Reviewed by USGSGreece22y ago
M2.9 earthquake 7 km SSW of Áyios Konstandínos, Greece
Monday, September 20, 2004, 05:41:19 UTC · 38.690°N, 22.830°E
A magnitude 2.9 earthquake struck 7 km SSW of Áyios Konstandínos, Greece on Monday, September 20, 2004, 05:41:19 UTC, at a depth of 8.0 km (shallow).
- Magnitude
- 2.9
- Minor · ml
- Depth
- 8 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
338 kg of TNT
That is about 1/44,601 of the Hiroshima bomb. A magnitude 5.0 releases about 1,413 times more energy.
Tectonic setting
14 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
8 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 6 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M3.2 on October 14, 2004. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 3.212 km WNW of Amfíkleia, Greece22y ago · 32 km W of this epicenter
- 2.76 km SE of Áyios Konstandínos, Greece22y ago · 7 km E of this epicenter
- 3.09 km ENE of Istiaía, Greece22y ago · 49 km NE of this epicenter
- 2.6Greece22y ago · 45 km NE of this epicenter
- 3.24 km SSW of Loutrá Aidhipsoú, Greece22y ago · 23 km NE of this epicenter
- 2.63 km NNE of Amfíkleia, Greece22y ago · 20 km W of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 547 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.9Southern GreeceAugust 11, 1903 · 299 km S of this epicenter
- 7.34 km WNW of Koróni, GreeceOctober 6, 1947 · 224 km S of this epicenter
- 7.2Aegean SeaNovember 8, 1905 · 219 km NE of this epicenter
- 7.261 km W of Eresós, GreeceDecember 19, 1981 · 216 km E of this epicenter
- 7.026 km SW of Lixoúri, GreeceJanuary 17, 1983 · 239 km W of this epicenter
- 7.055 km S of Mýrina, GreeceFebruary 19, 1968 · 200 km NE of this epicenter
- 6.97 km NNE of Ágios Nikólaos, GreeceSeptember 26, 1932 · 196 km NE of this epicenter
- 6.815 km ENE of Póros, GreeceAugust 12, 1953 · 174 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 175 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 21,005 recorded deaths. The most severe:
- 1883M7.3
Ayvalik, Izmir, Cesme
15 Oct 1883 · 296 km away · intensity X
15,000 deathsExtreme damage ($25M+)
- 1750
Morea,Cerigo
7 Jun 1750 · 277 km away · intensity X
2,000 deaths
- 1953M7.2
Lixouri-Argostoli (Kephallenia)
12 Aug 1953 · 182 km away · intensity X
476 deaths$100 million damagetsunami
- 1820M6.9
Zakinthos (Zante)
29 Dec 1820 · 173 km away · intensity X
388 deathsSevere damage ($5–24M)tsunami
- 1886M6.8
Triphylie (Peleponese), Philiatra
27 Aug 1886 · 203 km away · intensity X
326 deathsSevere damage ($5–24M)tsunami
- 1767M6.7
Kefalonia
11 Jul 1767 · 211 km away · intensity X
303 deathsSevere damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.