## 2 Materials and Methods  
### Earthquake Catalogue  
In order to analyze the 2002, Mw 7.9 Denali; the 2018, Mw 7.9 Kodiak, and the 2018, Mw 7.1 Anchorage earthquake sequences, the United States Geological Survey (USGS) earthquake catalogue [[https://earthquake.usgs.gov/earthquakes/search/](https://earthquake.usgs.gov/earthquakes/search/)]([https://earthquake.usgs.gov/earthquakes/search/](https://earthquake.usgs.gov/earthquakes/search/)) (accessed on 18 December 2021) was used. The spatial distribution of aftershocks during 30 days after each mainshock are shown in Figure 1. The focal mechanisms of the mainshocks were obtained from the USGS website [34; 35; 36]. The 2002 Denali, Alaska, earthquake sequence occurred along the Denali-Totschunda faults which is a right-lateral strike-slip fault system. The Mw 7.9 mainshock nucleated on the Susitma Glacier thrust fault and propagated further along the Denali fault and continued along the Totschunda fault [29]. The parameters of the elliptical region for this aftershock sequence, are given in Table 2 and the sequence for 30-day is depicted in Figure 1a. The plotted fault plane solution for this mainshock in Figure 1a was taken from the the USGS website [34]. Figure 1: Maps of the occurrence of the aftershock sequences generated by the three significant Alaska mainshocks: (**a**) the 2002 Mw 7.9 Denali sequence with \(m_{0}=3.0\); (**b**) the 2018, Mw 7.9 Kodiak sequence with \(m_{0}=3.2\); and (**c**) the 2018 Mw 7.1 Anchorage sequence with \(m_{0}=2.8\). The events during 30 days after each mainshock are plotted. The blue solid circles represent the aftershocks above \(m_{0}\). Black points are all events between magnitude 2.5 and \(m_{0}\). The focal mechanisms of the studied mainshocks are plotted as beach balls. Quaternary faults are plotted as light brown line segments [33]. The 2018 Mw 7.9 Kodiak, Alaska, earthquake took place in the Gulf of Alaska southeast of Kodiak Island. The mainshock location and the focal mechanism reflect a strike-slip faulting system within the shallow lithosphere of the Pacific plate near the subduction zone [37]. In Table 2 the details of the studied sequence for this mainshock are reported. In addition, the earthquake sequence during 30-day after the mainshock occurrence is demonstrated in Figure 1b. The focal mechanism of the 2018 Mw 7.9 Kodiak, Alaska, earthquake suggests a steeply dipping fault either as a right-lateral system that strikes the north-northwest or as a left-lateral fault that strikes west-southwest. The fault plane solution for the mainshock in Figure 1b was obtained from the USGS website [35]. The 2018 Mw 7.1 Anchorage, Alaska, earthquake happened as the result of a normal faulting rupturing north from Anchorage, Alaska. The location and mechanism of the focal mechanism reflect a moderately dipping north-south fault system fault within the subducting Pacific slab [38,39]. Details of the analyzed earthquake sequence are presented in Table 2 and the sequence of 30-day is illustrated in Figure 1c. The indicated moment tensor for this mainshock in Figure 1c was acquired from USGS [36]. For the statistical analysis of seismicity, several time intervals were utilized to estimate properly the parameters of the models describing the evolution and the statistics of the aftershock sequences. For the estimation of the model parameters, the training time interval, \([T_{0},\,T_{e}]\), is considered. In order to properly account for the impact of preceding earthquakes on the earthquake rate, the training time interval is divided into an initial time interval, \([T_{0},\,T_{e}]\), and a target time interval, \([T_{s},\,T_{e}]\). The seismicity parameters are estimated in the target time interval. A forecasting time interval, \([T_{e},\,T_{e}+\Delta T]\) is also considered to analyze the evolution and the statistics of the seismicity.