Reviewed by USGSMexico57y ago
M5.9 earthquake 87 km SSW of La Esperanza (El Zapotal), Mexico
Wednesday, April 29, 1970, 21:20:24 UTC · 14.702°N, 93.436°W
A magnitude 5.9 earthquake struck 87 km SSW of La Esperanza (El Zapotal), Mexico on Wednesday, April 29, 1970, 21:20:24 UTC, at a depth of 21.8 km (shallow). It is the strongest earthquake within 300 km since an M7.3 on April 29, 1970.
- Magnitude
- 5.9
- Moderate · mw
- Depth
- 22 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 earthquakeDashed circle: 75 km aftershock search area
In context
How big was it, and why here?
Energy released
10 kilotons of TNT
That is about 1/2 of the Hiroshima bomb. It released about 20 times the energy of a magnitude 5.0.
Tectonic setting
78 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
22 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 75 km
USGS lists 6 M2.5+ earthquakes within 75 km in the following 30 days; the largest was M6.6 on April 30, 1970. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 5.897 km SSW of La Esperanza (El Zapotal), Mexico57y ago · 23 km W of this epicenter
- 5.898 km SSW of La Esperanza (El Zapotal), Mexico57y ago · 19 km W of this epicenter
- 5.8101 km WSW of Puerto Madero, Mexico57y ago · 37 km SE of this epicenter
- 5.992 km SSW of La Esperanza (El Zapotal), Mexico57y ago · 11 km SE of this epicenter
- 6.0121 km WSW of Puerto Madero, Mexico57y ago · 48 km S of this epicenter
- 6.686 km WSW of Aquiles Serdán, Mexico57y ago · 27 km SE of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 115 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.726 km SSW of La Gomera, GuatemalaAugust 6, 1942 · 262 km E of this epicenter
- 7.34 km SSW of Puerto Madero, MexicoDecember 14, 1935 · 107 km E of this epicenter
- 7.334 km SW of Puerto Madero, MexicoApril 29, 1970 · 92 km E of this epicenter
- 7.2127 km SW of La Esperanza (El Zapotal), MexicoMarch 30, 1914 · 59 km W of this epicenter
- 7.21 km NNW of Champerico, GuatemalaOctober 23, 1950 · 169 km E of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 17 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 3,043 recorded deaths. The most severe:
- 1902M7.5
Quezaltenango, San Marcos
19 Apr 1902 · 274 km away
2,000 deathsSevere damage ($5–24M)tsunami
- 1773
St. Jago
3 Jun 1773 · 295 km away
600 deathsExtreme damage ($25M+)tsunami
- 1874M7.1
Antigua,Chimaltenango,Amatitlan
3 Sep 1874 · 295 km away · intensity VIII
300 deathsSevere damage ($5–24M)
- 1773M7.5
Antigua
29 Jul 1773 · 295 km away · intensity VIII
100 deathsModerate damage ($1–5M)
- 1816M7.5
Soloma
22 Jul 1816 · 226 km away · intensity IX
23 deathsSevere damage ($5–24M)
- 1968M6.1
S Chiapas
25 Sep 1968 · 137 km away
20 deathsModerate damage ($1–5M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.