Reviewed by USGSGreece99y ago
M5.5 earthquake 4 km N of Sofikón, Greece
Sunday, April 29, 1928, 09:49:17 UTC · 37.836°N, 23.059°E
A magnitude 5.5 earthquake struck 4 km N of Sofikón, Greece on Sunday, April 29, 1928, 09:49:17 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M6.3 on April 22, 1928.
- Magnitude
- 5.5
- 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 earthquake
In context
How big was it, and why here?
Energy released
3 kilotons of TNT
That is about 1/5 of the Hiroshima bomb. It released about 7 times the energy of a magnitude 5.0.
Tectonic setting
56 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 has not published any M2.5+ earthquake within 75 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 69 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.9Southern GreeceAugust 11, 1903 · 204 km S of this epicenter
- 7.2Aegean SeaNovember 8, 1905 · 285 km NE of this epicenter
- 6.56 km N of Tríkeri, GreeceJanuary 20, 1905 · 147 km N of this epicenter
- 6.532 km NNW of Lixoúri, GreeceAugust 7, 1915 · 247 km W of this epicenter
- 6.521 km SW of Lixoúri, GreeceJanuary 27, 1915 · 246 km W of this epicenter
- 6.411 km W of Kyllíni, GreeceJanuary 24, 1912 · 180 km W of this epicenter
- 6.418 km S of Pefkochóri, GreeceDecember 5, 1923 · 225 km N of this epicenter
- 6.334 km NW of Itháki, GreeceAugust 10, 1915 · 245 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 93 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 27,408 recorded deaths. The most severe:
- 1883M7.3
Ayvalik, Izmir, Cesme
15 Oct 1883 · 280 km away · intensity X
15,000 deathsExtreme damage ($25M+)
- 1881M7.3
Khios; Turkey: Cesme
3 Apr 1881 · 283 km away · intensity XI
7,866 deathsExtreme damage ($25M+)tsunami
- 1750
Morea,Cerigo
7 Jun 1750 · 182 km away · intensity X
2,000 deaths
- 1820M6.9
Zakinthos (Zante)
29 Dec 1820 · 159 km away · intensity X
388 deathsSevere damage ($5–24M)tsunami
- 1886M6.8
Triphylie (Peleponese), Philiatra
27 Aug 1886 · 145 km away · intensity X
326 deathsSevere damage ($5–24M)tsunami
- 1767M6.7
Kefalonia
11 Jul 1767 · 232 km away · intensity X
303 deathsSevere damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.