Magnitude5.4

Reviewed by USGSGreece99y ago

M5.4 earthquake 4 km WNW of Mégara, Greece

Wednesday, April 25, 1928, 00:31:23 UTC · 38.012°N, 23.296°E

A magnitude 5.4 earthquake struck 4 km WNW of Mégara, Greece on Wednesday, April 25, 1928, 00:31:23 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
5.4
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

2 kilotons of TNT

That is about 1/8 of the Hiroshima bomb. It released about 4 times the energy of a magnitude 5.0.

Tectonic setting

57 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 M5.5 on April 29, 1928. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

M3M4M51h6h1d3d7d14d30dMainshock M5.4
Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.
  1. 5.54 km N of Sofikón, Greece99y ago · 29 km SW of this epicenter

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:

History · NOAA

Deadliest earthquakes in this area

NOAA’s significant-earthquake database lists 95 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 27,891 recorded deaths. The most severe:

  1. 1883M7.3

    Ayvalik, Izmir, Cesme

    15 Oct 1883 · 256 km away · intensity X

    15,000 deathsExtreme damage ($25M+)

  2. 1881M7.3

    Khios; Turkey: Cesme

    3 Apr 1881 · 260 km away · intensity XI

    7,866 deathsExtreme damage ($25M+)tsunami

  3. 1750

    Morea,Cerigo

    7 Jun 1750 · 203 km away · intensity X

    2,000 deaths

  4. 1867M7.0

    Mitilini; Turkey: Izmir

    7 Mar 1867 · 300 km away

    563 deathsSevere damage ($5–24M)tsunami

  5. 1820M6.9

    Zakinthos (Zante)

    29 Dec 1820 · 182 km away · intensity X

    388 deathsSevere damage ($5–24M)tsunami

  6. 1886M6.8

    Triphylie (Peleponese), Philiatra

    27 Aug 1886 · 173 km away · intensity X

    326 deathsSevere damage ($5–24M)tsunami

NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.

Nearby trackers

Closest city pages