## 3 Results and Discussion
### Intensity of ENPEMF at Different Distances from the Epicenter  
It is important for the reliable identification of seismogenic effects in a VLF record to exclude the disturbances caused by magnetic storms. This is why our task was also to check for the possible influence of the geomagnetic storm, which happened on 3 March  
Figure 3: The data on geomagnetic conditions at the beginning of March 2024, as given on the website [35] (**top**), and comparison between geomagnetic index \(Ap\) and ENPEMF intensity registered during the period preceding the earthquake on 4 March 2024 (**bottom**). The time of the earthquake (\(EQ\)) is marked in the lower plots with solid vertical lines.  
2024 and preceded the earthquake, in addition to investigating the diurnal periodicity of the VLF signal.  
A comparative analysis was made of the results of ENPEMF monitoring synchronously obtained with the recorders of the same MGR-02-16 type but situated in different locations: at Geophysical Observatory near Almaty, Kazakhstan (\(f=7.5\) kHz and \(10\) kHz), and at the points Kireyevsk (\(f=17.5\) kHz) and Sarapul (\(f=17.5\) kHz) in Russia. At all stations, the magnetic antennas of the MGR-02-16 recorder were set both north-south (\(H1\)-component) and East-West (\(H2\)-component). The mutual disposition of the registration points is plotted in Figure 4. The Russian MGR-02-16 registry data, with hourly time resolution, were provided by the Institute of Monitoring of Climatic and Ecological Systems, Siberian Branch of the Russian Academy of Sciences, Tomsk.  
It was assumed that in the case of global influence from the side of geomagnetic disturbance some response in VLF variation would be registered simultaneously at different points, regardless of their position relative to the earthquake epicenter. Thus, the distance from the points Sarapul (\(56.466^{\circ}\) N, \(53.800^{\circ}\) E), Kireyevsk (\(56.367^{\circ}\) N, \(84.087^{\circ}\) E), and Geophysical Observatory (\(43.042^{\circ}\) N, \(76.944^{\circ}\) E) to the epicenter equals, correspondingly, \(2224\) km, \(1573\) km, and \(12.2\) km. The time series of ENPEMF intensity registered at various epicentral distances before the 4 March 2024 \(M6.1\) earthquake are plotted in Figure 5.  
As discussed above, the distinct burst of ENPEMF intensity was registered at the Geophysical Observatory near Almaty two days previously to the main shock, when the ferrite antenna of the north-south recording channel was pointing to the epicenter of the earthquake, and due to favorable chance, the epicenter was only \(12\) km apart from the measuring equipment. At the peak of the burst, the counting rate of ENPEMF signals was almost five times above its background.  
The prominent burst of ENPEMF detected at the Geophysical Observatory with the north-south oriented antenna is clearly seen in the upper plot of Figure 5. However, the ENPEMF intensities measured in the same north-south registration channel at both remote sites, Sarapul and Kireyevsk, remained at background level.  
As seen in the bottom panel of Figure 5, in the case of East-West antenna orientation, any increase in ENPEMF before the earthquake was not observed in all registration points. This confirms that the magnetic storm of level \(G1\), which occurred on 3 March 2024, practically had no effect on the ENPEMF intensity. Also, it follows from the data presented that any response in a variation of VLF electromagnetic signals to the process of earthquake preparation should be expected only at a short distance and with the favorable orientation of the receiving antenna towards the epicenter.  
Figure 4: The mutual disposition scheme of the MGR-02-16 devices installed in Sarapul and Kireyevsk (Russia) and at Geophysical Observatory near Almaty (Kazakhstan).