# Integrated Earthquake Catalog II: The Western Sector of the Russian Arctic
## 4 Conclusions  
This paper describes step by step the procedure for compiling the integrated earthquake catalog for the western sector of the AZRF with a unified magnitude scale (Figure 19). The unification was carried out based on the analysis of ratios of magnitude types in the source catalogs. It should be noted that the obtained catalog, in contrast to the original catalogs, is characterized by the completeness and representativeness of events. The unified catalog is made available to the public at: [[http://www.wdcb.ru/arctic_antarctic/arctic_seism.html](http://www.wdcb.ru/arctic_antarctic/arctic_seism.html)]([http://www.wdcb.ru/arctic_antarctic/arctic_seism.html](http://www.wdcb.ru/arctic_antarctic/arctic_seism.html)), (accessed on 1 June 2023). The integrated earthquake catalog obtained in this paper is intended for a wide range of researchers involved in both the study of the seismic regime of the Arctic and, in general, the seismic hazard assessment [37; 38; 39; 40; 41; 42; 43; 44; 45]. Based on the results obtained in this study, the authors consider it possible to formulate the following conclusions:  
1. Merging data from the GS RAS, Morozov, and the ISC catalogs significantly increased the number of registered events in the western sector of the AZRF (Tables 3 and 6);
2. The modified nearest neighbor method [1] efficiently identifies records in different catalogs that correspond to the same seismic event (Figures 4-8, Table 3). The error rate for duplicate identification in the studied region was found to be 0.2%;
3. Information on explosions and other events that are not tectonic earthquakes, presented in the catalogs of GS RAS and ISC, is incomplete. Approximately 300 such events from the GS RAS catalog (ER_EXP in Table 1) are classified as earthquakes in the ISC catalog, and conversely, about 100 explosions from the ISC catalog are classified as earthquakes in the GS RAS catalogs (Figure 9, Table 3);  
Figure 24: Integrated catalog. Map of spatial variations in the completeness magnitude \(Mc\) for the period 1998–2020. The black dots show the earthquake epicenters, the red line is the level \(Mc=1.8\), the blue line is \(Mc=2.3\). 4. Explosions before 1998 and after 2020 have not been removed (Figure 10). Explosions after 2020 may be removed with the arrival of new data-GS RAS catalogs and reviewed ISC catalog. Identifying and removing explosions that occurred before 1998 is an extremely difficult task beyond the scope of the mathematical methods used in this study;
5. In general, there is no sufficient guarantee that \"non-earthquakes\" have been completely removed from the combined catalog during the period of 1998-2020. However, there are reasons to believe that the number of such events is small and they will not have a significant impact on regional seismicity statistics;
6. In the western sector of the AZRF, there are no \(Mw^{\rm GCMT}\) determinations. Therefore, a direct unification of magnitude to moment magnitude scale was impossible. However, there were a sufficient number of \(mb^{\rm ISC}\) determinations, which are used in ISC practice to obtain proxy-\(Mw\) estimates for earthquakes with \(M<5.0\)[46]. In the eastern sector of the AZRF, the \(Mw^{\rm GCMT}=mb^{\rm ISC}\) ratio is directly confirmed [7]. All magnitude scales were aligned with \(mb^{\rm ISC}\) (Figures 14 and 18), and it was hypothesized that the estimates made could be used as proxy-\(Mw\) in the western sector of the AZRF for regionally strong earthquakes with \(M\geq 3.5\), for the overwhelming majority of which \(mb^{\rm ISC}\) and \(mb^{\rm NEIC}\) determinations are known. Interpreting weaker magnitudes as proxy-\(Mw\) is certainly controversial, since they fall outside the range for which regression relationships are constructed. 7. Unlike the eastern sector of the AZRF, where the overwhelming majority of events had only three types of magnitude estimates (\(Mw^{\rm GCMT}\), \(mb^{\rm ISC}\), and energy class \(k\)), the diversity of magnitude estimates for weak earthquakes in the western sector is very high.