Reviewed by USGSMexico99y ago
M6.5 earthquake 10 km NE of San Antonio las Palmas, Mexico
Tuesday, April 17, 1928, 03:25:27 UTC · 17.731°N, 96.019°W
A magnitude 6.5 earthquake struck 10 km NE of San Antonio las Palmas, Mexico on Tuesday, April 17, 1928, 03:25:27 UTC, at a depth of 80.0 km (intermediate). It is the strongest earthquake within 300 km since an M7.4 on March 22, 1928.
- Magnitude
- 6.5
- Strong · mw
- Depth
- 80 km
- Intermediate
- 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
94 kilotons of TNT
That is about 6 times the Hiroshima bomb. It released about 197 times the energy of a magnitude 5.0.
Tectonic setting
263 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: intermediate
80 km
Intermediate-depth earthquakes usually break inside a plate that is sinking into the mantle. Shaking spreads over a wide area but is gentler at the epicenter than a shallow quake of the same size.
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 10 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 · 181 km SW of this epicenter
- 7.48 km ENE of Santiago Xanica, MexicoMarch 22, 1928 · 189 km S of this epicenter
- 7.231 km S of San Francisco Cozoaltepec, MexicoDecember 29, 1917 · 257 km S of this epicenter
- 7.07 km N of Jesús Carranza, MexicoJune 2, 1916 · 109 km E of this epicenter
- 6.54 km ESE of Santa María Jicaltepec, MexicoSeptember 24, 1910 · 261 km SW of this epicenter
- 6.47 km W of San Felipe Tejalápam, MexicoApril 19, 1920 · 119 km SW of this epicenter
- 6.329 km SSE of El Carrizal, MexicoJune 14, 1913 · 227 km S of this epicenter
- 6.35 km NE of Ejido la Piña (Maromilla), MexicoJanuary 4, 1920 · 166 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 705 recorded deaths. The most severe:
- 1920M7.8
Veracruz: Cozautlan, Puebla: Patlanala
3 Jan 1920 · 197 km away · intensity X
648 deathsModerate damage ($1–5M)
- 1870M7.9
Oaxaca,Zanaguia,San Francisco Ozolotepec
11 May 1870 · 261 km away
24 deathsSevere damage ($5–24M)tsunami
- 1787M8.6
San Marcos, Oaxaca
28 Mar 1787 · 297 km away · intensity IX
11 deathsSevere damage ($5–24M)tsunami
- 1882M7.5
Puebla,Huahuapan,Huamuxtitlan,Xalpatlahuac
19 Jul 1882 · 231 km away
7 deathsSevere damage ($5–24M)
- 1801M7.0
Oaxaca
5 Oct 1801 · 170 km away
7 deathsSevere damage ($5–24M)
- 1854M7.7
Veracruz,Oaxaca
5 May 1854 · 236 km away · intensity IX
4 deathsSevere damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.