Over the past 50 years, a sequence of destructive earthquakes, such as the 1968 (Mw 7.2), 1996 Tonimi (Mw 7.9), and 2018 Palu (Mw 7.5) earthquakes, occurred on the Palu-Koro strike-slip fault and the Minahassa Megathrust, which caused catastrophic disasters in Central Sulawesi, Indonesia. To explore the relationship between fault interaction and earthquake migration in this target area, we simulated the Coulomb stress change (ΔCFS) caused by 13 historical large earthquakes (M ≥ 6.0) since 1968. We show that the 1968 earthquake (Mw 7.2) on the Palu-Koro Fault promoted the 1996 earthquake sequence (Mw 7.9, Mw 6.6, and Mw 7.0) on the Minahassa Megathrust by transferring positive stress to its western edge with a maximum ΔCFS value of 124 kPa before 1996. Consequently, the 1996 earthquake (Mw 7.9) promoted six large earthquakes (M ≥ 6.0) including the 2018 Palu earthquake (Mw 7.5) on the Palu-Koro Fault between 1998 and 2020 via stress loading over the entire Palu-Koro Fault with a maximum ΔCFS value of 76 kPa. Via a positive feedback, these six earthquakes have increased stress at the western edge of the Minahassa Megathrust with a maximum ΔCFS value of 265 kPa up to 2020, resulting in increased seismic and consequent tsunami hazards in this region. Based on these risks, close attention should be paid to the future seismic hazards in Central Sulawesi. These findings suggest that the Palu-Koro Fault and the Minahassa Megathrust constitute a coupled fault system in which seismicity in either fault might bring the other closer to failure. Our results provide new insights into the causes of earthquake generation, migration, and hazard estimation in Central Sulawesi, and provide a basis for understanding stress transfer and seismic activity in strike-slip and thrust fault systems globally.

在过去的 50 年里，Palu-Koro 走滑断层和 Minahassa 发生了一系列破坏性地震，例如 1968 年（Mw 7.2）、1996 年 Tonimi（Mw 7.9）和 2018 年 Palu（Mw 7.5）地震大推力，在印度尼西亚中苏拉威西岛造成了灾难性的灾难。为了探索该目标区域断层相互作用与地震迁移之间的关系，我们模拟了自 1968 年以来 13 次历史大地震（M ≥ 6.0）引起的库仑应力变化（ΔCFS）。我们表明，1968 年的地震（Mw 7.2）在Palu-Koro 断层通过将正应力转移到其西部边缘，在 1996 年之前以 124 kPa 的最大 ΔCFS 值促进了 Minahassa 大逆断层的 1996 年地震序列（Mw 7.9、Mw 6.6 和 Mw 7.0）。因此，1996 年地震（Mw 7.9）促进了六次大地震（M≥6。0) 包括 1998 年至 2020 年间帕卢-科罗断层上的 2018 年帕卢地震 (Mw 7.5)，通过整个帕卢-科罗断层的应力加载，最大 ΔCFS 值为 76 kPa。通过正反馈，这六次地震增加了米纳哈萨大逆冲断层西部边缘的应力，到 2020 年最大 ΔCFS 值为 265 kPa，导致该地区地震和随之而来的海啸灾害增加。基于这些风险，应密切关注苏拉威西中部未来的地震灾害。这些发现表明，Palu-Koro 断层和 Minahassa 大逆断层构成了一个耦合断层系统，其中任一断层的地震活动都可能使另一个断层更接近失效。我们的研究结果为中苏拉威西省地震产生、迁移和灾害估计的原因提供了新的见解，