rp ''= 1/St . (v(r,t) - rp' - Wterminal n)                                                                   
                                                                                                   …. Equation 2 (T. Haszpra and T. Tél, 2011)
where v (r, t) is the flow field, Wterminal is the dimensionless terminal velocity in still fluid, and n is an upward-pointing unit vector. The units of velocity and distance are characteristic velocity units, U and L, respectively. The dimensionless relaxation period of inertial particles exposed to Stokes drag is denoted by the Stokes number (St). Typically, the limit of St0 in (equation 2) indicates finite acceleration only if the parenthesis on the right-hand side disappears, and the large-scale equation of motion for aerosol particles becomes even simpler than before. On the contrary, the inertial effects are minor, but deposition must be considered with a terminal velocity in the vertical direction.
In this paper, we used magnitude spectrum to get the relative intensity of the BH1 frequency channel from HTHH eruption event on 15th January 2022 at 4:12 UTC can be seen in Fig. 1. For charting vibration spectra, logarithmic amplitude scaling is preferable to linear amplitude scaling because it allows for better evaluation of extremely tiny components in a spectrum. Linear amplitude scaling makes the larger components of a spectrum highly visible and easy to analyse, but it might make very small components impossible to perceive. The technique of spectral balancing is used to flatten the frequency content and amplitude spectra of seismic data. This approach can increase vertical resolution in seismic amplitude volumes by revealing narrow channels and visible edges. Following spectral balancing, energy ratio coherence can be applied to both the input data and the spectrally balanced data. Spectral decomposition may also be used to spectrally balanced versions of raw seismic data, allowing equal time slices to be computed from speech component volumes.
To summarise, spectral magnitude is an energy measurement that corresponds with the trace in seismic data. The seismic moment and magnitude can be estimated via spectral analysis as shown in Fig. 1.