Reviewed by USGSMexico97y ago
M6.4 earthquake 2 km NNW of San Marcial Ozolotepec, Mexico
Friday, January 16, 1931, 19:19:59 UTC · 16.107°N, 96.414°W
A magnitude 6.4 earthquake struck 2 km NNW of San Marcial Ozolotepec, Mexico on Friday, January 16, 1931, 19:19:59 UTC, at a depth of 30.0 km (shallow). It is the strongest earthquake within 300 km since an M7.6 on January 15, 1931.
- Magnitude
- 6.4
- Strong · mw
- Depth
- 30 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 earthquakeDashed circle: 100 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
54 kilotons of TNT
That is about 4 times the Hiroshima bomb. It released about 114 times the energy of a magnitude 5.0.
Tectonic setting
83 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
30 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 lists 2 M2.5+ earthquakes within 100 km in the following 30 days; the largest was M6.0 on January 17, 1931. 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 32 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 · 57 km W of this epicenter
- 7.82 km NW of Teojomulco, MexicoApril 15, 1907 · 105 km NW of this epicenter
- 7.65 km SSW of San Miguel Suchixtepec, MexicoJanuary 15, 1931 · 10 km SW of this epicenter
- 7.56 km WSW of San Miguel Panixtlahuaca, MexicoOctober 9, 1928 · 110 km W of this epicenter
- 7.56 km S of Copala, MexicoMarch 26, 1908 · 279 km W of this epicenter
- 7.48 km ENE of Santiago Xanica, MexicoMarch 22, 1928 · 29 km E of this epicenter
- 7.440 km S of Corralero, MexicoAugust 4, 1928 · 196 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 32 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 57 recorded deaths. The most severe:
- 1870M7.9
Oaxaca,Zanaguia,San Francisco Ozolotepec
11 May 1870 · 80 km away
24 deathsSevere damage ($5–24M)tsunami
- 1787M8.6
San Marcos, Oaxaca
28 Mar 1787 · 227 km away · intensity IX
11 deathsSevere damage ($5–24M)tsunami
- 1882M7.5
Puebla,Huahuapan,Huamuxtitlan,Xalpatlahuac
19 Jul 1882 · 260 km away
7 deathsSevere damage ($5–24M)
- 1801M7.0
Oaxaca
5 Oct 1801 · 35 km away
7 deathsSevere damage ($5–24M)
- 1854M7.7
Veracruz,Oaxaca
5 May 1854 · 140 km away · intensity IX
4 deathsSevere damage ($5–24M)
- 1928M7.7
Oaxaca
17 Jun 1928 · 67 km away
4 deathsModerate damage ($1–5M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.