Reviewed by USGSRussia53y ago
M4.6 earthquake 114 km SE of Shikotan, Russia
Friday, August 3, 1973, 19:13:05 UTC · 43.010°N, 147.635°E
A magnitude 4.6 earthquake struck 114 km SE of Shikotan, Russia on Friday, August 3, 1973, 19:13:05 UTC, at a depth of 53.0 km (shallow). It is the strongest earthquake within 300 km since an M5.0 on August 3, 1973.
- Magnitude
- 4.6
- Light · mb
- Depth
- 53 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
15 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
53 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 1 M2.5+ earthquake within 50 km in the following 30 days; the largest was M4.2 on August 3, 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 486 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 · 254 km NE of this epicenter
- 8.31958 Kuril Islands EarthquakeNovember 6, 1958 · 177 km N of this epicenter
- 8.21969 Hokkaido Toho-oki EarthquakeAugust 11, 1969 · 52 km N of this epicenter
- 7.719 km ESE of Nemuro, JapanJune 17, 1973 · 152 km W of this epicenter
- 7.542 km SSW of Shikotan, RussiaSeptember 11, 1935 · 94 km NW of this epicenter
- 7.4170 km ESE of Kuril’sk, RussiaFebruary 21, 1937 · 232 km NE of this epicenter
- 7.426 km S of Shikotan, RussiaJanuary 29, 1968 · 97 km NW of this epicenter
- 7.3Kuril IslandsApril 5, 1901 · 199 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 30 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 · 175 km away
45 deathsModerate damage ($1–5M)tsunami
- 1973M7.7
Hokkaido Island
17 Jun 1973 · 150 km away · intensity VIII
27 deaths$5 million damagetsunami
- 1894M7.9
Off Coast Of Honshu
22 Mar 1894 · 145 km away · intensity IX
1 deathModerate damage ($1–5M)tsunami
- 1938M6.1
E. Hokkaido Island, Japan
28 May 1938 · 278 km away
1 deathLimited damage (under $1M)tsunami
- 1958M8.3
Kuril Islands
6 Nov 1958 · 184 km away · intensity X
Moderate damage ($1–5M)tsunami
- 1969M8.2
Shikotan Island, Kurilskiye
11 Aug 1969 · 69 km away · intensity IX
Moderate damage ($1–5M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.