Reviewed by USGSRussia105y ago
M5.9 earthquake 228 km ENE of Petropavlovsk-Kamchatsky, Russia
Sunday, February 18, 1923, 23:39:40 UTC · 53.828°N, 161.817°E
A magnitude 5.9 earthquake struck 228 km ENE of Petropavlovsk-Kamchatsky, Russia on Sunday, February 18, 1923, 23:39:40 UTC, at a depth of 35.0 km (shallow). It is the strongest earthquake within 300 km since an M6.5 on February 12, 1923.
- Magnitude
- 5.9
- Moderate · mw
- Depth
- 35 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 75 km aftershock search area
In context
How big was it, and why here?
Energy released
11 kilotons of TNT
That is about the energy of the Hiroshima bomb. It released about 23 times the energy of a magnitude 5.0.
Tectonic setting
68 km
from the nearest mapped plate boundary, between the Okhotsk and Pacific plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
35 km
Shallow earthquakes (under 70 km) produce the strongest surface shaking for their size, so they are the ones most likely to cause damage near the epicenter.
Did You Feel It?
Where it was felt
No “Did You Feel It?” reports have been published for this event yet. If you felt it, you can add your report on the USGS website.
I felt it — report to USGS ↗USGS PAGER estimate
Who was exposed to shaking
USGS publishes PAGER impact estimates for significant earthquakes, usually within an hour. No PAGER estimate is available for this event.
After the main event
Aftershocks within 75 km
USGS lists 1 M2.5+ earthquake within 75 km in the following 30 days; the largest was M5.8 on February 21, 1923. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 25 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.41923 Kamchatka, Russia EarthquakeFebruary 3, 1923 · 114 km NW of this epicenter
- 8.043 km E of Ust’-Kamchatsk Staryy, RussiaJanuary 30, 1917 · 273 km N of this epicenter
- 7.8off the east coast of the Kamchatka Peninsula, RussiaSeptember 15, 1905 · 254 km NE of this epicenter
- 7.7115 km ESE of Petropavlovsk-Kamchatsky, RussiaJune 25, 1904 · 157 km SW of this epicenter
- 7.5274 km SE of Petropavlovsk-Kamchatsky, RussiaJune 25, 1904 · 268 km S of this epicenter
- 7.3233 km SE of Atlasovo, RussiaJuly 31, 1915 · 30 km NE of this epicenter
- 7.377 km ESE of Mil’kovo, RussiaFebruary 3, 1923 · 153 km NW of this epicenter
- 7.3163 km ENE of Petropavlovsk-Kamchatsky, RussiaFebruary 2, 1923 · 67 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 17 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 21 recorded deaths. The most severe:
- 1923M7.2
Near Kamchatka
13 Apr 1923 · 300 km away · intensity X
18 deathsSevere damage ($5–24M)tsunami
- 1923M8.4
Kamchatka
3 Feb 1923 · 114 km away · intensity XI
3 deaths$2 million damagetsunami
- 1904M8.3
Off Kamchatka
25 Jun 1904 · 277 km away · intensity X
Limited damage (under $1M)tsunami
- 1904M8.1
Off Kamchatka
25 Jun 1904 · 277 km away · intensity X
Limited damage (under $1M)tsunami
- 1923M7.7
Kamchatka Peninsula
24 Feb 1923 · 136 km away
Limited damage (under $1M)
- 1827
Kamchatka
9 Aug 1827 · 238 km away
Limited damage (under $1M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.