Figure 7 Magnitude-frequency distribution of the earthquakes in the synthetic catalogs obtained – from the simulation algorithm described in the text using a discretization of 0.5 km x 0.5 km, and two different combinations of the parameters S-R and A-R. The coloured areas represent the observed magnitude distribution obtained for two sections of the CTPI15 catalog. 6.3 Comparison of the synthetic and real catalog for the largest magnitudes Let’s focus our attention on the SFS03 source, the one containing the strongest Cittaducale-Barrea historical earthquake of the whole region (the 1915 Mw 7.1 earthquake; Table 1), as well Marsica as the one with a large slip rate (Table 2) and a short recurrence time (Table 5). We see in Figure 1 that three M 5.5 earthquakes, but no other M 6.0 earthquakes are reported for this SFS. ≥ ≥ Referring to SFS03, the100 kyr synthetic catalog contains 374 M 6.0 earthquakes and 9 M 7.0 ≥ ≥ earthquakes, with a 7.15 maximum magnitude. Therefore, the simulation algorithm would give an expectation of about one earthquake in 10,000 years of magnitude class 7 on the SFS03 source. This simple computation leads us to consider the 1915 Mw7.1 earthquake an extremely rare Marsica phenomenon, unlikely to recur on the same fault system in the next several thousands of years. Another interpretation of this circumstance could be that the Mw7.1 magnitude reported in CPTI15 is overestimated. This interpretation appears consistent also with the maximum magnitude value of 6.7 assigned by the DISS 3.2.0 compilers to this particular source. The presence of the Mw7.1 earthquake in the CPTI15 historical catalog is the main reason Marsica of the discrepancy between the cumulative magnitude distribution of the CPTI15 data and those obtained by the 100 kyr simulation for the whole Central Apennines region, especially for the observations with M 5.0 starting in 1871 (Figure 2). However, taking into account the ≥ uncertainties shown by the error bars of Figure 2, this discrepancy is not quite significant. Moreover, in light of the discussion about the singularity of the 1915 earthquake, made above, this
Figure 7 – Magnitude-frequency distribution of the earthquakes in the synthetic catalogs obtained from the simulation algorithm described in the text using a discretization of 0.5 km x 0.5 km, and two different combinations of the parameters S-R and A-R. The coloured areas represent the observed magnitude distribution obtained for two sections of the CTPI15 catalog. 6.3 Comparison of the synthetic and real catalog for the largest magnitudes Let’s focus our attention on the SFS03 Cittaducale-Barrea source, the one containing the strongest historical earthquake of the whole region (the 1915 Mw 7.1 Marsica earthquake; Table 1), as well as the one with a large slip rate (Table 2) and a short recurrence time (Table 5). We see in Figure 1 that three M ≥ 5.5 earthquakes, but no other M ≥ 6.0 earthquakes are reported for this SFS. Referring to SFS03, the100 kyr synthetic catalog contains 374 M ≥ 6.0 earthquakes and 9 M ≥ 7.0 earthquakes, with a 7.15 maximum magnitude. Therefore, the simulation algorithm would give an expectation of about one earthquake in 10,000 years of magnitude class 7 on the SFS03 source. This simple computation leads us to consider the 1915 Mw7.1 Marsica earthquake an extremely rare phenomenon, unlikely to recur on the same fault system in the next several thousands of years. Another interpretation of this circumstance could be that the Mw7.1 magnitude reported in CPTI15 is overestimated. This interpretation appears consistent also with the maximum magnitude value of 6.7 assigned by the DISS 3.2.0 compilers to this particular source. The presence of the Mw7.1 Marsica earthquake in the CPTI15 historical catalog is the main reason of the discrepancy between the cumulative magnitude distribution of the CPTI15 data and those obtained by the 100 kyr simulation for the whole Central Apennines region, especially for the observations with M ≥ 5.0 starting in 1871 (Figure 2). However, taking into account the uncertainties shown by the error bars of Figure 2, this discrepancy is not quite significant. Moreover, in light of the discussion about the singularity of the 1915 earthquake, made above, this