The sequence
Newest first.
- 4.7150 km SE of Petropavlovsk-Kamchatsky, Russia16 km SE of the mainshock2 weeks ago· 10.0 km deep
- 4.5Off east coast of Kamchatka35 km NW of the mainshock2 weeks ago· 40.0 km deep
- 4.2Off east coast of Kamchatka31 km ESE of the mainshock2 weeks ago· 20.0 km deep
- 4.5165 km SE of Vilyuchinsk, Russia46 km S of the mainshock2 weeks ago· 10.0 km deep
- 4.5167 km SE of Petropavlovsk-Kamchatsky, Russia41 km S of the mainshock3 weeks ago· 10.0 km deep
- 5.1169 km SE of Petropavlovsk-Kamchatsky, Russia35 km ESE of the mainshock3 weeks ago· 10.0 km deep
- 4.9130 km SE of Petropavlovsk-Kamchatsky, Russia9 km NNE of the mainshock3 weeks ago· 36.7 km deep
- 4.6156 km SE of Petropavlovsk-Kamchatsky, Russia28 km E of the mainshock3 weeks ago· 25.0 km deep
- 4.9143 km SE of Petropavlovsk-Kamchatsky, Russia14 km ENE of the mainshock3 weeks ago· 15.6 km deep
How the rupture zone is measured
An aftershock is a smaller earthquake triggered as the crust settles around the fault that ruptured. They cluster along that rupture, so the area worth searching scales with the size of the mainshock rather than being a fixed radius.
The 50 km zone above comes from the Wells & Coppersmith (1994) rupture-length relation, doubled because aftershocks routinely extend about one rupture length beyond each end of the fault, then floored at 50 km and capped at 400 km. Anything outside it is counted as separate regional seismicity, not part of this sequence.
Aftershocks are most frequent in the hours right after the mainshock and taper off over days to months. A quiet day does not mean the sequence has ended.
Data from USGS, EMSC and partner agencies. Magnitudes and locations are preliminary and may be revised.