Reviewed by USGSMexico84y ago
M7.4 earthquake 18 km SSW of Palos Blancos, Mexico
Monday, February 22, 1943, 09:20:48 UTC · 17.397°N, 101.370°W
A magnitude 7.4 earthquake struck 18 km SSW of Palos Blancos, Mexico on Monday, February 22, 1943, 09:20:48 UTC, at a depth of 20.0 km (shallow). It is the strongest earthquake within 300 km since an M7.6 on April 15, 1941.
- Magnitude
- 7.4
- Major · mw
- Depth
- 20 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- VII
- Very 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
1.9 megatons of TNT
That is about 126 times the Hiroshima bomb. It released about 3,981 times the energy of a magnitude 5.0.
Tectonic setting
52 km
from the nearest mapped plate boundary, between the Cocos and North American plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
20 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 200 km
USGS has not published any M2.5+ earthquake within 200 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 32 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.87 km E of Los Tepames, MexicoJune 18, 1932 · 297 km NW of this epicenter
- 7.621 km ESE of Coalcomán de Vázquez Pallares, MexicoApril 15, 1941 · 223 km NW of this epicenter
- 7.619 km W of Arteaga, MexicoJune 7, 1911 · 158 km NW of this epicenter
- 7.525 km S of Tetitlán, MexicoDecember 16, 1911 · 91 km SE of this epicenter
- 7.527 km SSE of San Andrés Playa Encantada (El Podrido), MexicoJuly 30, 1909 · 222 km SE of this epicenter
- 7.56 km S of Copala, MexicoMarch 26, 1908 · 271 km E of this epicenter
- 7.215 km SSW of Colonia Luces en el Mar, MexicoMarch 27, 1908 · 155 km SE of this epicenter
- 7.166 km SSW of Nuxco, MexicoOctober 31, 1909 · 94 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 36 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 322 recorded deaths. The most severe:
- 1912M6.7
Central, Acambay, Tixmadeje
19 Nov 1912 · 287 km away
202 deathsSevere damage ($5–24M)
- 1941M7.6
Michoacan, Colima, Jalisco
15 Apr 1941 · 223 km away · intensity VII
84 deaths$2 million damagetsunami
- 1864M7.0
Puebla,Veracruz,Acultzingo,Acatzingo
3 Oct 1864 · 135 km away
20 deathsSevere damage ($5–24M)
- 1907M8.3
Guerrero
15 Apr 1907 · 152 km away
8 deathsModerate damage ($1–5M)tsunami
- 1943M7.4
Guerrero: Paricutin Volcano Forms
22 Feb 1943 · 0 km away · intensity VII
5 deathsSevere damage ($5–24M)
- 1902M7.0
Guerrero
16 Jan 1902 · 177 km away
2 deathsModerate damage ($1–5M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.