Sound Propagation in Shallow Water with an Inhomogeneous GAS-Saturated Bottom

Horizontal Refraction of Acoustic Waves in Shallow-Water Waveguides Due to an Inhomogeneous Bottom Structure

“…Although the horizontal refraction has been studied extensively in different environments, there is one more possible scenario that needs to be examined. The scenario suggests the presence of volume inhomogeneities in the upper layer of bottom sediments [11]. Probably, the first mention of this factor is given by Ballard et al in [12].…”

“…An example of a shallow-water waveguide with an inhomogeneous bottom and almost constant water depth is presented in Figure 5, which shows the sound speed structure in one of the regions of the Kara Sea. This complicated range-and depth-dependent structure is obtained by the velocity analysis of 3-D seismic survey data [11]. To study three-dimensional acoustic effects, we choose a rectangular area of the bottom, marked in Figure 5a by the dashed ellipse and shown separately in Figure 5b.…”

“…The existence of such zones can be explained by the presence of gas-saturated or water-saturated silty sediments. The bottom density ρ b is assumed to be constant and equal to 1850 kg/m 3 , which is supported by the core sample analysis results [11]. Due to the lack of information on the sound attenuation coefficient in the seabed, its value is taken equal to 0.33 dB/λ.…”

“…A realistic model, based on the velocity analysis of 3-D seismic survey data from the Kara Sea [11].…”

Average Intensity of Low-Frequency Sound and Its Fluctuations in a Shallow Sea with a Range-Dependent Random Impedance of the Liquid Bottom

“…From open sources, only a few works are known, devoted to the propagation of acoustic signals in the shallow Arctic seas adjacent to the land. Thus, in articles [9,10], in a deterministic formulation, the propagation of low-frequency sound (hundreds of hertz) for several short paths (5 km long) of the Kara Sea shelf with an inhomogeneous bottom is considered. From an acoustic point of view, sound propagation in the Arctic shelf waters occurs under conditions of a shallow waveguide with a nearly uniform distribution of sound velocity over depth and very diverse properties of bottom sediments.…”