Reviewed by USGSJapan34y ago
M4.5 earthquake 68 km ESE of Shizunai-furukawachō, Japan
Monday, February 1, 1993, 09:45:39 UTC · 42.072°N, 143.116°E
A magnitude 4.5 earthquake struck 68 km ESE of Shizunai-furukawachō, Japan on Monday, February 1, 1993, 09:45:39 UTC, at a depth of 66.0 km (shallow). It is the strongest earthquake within 300 km since an M4.8 on January 31, 1993.
- Magnitude
- 4.5
- Light · mb
- Depth
- 66 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
85 tons of TNT
That is about 1/178 of the Hiroshima bomb. A magnitude 5.0 releases about 6 times more energy.
Tectonic setting
174 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
66 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 2 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.8 on February 1, 1993. 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 852 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.21968 Tokachi-Oki EarthquakeMay 16, 1968 · 133 km S of this epicenter
- 8.11952 Tokachi-Oki EarthquakeMarch 4, 1952 · 65 km E of this epicenter
- 8.0113 km ENE of Miyako, JapanMarch 20, 1960 · 245 km S of this epicenter
- 7.978 km E of Hachinohe, JapanMarch 9, 1931 · 175 km S of this epicenter
- 7.970 km S of Honchō, JapanMay 16, 1968 · 67 km S of this epicenter
- 7.7277 km SSE of Kushiro, JapanMay 3, 1919 · 262 km SE of this epicenter
- 7.719 km ESE of Nemuro, JapanJune 17, 1973 · 254 km NE of this epicenter
- 7.652 km NE of Otofuke, JapanJanuary 15, 1993 · 144 km N of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 55 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 29,355 recorded deaths. The most severe:
- 1896M8.3
Sanriku
15 Jun 1896 · 296 km away
27,122 deathsExtreme damage ($25M+)tsunami
- 1766M6.9
Hirosaki
8 Mar 1766 · 240 km away
1,700 deathsSevere damage ($5–24M)tsunami
- 1896
Senhoku, Ugo
31 Aug 1896 · 291 km away
206 deathsExtreme damage ($25M+)
- 1982M6.7
Hokkaido, Urakawa, Hiroo
21 Mar 1982 · 63 km away · intensity X
110 deaths$1 million damagetsunami
- 1968M8.2
Off East Coast Of Honshu Island
16 May 1968 · 142 km away · intensity VI
52 deaths$131 million damagetsunami
- 1843M8.4
Hokkaido: Yezo, Kushiro, Nemuro
25 Apr 1843 · 238 km away
45 deathsModerate damage ($1–5M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.