Reviewed by USGSMexico118y ago
M6.9 earthquake 44 km SSE of San Andrés Playa Encantada (El Podrido), Mexico
Saturday, July 31, 1909, 19:18:52 UTC · 16.300°N, 99.523°W
A magnitude 6.9 earthquake struck 44 km SSE of San Andrés Playa Encantada (El Podrido), Mexico on Saturday, July 31, 1909, 19:18:52 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M7.5 on July 30, 1909.
- Magnitude
- 6.9
- Strong · 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 earthquake
In context
How big was it, and why here?
Energy released
315 kilotons of TNT
That is about 21 times the Hiroshima bomb. It released about 661 times the energy of a magnitude 5.0.
Tectonic setting
13 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
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 5 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 · 245 km E of this epicenter
- 7.527 km SSE of San Andrés Playa Encantada (El Podrido), MexicoJuly 30, 1909 · 18 km N of this epicenter
- 7.56 km S of Copala, MexicoMarch 26, 1908 · 63 km NE of this epicenter
- 7.215 km SSW of Colonia Luces en el Mar, MexicoMarch 27, 1908 · 79 km NW of this epicenter
- 6.711 km SSE of Hacienda de Cabañas, MexicoOctober 13, 1908 · 124 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 · 147 km away
20 deathsSevere damage ($5–24M)
- 1787M8.6
San Marcos, Oaxaca
28 Mar 1787 · 111 km away · intensity IX
11 deathsSevere damage ($5–24M)tsunami
- 1907M8.3
Guerrero
15 Apr 1907 · 93 km away
8 deathsModerate damage ($1–5M)tsunami
- 1882M7.5
Puebla,Huahuapan,Huamuxtitlan,Xalpatlahuac
19 Jul 1882 · 210 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 · 148 km away
2 deathsModerate damage ($1–5M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.