Reviewed by USGSRussia53y ago
M4.2 earthquake 145 km SSE of Shikotan, Russia
Friday, August 3, 1973, 22:27:33 UTC · 42.713°N, 147.720°E
A magnitude 4.2 earthquake struck 145 km SSE of Shikotan, Russia on Friday, August 3, 1973, 22:27:33 UTC, at a depth of 56.0 km (shallow).
- Magnitude
- 4.2
- Light · mb
- Depth
- 56 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 earthquake
In context
How big was it, and why here?
Energy released
30 tons of TNT
That is about 1/500 of the Hiroshima bomb. A magnitude 5.0 releases about 16 times more energy.
Tectonic setting
16 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
56 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 has not published any M2.5+ earthquake within 50 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 460 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.51963 Kuril Islands EarthquakeOctober 13, 1963 · 279 km NE of this epicenter
- 8.31958 Kuril Islands EarthquakeNovember 6, 1958 · 206 km N of this epicenter
- 8.21969 Hokkaido Toho-oki EarthquakeAugust 11, 1969 · 84 km N of this epicenter
- 7.7277 km SSE of Kushiro, JapanMay 3, 1919 · 287 km SW of this epicenter
- 7.719 km ESE of Nemuro, JapanJune 17, 1973 · 168 km W of this epicenter
- 7.542 km SSW of Shikotan, RussiaSeptember 11, 1935 · 119 km NW of this epicenter
- 7.4170 km ESE of Kuril’sk, RussiaFebruary 21, 1937 · 252 km NE of this epicenter
- 7.426 km S of Shikotan, RussiaJanuary 29, 1968 · 125 km NW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 29 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 74 recorded deaths. The most severe:
- 1843M8.4
Hokkaido: Yezo, Kushiro, Nemuro
25 Apr 1843 · 162 km away
45 deathsModerate damage ($1–5M)tsunami
- 1973M7.7
Hokkaido Island
17 Jun 1973 · 165 km away · intensity VIII
27 deaths$5 million damagetsunami
- 1894M7.9
Off Coast Of Honshu
22 Mar 1894 · 143 km away · intensity IX
1 deathModerate damage ($1–5M)tsunami
- 1938M6.1
E. Hokkaido Island, Japan
28 May 1938 · 294 km away
1 deathLimited damage (under $1M)tsunami
- 1958M8.3
Kuril Islands
6 Nov 1958 · 213 km away · intensity X
Moderate damage ($1–5M)tsunami
- 1969M8.2
Shikotan Island, Kurilskiye
11 Aug 1969 · 100 km away · intensity IX
Moderate damage ($1–5M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.