Reviewed by USGSGreece59y ago
M5.3 earthquake 49 km NE of Skýros, Greece
Tuesday, February 20, 1968, 09:41:09 UTC · 39.272°N, 24.884°E
A magnitude 5.3 earthquake struck 49 km NE of Skýros, Greece on Tuesday, February 20, 1968, 09:41:09 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M5.6 on February 20, 1968.
- Magnitude
- 5.3
- Moderate · mw
- Depth
- 15 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: 75 km aftershock search area
In context
How big was it, and why here?
Energy released
1 kilotons of TNT
That is about 1/10 of the Hiroshima bomb. It released about 3 times the energy of a magnitude 5.0.
Tectonic setting
90 km
from the nearest mapped plate boundary, between the Aegean Sea and Eurasian plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
15 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 75 km
USGS lists 1 M2.5+ earthquake within 75 km in the following 30 days; the largest was M5.6 on March 10, 1968. 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 215 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.37 km N of Gönen, TurkeyMarch 18, 1953 · 257 km NE of this epicenter
- 7.2Aegean SeaNovember 8, 1905 · 94 km N of this epicenter
- 7.225 km SE of Malkara, TurkeyAugust 9, 1912 · 250 km NE of this epicenter
- 7.29 km NNW of Karaburun, TurkeyJuly 23, 1949 · 151 km SE of this epicenter
- 7.03 km ESE of Soma, TurkeyNovember 18, 1919 · 239 km E of this epicenter
- 7.055 km S of Mýrina, GreeceFebruary 19, 1968 · 14 km NE of this epicenter
- 6.97 km NNE of Ágios Nikólaos, GreeceSeptember 26, 1932 · 151 km NW of this epicenter
- 6.86 km SW of Galaxídhion, GreeceMarch 31, 1965 · 245 km SW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 90 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 28,685 recorded deaths. The most severe:
- 1883M7.3
Ayvalik, Izmir, Cesme
15 Oct 1883 · 157 km away · intensity X
15,000 deathsExtreme damage ($25M+)
- 1881M7.3
Khios; Turkey: Cesme
3 Apr 1881 · 164 km away · intensity XI
7,866 deathsExtreme damage ($25M+)tsunami
- 1912M7.2
Marmara Sea
9 Aug 1912 · 250 km away
2,800 deathsExtreme damage ($25M+)tsunami
- 1953M7.3
Yenice, Onon
18 Mar 1953 · 257 km away
1,070 deaths$4 million damage
- 1867M7.0
Mitilini; Turkey: Izmir
7 Mar 1867 · 131 km away
563 deathsSevere damage ($5–24M)tsunami
- 1894M6.7
Locride, Malesina-Martinon (Lokris)
20 Apr 1894 · 164 km away · intensity X
255 deathsSevere damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.