Magnitude6.4

Reviewed by USGSMexico103y ago

M6.4 earthquake 4 km NNW of San Lucas, Mexico

Monday, April 21, 1924, 20:00:59 UTC · 18.632°N, 100.802°W

A magnitude 6.4 earthquake struck 4 km NNW of San Lucas, Mexico on Monday, April 21, 1924, 20:00:59 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M6.5 on June 7, 1918.

Magnitude
6.4
Strong · mw
Depth
15 km
Shallow
Felt reports
0
Did You Feel It?
Est. shaking
VI
Strong (ShakeMap)
PAGER alert
None
Not issued
Tsunami
No flag
USGS feed

Outlined circle: this earthquakeColoured lines: estimated shaking intensity (USGS ShakeMap)

In context

How big was it, and why here?

Energy released

52 kilotons of TNT

That is about 3 times the Hiroshima bomb. It released about 110 times the energy of a magnitude 5.0.

Tectonic setting

201 km

from the nearest mapped plate boundary, between the Cocos and North American plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.

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 100 km

USGS has not published any M2.5+ earthquake within 100 km in the 30 days after this event.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 11 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 41 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 298 recorded deaths. The most severe:

  1. 1912M6.7

    Central, Acambay, Tixmadeje

    19 Nov 1912 · 141 km away

    202 deathsSevere damage ($5–24M)

  2. 1847

    Jalisco,Oaxaca,Michoacan

    2 Oct 1847 · 287 km away · intensity IX

    58 deathsSevere damage ($5–24M)

  3. 1864M7.0

    Puebla,Veracruz,Acultzingo,Acatzingo

    3 Oct 1864 · 146 km away

    20 deathsSevere damage ($5–24M)

  4. 1907M8.3

    Guerrero

    15 Apr 1907 · 200 km away

    8 deathsModerate damage ($1–5M)tsunami

  5. 1882M7.5

    Puebla,Huahuapan,Huamuxtitlan,Xalpatlahuac

    19 Jul 1882 · 294 km away

    7 deathsSevere damage ($5–24M)

  6. 1902M7.0

    Guerrero

    16 Jan 1902 · 161 km away

    2 deathsModerate damage ($1–5M)

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

Nearby trackers

Closest city pages