Reviewed by USGS54y ago
M5.4 earthquake in Kuril Islands
Sunday, March 25, 1973, 08:56:15 UTC · 50.237°N, 156.862°E
A magnitude 5.4 earthquake struck in Kuril Islands on Sunday, March 25, 1973, 08:56:15 UTC, at a depth of 40.0 km (shallow). It is the strongest earthquake within 300 km since an M6.1 on March 12, 1973.
- Magnitude
- 5.4
- Moderate · mb
- Depth
- 40 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
2 kilotons of TNT
That is about 1/8 of the Hiroshima bomb. It released about 4 times the energy of a magnitude 5.0.
Tectonic setting
117 km
from the nearest mapped plate boundary, between the Okhotsk and Pacific plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
40 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 2 M2.5+ earthquakes within 75 km in the following 30 days; the largest was M5.2 on April 12, 1973. 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 259 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.8266 km SSW of Severo-Kuril’sk, RussiaMay 1, 1915 · 246 km SW of this epicenter
- 7.5253 km SE of Vilyuchinsk, RussiaJune 30, 1936 · 298 km NE of this epicenter
- 7.495 km NNE of Ozernovskiy, RussiaMay 4, 1911 · 222 km N of this epicenter
- 7.4156 km SE of Severo-Kuril’sk, RussiaOctober 31, 1916 · 86 km SE of this epicenter
- 7.297 km NNE of Ozernovskiy, RussiaAugust 17, 1907 · 236 km N of this epicenter
- 7.238 km ESE of Severo-Kuril’sk, RussiaFebruary 28, 1973 · 34 km NW of this epicenter
- 7.0285 km S of Severo-Kuril’sk, RussiaAugust 1, 1913 · 244 km S of this epicenter
- 6.9251 km SSW of Severo-Kuril’sk, RussiaMay 22, 1963 · 240 km SW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 13 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 100 recorded deaths. The most severe:
- 1737
Kamchatka
16 Oct 1737 · 125 km away
100 deathstsunami
- 1841M8.4
Off Kamchatka
17 May 1841 · 212 km away · intensity XI
Moderate damage ($1–5M)tsunami
- 1973M7.2
Kuril Islands, Hiroo, Urakawa
28 Feb 1973 · 35 km away · intensity VIII
Moderate damage ($1–5M)tsunami
- 1904M8.3
Off Kamchatka
25 Jun 1904 · 246 km away · intensity X
Limited damage (under $1M)tsunami
- 1904M8.1
Off Kamchatka
25 Jun 1904 · 246 km away · intensity X
Limited damage (under $1M)tsunami
- 1904M7.9
Off Kamchatka
27 Jun 1904 · 246 km away · intensity IX
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.