Reviewed by USGSMexico70y ago
M7.6 earthquake 8 km ENE of Apantla, Mexico
Sunday, July 28, 1957, 08:40:12 UTC · 17.055°N, 99.092°W
A magnitude 7.6 earthquake struck 8 km ENE of Apantla, Mexico on Sunday, July 28, 1957, 08:40:12 UTC, at a depth of 37.8 km (shallow). It is the strongest earthquake within 300 km since an M7.6 on January 15, 1931.
- Magnitude
- 7.6
- Major · mw
- Depth
- 38 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 earthquakeDashed circle: 200 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
3.8 megatons of TNT
That is about 252 times the Hiroshima bomb. It released about 7,943 times the energy of a magnitude 5.0.
Tectonic setting
108 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
38 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 lists 3 M2.5+ earthquakes within 200 km in the following 30 days; the largest was M6.0 on August 18, 1957. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 68 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.015 km ESE of San Gabriel Mixtepec, MexicoJune 17, 1928 · 254 km SE of this epicenter
- 7.82 km NW of Teojomulco, MexicoApril 15, 1907 · 203 km E of this epicenter
- 7.65 km SSW of San Miguel Suchixtepec, MexicoJanuary 15, 1931 · 299 km E of this epicenter
- 7.56 km WSW of San Miguel Panixtlahuaca, MexicoOctober 9, 1928 · 199 km SE of this epicenter
- 7.525 km S of Tetitlán, MexicoDecember 16, 1911 · 168 km W of this epicenter
- 7.527 km SSE of San Andrés Playa Encantada (El Podrido), MexicoJuly 30, 1909 · 81 km SW of this epicenter
- 7.56 km S of Copala, MexicoMarch 26, 1908 · 58 km S of this epicenter
- 7.43 km W of Huixtepec, MexicoDecember 23, 1937 · 92 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 70 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 334 recorded deaths. The most severe:
- 1912M6.7
Central, Acambay, Tixmadeje
19 Nov 1912 · 291 km away
202 deathsSevere damage ($5–24M)
- 1957M7.9
Acapulco,Mexico City
28 Jul 1957 · 62 km away · intensity VII
65 deaths$25 million damagetsunami
- 1864M7.0
Puebla,Veracruz,Acultzingo,Acatzingo
3 Oct 1864 · 118 km away
20 deathsSevere damage ($5–24M)
- 1787M8.6
San Marcos, Oaxaca
28 Mar 1787 · 88 km away · intensity IX
11 deathsSevere damage ($5–24M)tsunami
- 1907M8.3
Guerrero
15 Apr 1907 · 97 km away
8 deathsModerate damage ($1–5M)tsunami
- 1882M7.5
Puebla,Huahuapan,Huamuxtitlan,Xalpatlahuac
19 Jul 1882 · 119 km away
7 deathsSevere damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.