No. 95-02-06353.]

ASA 132nd meeting - Hawaii, December 1996