## 4 Results
### Results of Coulomb Failure Stress Changes
Near the epicenter of this earthquake, where the \(\Delta CFS\) is higher than 1 bar, the average value reached about 5.4 bar. A significant area of increased Coulomb failure stress was identified in proximity to the source, oriented along the NE-SW direction, although a smaller region of negative \(\Delta CFS\) values was also present nearby, with an average of about \(-\)0.44 bar. Figure 3b shows the \(\Delta CFS\) resulting from four earthquakes with magnitudes exceeding 6 \(M\)w that occurred in 2023. Notably, the seismic events with magnitudes of 7.7 \(M\)w and 7.6 \(M\)w induce significantly larger ranges of \(\Delta CFS\), extending down to depths of 100 km. It \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Date** & **Latitude (\({}^{\circ}\)N)** & **Longitude (\({}^{\circ}\)E)** & **Depth (km)** & **Magnitude (Mw)** & **Strike (\({}^{\circ}\))** & **Dip (\({}^{\circ}\))** & **Rake (\({}^{\circ}\))** \\ \hline
05-05-1986 & 37.72 & 37.70 & 15.0 & 6.0 & 215.9670 & 81.8935 & 105.2100 \\
27-06-1998 & 36.87 & 35.58 & 29.5 & 6.2 & 168.6750 & 53.4500 & 68.4607 \\
01-05-2003 & 39.04 & 40.53 & 15.0 & 6.3 & 43.6277 & 35.118 & 119.0660 \\
24-01-2020 & 38.36 & 39.06 & 8.1 & 6.8 & 248.0000 & 76.0000 & 1.0000 \\
06-02-2023 & 37.29 & 37.04 & 8.6 & 7.7 & 233.0000 & 74.0000 & 18.0000 \\
06-02-2023 & 37.30 & 36.92 & 6.2 & 6.6 & 186.3580 & 42.2270 & \(-\)30.5910 \\
06-02-2023 & 38.09 & 37.24 & 7.0 & 7.6 & 89.7601 & 84.2631 & 17.0882 \\
20-02-2023 & 36.04 & 36.02 & 21.7 & 6.4 & 214.0000 & 57.0000 & \(-\)44.0000 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Seismic information is used to calculate Coulomb stress changes. Figure 3: Plot of Coulomb stress changes. (**a**) \(\Delta CFS\) generated by earthquakes (\(\geq\)6 \(M\)w) occurring in 1986–2020 (depth = 10 km); (**b**) \(\Delta CFS\) generated by earthquakes (\(\geq\)6 \(M\)w) occurring in 2023 (depth = 10 km); (**c**) \(\Delta CFS\) generated by earthquakes (\(\geq\)6 \(M\)w) occurring in 1986–2023 (depth = 10 km). is also important to notice that the \(\Delta CFS\) produced close to the A-end primarily serves to prevent further earthquakes from occurring within the AB vertical plane. The \(\Delta CFS\) values are very high in the 200 km long range along the AB plane close to the 7.7 \(M\)w event, with a mean value of 3.77 bar, which is similar to the 3 bar calculated by [PERSON] et al. [65]. This suggests that the 7.7 \(M\)w earthquake triggered the 7.6 \(M\)w event. The average \(\Delta CFS\) value induced by the 7.7 \(M\)w and the 7.6 \(M\)w earthquakes in the study region reached 4.95 bar at 10 km depth. In the northwest of the study area, there is an area of negative \(\Delta CFS\) with a mean value of \(-\)0.25 bar. The frequency of seismic activity in this region will decrease in the future, as suggested by [PERSON] et al. [65]. There is also a small area of negative \(\Delta CFS\) in the AB vertical plane near the B side with a mean value of -0.52 bar. Figure 3c shows the \(\Delta\)CFS generated by eight earthquakes greater than 6 \(M\)w from 1986 to 2023 together. The 6.3 \(M\)w earthquake in 2003 does not show a significant difference compared to Figure 4a because its source is far from the other events. The 6.2 \(M\)w earthquake in 1998 and the 6.8 \(M\)w earthquake in 2020 showed a more pronounced difference than the separate effects. In the plan view at a 10 km depth, the seismic source of the 6.2 \(M\)w event in 1998 affected the northwest region to a greater extent than when the event acted alone. A zone of Coulomb stress decrease occurs to the west of the epicenter of the 2020 6.8 \(M\)w event under joint action compared to separate effects. The extent of the decrease in Coulomb stress at the northeast of the epicenter is reduced, and the extent of Coulomb stress increase is extended.