Reviewed by USGSJapan31y ago
M4.6 earthquake 69 km SE of Nemuro, Japan
Thursday, April 20, 1995, 06:51:06 UTC · 42.906°N, 146.203°E
A magnitude 4.6 earthquake struck 69 km SE of Nemuro, Japan on Thursday, April 20, 1995, 06:51:06 UTC, at a depth of 33.0 km (shallow). It is the strongest earthquake within 300 km since an M5.8 on April 19, 1995.
- 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
72 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 1 M2.5+ earthquake within 50 km in the following 30 days; the largest was M4.7 on May 4, 1995. 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 1,239 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.31958 Kuril Islands EarthquakeNovember 6, 1958 · 253 km NE of this epicenter
- 8.348 km E of Shikotan, RussiaOctober 4, 1994 · 132 km NE of this epicenter
- 8.21969 Hokkaido Toho-oki EarthquakeAugust 11, 1969 · 143 km NE of this epicenter
- 8.11952 Tokachi-Oki EarthquakeMarch 4, 1952 · 210 km SW of this epicenter
- 7.7277 km SSE of Kushiro, JapanMay 3, 1919 · 255 km S of this epicenter
- 7.719 km ESE of Nemuro, JapanJune 17, 1973 · 50 km NW of this epicenter
- 7.6134 km SE of Kuril’sk, RussiaMarch 24, 1978 · 261 km NE of this epicenter
- 7.652 km NE of Otofuke, JapanJanuary 15, 1993 · 209 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 46 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 120 recorded deaths. The most severe:
- 1843M8.4
Hokkaido: Yezo, Kushiro, Nemuro
25 Apr 1843 · 102 km away
45 deathsModerate damage ($1–5M)tsunami
- 1952M8.1
Hokkaido
4 Mar 1952 · 210 km away · intensity IX
33 deathsSevere damage ($5–24M)tsunami
- 1973M7.7
Hokkaido Island
17 Jun 1973 · 46 km away · intensity VIII
27 deaths$5 million damagetsunami
- 1994M8.3
Kuril Islands; Japan: Hokkaido
4 Oct 1994 · 132 km away · intensity IX
11 deathsSevere damage ($5–24M)tsunami
- 1993M7.6
Hokkadio, Kushiro, Hachinohe, Honshu
15 Jan 1993 · 209 km away · intensity VI
2 deaths$358 million damage
- 1894M7.9
Off Coast Of Honshu
22 Mar 1894 · 48 km away · intensity IX
1 deathModerate damage ($1–5M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.