Reviewed by USGSRussia54y ago
M4.6 earthquake 102 km SE of Severo-Kuril’sk, Russia
Friday, March 9, 1973, 13:58:41 UTC · 49.979°N, 157.069°E
A magnitude 4.6 earthquake struck 102 km SE of Severo-Kuril’sk, Russia on Friday, March 9, 1973, 13:58:41 UTC, at a depth of 33.0 km (shallow). It is the strongest earthquake within 300 km since an M5.0 on March 6, 1973.
- Magnitude
- 4.6
- Light · mb
- Depth
- 33 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: 50 km aftershock search area
In context
How big was it, and why here?
Energy released
120 tons of TNT
That is about 1/126 of the Hiroshima bomb. A magnitude 5.0 releases about 4 times more energy.
Tectonic setting
88 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
33 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 50 km
USGS lists 4 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M5.7 on March 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 255 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 · 232 km SW of this epicenter
- 7.5253 km SE of Vilyuchinsk, RussiaJune 30, 1936 · 297 km NE of this epicenter
- 7.495 km NNE of Ozernovskiy, RussiaMay 4, 1911 · 250 km N of this epicenter
- 7.4156 km SE of Severo-Kuril’sk, RussiaOctober 31, 1916 · 61 km E of this epicenter
- 7.297 km NNE of Ozernovskiy, RussiaAugust 17, 1907 · 265 km N of this epicenter
- 7.238 km ESE of Severo-Kuril’sk, RussiaFebruary 28, 1973 · 66 km NW of this epicenter
- 7.0285 km S of Severo-Kuril’sk, RussiaAugust 1, 1913 · 221 km S of this epicenter
- 6.9251 km SSW of Severo-Kuril’sk, RussiaMay 22, 1963 · 231 km SW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 14 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 · 141 km away
100 deathstsunami
- 1841M8.4
Off Kamchatka
17 May 1841 · 234 km away · intensity XI
Moderate damage ($1–5M)tsunami
- 1973M7.2
Kuril Islands, Hiroo, Urakawa
28 Feb 1973 · 67 km away · intensity VIII
Moderate damage ($1–5M)tsunami
- 1904M8.3
Off Kamchatka
25 Jun 1904 · 262 km away · intensity X
Limited damage (under $1M)tsunami
- 1904M8.1
Off Kamchatka
25 Jun 1904 · 262 km away · intensity X
Limited damage (under $1M)tsunami
- 1904M7.9
Off Kamchatka
27 Jun 1904 · 262 km away · intensity IX
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.