Reviewed by USGSMexico118y ago
M7.5 earthquake 27 km SSE of San Andrés Playa Encantada (El Podrido), Mexico
Friday, July 30, 1909, 10:51:51 UTC · 16.463°N, 99.529°W
A magnitude 7.5 earthquake struck 27 km SSE of San Andrés Playa Encantada (El Podrido), Mexico on Friday, July 30, 1909, 10:51:51 UTC, at a depth of 20.0 km (shallow). It is the strongest earthquake within 300 km since an M7.8 on April 15, 1907.
- Magnitude
- 7.5
- 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 earthquakeDashed circle: 200 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
2.7 megatons of TNT
That is about 178 times the Hiroshima bomb. It released about 5,623 times the energy of a magnitude 5.0.
Tectonic setting
29 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 lists 1 M2.5+ earthquake within 200 km in the following 30 days; the largest was M6.9 on July 31, 1909. 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 4 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.82 km NW of Teojomulco, MexicoApril 15, 1907 · 244 km E of this epicenter
- 7.56 km S of Copala, MexicoMarch 26, 1908 · 59 km E of this epicenter
- 7.215 km SSW of Colonia Luces en el Mar, MexicoMarch 27, 1908 · 67 km NW of this epicenter
- 6.711 km SSE of Hacienda de Cabañas, MexicoOctober 13, 1908 · 112 km NW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 33 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 53 recorded deaths. The most severe:
- 1864M7.0
Puebla,Veracruz,Acultzingo,Acatzingo
3 Oct 1864 · 130 km away
20 deathsSevere damage ($5–24M)
- 1787M8.6
San Marcos, Oaxaca
28 Mar 1787 · 110 km away · intensity IX
11 deathsSevere damage ($5–24M)tsunami
- 1907M8.3
Guerrero
15 Apr 1907 · 78 km away
8 deathsModerate damage ($1–5M)tsunami
- 1882M7.5
Puebla,Huahuapan,Huamuxtitlan,Xalpatlahuac
19 Jul 1882 · 197 km away
7 deathsSevere damage ($5–24M)
- 1854M7.7
Veracruz,Oaxaca
5 May 1854 · 195 km away · intensity IX
4 deathsSevere damage ($5–24M)
- 1902M7.0
Guerrero
16 Jan 1902 · 130 km away
2 deathsModerate damage ($1–5M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.