## 3 Description of the Obtained Results: Processing and Interpretation  
Table 1 shows some data on the radiation stations: the first column contains the radiation station number; the second column contains the radiation start and end time, UTC; the third column contains the latitudes of the radiation's start and end; the fourth column contains the longitudes of the radiation's start and end; the fifth column contains the azimuth of the laser strainmeter axis at the radiation's start and end; the sixth column contains the distance from the radiation point to the laser strainmeter at the radiation's start and end; and the seventh column shows the average sea depth at the radiation station according to the echo sounder (except for station 4, determined from the map). For further processing, we used experimental data obtained on the 52.5-m laser strainmeter. Processing was carried out using standard spectral methods; with their help we determined the amplitude of the registered signal at the radiation frequency during operation of the low-frequency hydroacoustic radiator at each station. Figure 4 shows fragments of spectra with the maxima at a radiation frequency of 22 Hz. \begin{table}
\begin{tabular}{c c c c c c c} \hline \multirow{2}{*}{**Station**} & **21.07.2024**, & **Latitude,** & **Longitude,** & **Azimuth,** & **Distance,** & **Depth,** \\  & **UTC** & **N** & **E** & **deg** & **m** & **m** \\ \hline \multirow{3}{*}{1} & Start—04:56 & 42\({}^{\circ}\)32.214 & 131\({}^{\circ}\)10.243 & 166.56 & 4926 & \multirow{3}{*}{52} \\  & End—05:07 & 42\({}^{\circ}\)32.318 & 131\({}^{\circ}\)10.256 & 165.98 & 4742 & \\ \multirow{3}{*}{2} & Start—06:29 & 42\({}^{\circ}\)27.915 & 131\({}^{\circ}\)11.728 & 166.09 & 13,146 & \\  & End—06:38 & 42\({}^{\circ}\)27.995 & 131\({}^{\circ}\)11.710 & 165.99 & 12,996 & \\ \multirow{3}{*}{3} & Start—08:04 & 42\({}^{\circ}\)23.222 & 131\({}^{\circ}\)12.650 & 168.34 & 21,908 & \\  & End—08:13 & 42\({}^{\circ}\)23.368 & 131\({}^{\circ}\)12.641 & 168.24 & 21,641 & \\ \multirow{3}{*}{4} & Start—18:06 & 42\({}^{\circ}\)18.238 & 131\({}^{\circ}\)20.468 & 153.31 & 34,220 & \\  & End—18:15 & 42\({}^{\circ}\)18.275 & 131\({}^{\circ}\)20.518 & 153.21 & 34,189 & \\ \hline \end{tabular}
\end{table} 
Table 1: Data on radiation stations. Figure 3: The 52.5-meter laser strainmeter. (**a**) Central interference unit, (**b**) laser beam guide. In our further calculations, in accordance with [15], we assume that the laser strainmeter records a Rayleigh-type surface wave formed as a result of the transformation of a hydroacoustic wave at the \"water-bottom\" boundary and propagating along \"the Earth's crust-air\" boundary. We use the following data in our calculations: \(\rho_{w}=1000\) kg/m\({}^{3}\) (water density), \(c_{w}=1500\) m/s (sound speed in water), \(\rho_{b}=2100\) kg/m\({}^{3}\) (density of the rocks of the upper layer of the Earth's crust), \(c_{b}=2300\) m/s (Rayleigh-type wave speed at \"the Earth's crust-air\" boundary), \(f=22\) Hz (frequency), \(\theta\) is the angle between the laser strainmeter axis and the \"radiator-stations 1, 2, 3, 4\" line, \(\omega=2\pi f\), and \(R\) is the average distance from the radiation point to the nearest point of the laser strainmeter. For a Rayleigh wave, the amplitude decays exponentially with the depth of the Earth's crust. The elastic energy density of Rayleigh-type surface waves can be calculated using the following equation [15]:  
\[E_{r}=\int_{0}^{\lambda_{b}}\frac{\rho_{b}\omega^{2}u^{2}\mathrm{exp}(-4\pi z /\lambda_{b})}{2\mathrm{cos}(\theta)^{2}}dz, \tag{1}\]  
where \(u\) is the amplitude of the displacement at the frequency of the radiated signal, and \(\lambda_{b}\) is the Rayleigh wavelength at the \"air-the Earth's crust\" boundary, equal to 104.5 m.  
In this work, it is fundamentally important to determine what laws will be used to propagate the energy from the radiation source to the receiving point.