Systematic Detection of Short‐Term Slow Slip Events in Southcentral Alaska

• Main Authors: Okada, Yutaro, Nishimura, Takuya
• Other Authors: 岡田, 悠太郎, 西村, 卓也
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Geophysical Union (AGU) 2023
• Subjects: short-term slow slip event; southcentral Alaska; Yakutat; Alaska
• Online Access: http://hdl.handle.net/2433/286212

Slow slip events (SSEs) are important for the slip budget along a megathrust fault. Although the recurrence of weeks-long short-term SSEs (S-SSEs) in southcentral Alaska has been suggested, a large amount of noise prevented us from detecting discrete events. We applied a systematic detection method to Global Navigation Satellite System data and detected 31 S-SSEs during the 14-year analysis period. The events mainly occurred at a depth from 35 to 45 km at a down-dip extension of the 1964 Alaska earthquake, and the active clusters correlated with the region of the subducting Yakutat microplate. A large cumulative slip of S-SSEs indicated a significant contribution to stress transfer along the plate interface, and its source area spatially coincided with that of the long-term SSEs and the afterslip of the 1964 earthquake. Large and recurrent S-SSEs are key phenomena for understanding interplate slip kinematics in this region.