Reviewed by USGSGreece45y ago
M4.3 earthquake 6 km SW of Thívai, Greece
Thursday, July 2, 1981, 12:35:08 UTC · 38.281°N, 23.273°E
A magnitude 4.3 earthquake struck 6 km SW of Thívai, Greece on Thursday, July 2, 1981, 12:35:08 UTC, at a depth of 10.0 km (shallow).
- Magnitude
- 4.3
- Light · mb
- Depth
- 10 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
43 tons of TNT
That is about 1/354 of the Hiroshima bomb. A magnitude 5.0 releases about 11 times more energy.
Tectonic setting
41 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
10 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 M4.4 on July 26, 1981. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 3.49 km E of Erythrés, Greece45y ago · 15 km SE of this epicenter
- 4.412 km SSW of Kaparéllion, Greece45y ago · 20 km SW of this epicenter
- 3.96 km NE of Kaparéllion, Greece45y ago · 1 km SW of this epicenter
- 3.03 km SW of Perachóra, Greece45y ago · 44 km SW of this epicenter
- 4.29 km WSW of Kaparéllion, Greece45y ago · 17 km SW of this epicenter
- 4.03 km NNW of Erythrés, Greece45y ago · 5 km SE of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 415 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.9Southern GreeceAugust 11, 1903 · 255 km S of this epicenter
- 7.719 km SSE of Amorgós, GreeceJuly 9, 1956 · 297 km SE of this epicenter
- 7.34 km WNW of Koróni, GreeceOctober 6, 1947 · 203 km SW of this epicenter
- 7.2Aegean SeaNovember 8, 1905 · 233 km NE of this epicenter
- 7.29 km NNW of Karaburun, TurkeyJuly 23, 1949 · 283 km E of this epicenter
- 7.055 km S of Mýrina, GreeceFebruary 19, 1968 · 191 km NE of this epicenter
- 6.97 km NNE of Ágios Nikólaos, GreeceSeptember 26, 1932 · 229 km N of this epicenter
- 6.815 km ENE of Póros, GreeceAugust 12, 1953 · 204 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 144 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 28,877 recorded deaths. The most severe:
- 1883M7.3
Ayvalik, Izmir, Cesme
15 Oct 1883 · 255 km away · intensity X
15,000 deathsExtreme damage ($25M+)
- 1881M7.3
Khios; Turkey: Cesme
3 Apr 1881 · 260 km away · intensity XI
7,866 deathsExtreme damage ($25M+)tsunami
- 1750
Morea,Cerigo
7 Jun 1750 · 233 km away · intensity X
2,000 deaths
- 1867M7.0
Mitilini; Turkey: Izmir
7 Mar 1867 · 290 km away
563 deathsSevere damage ($5–24M)tsunami
- 1953M7.2
Lixouri-Argostoli (Kephallenia)
12 Aug 1953 · 216 km away · intensity X
476 deaths$100 million damagetsunami
- 1820M6.9
Zakinthos (Zante)
29 Dec 1820 · 187 km away · intensity X
388 deathsSevere damage ($5–24M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.