Reviewed by USGSGuatemala14y ago
M7.4 earthquake 33 km S of Champerico, Guatemala
Wednesday, November 7, 2012, 16:35:46 UTC · 13.988°N, 91.895°W
A magnitude 7.4 earthquake struck 33 km S of Champerico, Guatemala on Wednesday, November 7, 2012, 16:35:46 UTC, at a depth of 24.0 km (shallow). USGS received 728 “Did You Feel It?” reports, with a maximum reported intensity of VIII (severe). The USGS PAGER alert is yellow: some casualties and damage are possible. It is the strongest earthquake within 300 km since an M7.7 on August 6, 1942.
- Magnitude
- 7.4
- Major · mww
- Depth
- 24 km
- Shallow
- Felt reports
- 728
- Max intensity VIII
- Est. shaking
- VII
- Very strong (ShakeMap)
- PAGER alert
- Yellow
- Impact estimate
- 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
1.9 megatons of TNT
That is about 126 times the Hiroshima bomb. It released about 3,981 times the energy of a magnitude 5.0.
Tectonic setting
81 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
24 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
Reports sent by people to USGS, grouped by place (most reports first). Intensity uses the Modified Mercalli scale (I–X): what people felt, not the magnitude.
| Place | Intensity | Reports | Distance |
|---|---|---|---|
| Santa Catarina Pinula, Guatemala, Guatemala | V · Moderate | 114 | 165 km |
| Guatemala, Guatemala, Guatemala | V · Moderate | 108 | 163 km |
| Champerico, Retalhuleu, Guatemala | V · Moderate | 56 | 42 km |
| Mexico City, Distrito Federal, Mexico | III · Weak | 56 | 979 km |
| San Salvador, San Salvador, El Salvador | IV · Light | 47 | 295 km |
| Mixco, Guatemala, Guatemala | V · Moderate | 27 | 159 km |
| San Bartolomé Milpas Altas, Sacatepéquez, Guatemala | V · Moderate | 11 | 149 km |
| Nueva San Salvador, La Libertad, El Salvador | IV · Light | 10 | 284 km |
| Tuxtla Gutiérrez, Chiapas, Mexico | IV · Light | 9 | 333 km |
| San Cristóbal de las Casas, Chiapas, Mexico | IV · Light | 9 | 316 km |
| Antiguo Cuscatlán, La Libertad, El Salvador | IV · Light | 9 | 291 km |
| Belize, Belize, Belize | III · Weak | 9 | 556 km |
USGS PAGER estimate
Who was exposed to shaking
Modelled from the ShakeMap and population data. Alert level yellow: some casualties and damage are possible.
- VII · Very strong shaking
- 470,000 people
- VI · Strong shaking
- 3.1 million people
- V · Moderate shaking
- 6.7 million people
- IV · Light shaking
- 12 million people
- III · Weak shaking
- 37,000 people
Estimated shaking in nearby towns
- ChampericoPopulation 7,800VII · Very strong
- San Jose La MaquinaPopulation 0VII · Very strong
- RetalhuleucapitalPopulation 37,000VII · Very strong
- OcosPopulation 9,500VII · Very strong
- La BlancaPopulation 0VII · Very strong
- Flores Costa CucaPopulation 12,000VII · Very strong
- QuetzaltenangocapitalPopulation 132,000VI · Strong
- Guatemala CitycapitalPopulation 995,000V · Moderate
After the main event
Aftershocks within 200 km
USGS lists 123 M2.5+ earthquakes within 200 km in the following 30 days; the largest was M6.5 on November 11, 2012. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 4.39 km NE of San Juan Tecuaco, Guatemala14y ago · 184 km E of this epicenter
- 4.352 km SSW of Ocós, Guatemala14y ago · 57 km W of this epicenter
- 4.079 km SW of Champerico, Guatemala14y ago · 66 km W of this epicenter
- 4.2118 km SSW of La Esperanza (El Zapotal), Mexico14y ago · 195 km W of this epicenter
- 4.4Near the coast of Guatemala14y ago · 45 km SW of this epicenter
- 4.045 km SW of La Gomera, Guatemala14y ago · 69 km E of this epicenter
- 5.443 km SSW of Ocós, Guatemala14y ago · 55 km W of this epicenter
- 4.4near the coast of Guatemala14y ago · 172 km E of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 615 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 · 80 km E of this epicenter
- 7.34 km SSW of Puerto Madero, MexicoDecember 14, 1935 · 97 km NW of this epicenter
- 7.334 km SW of Puerto Madero, MexicoApril 29, 1970 · 94 km NW of this epicenter
- 7.318 km SSW of La Libertad, El SalvadorJune 19, 1982 · 281 km E of this epicenter
- 7.2127 km SW of La Esperanza (El Zapotal), MexicoMarch 30, 1914 · 235 km W of this epicenter
- 7.224 km W of Puerto Madero, MexicoSeptember 10, 1993 · 114 km NW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 48 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 8,301 recorded deaths. The most severe:
- 1917M6.0
Guatemala City
26 Dec 1917 · 155 km away · intensity IX
2,650 deathsExtreme damage ($25M+)
- 1902M7.5
Quezaltenango, San Marcos
19 Apr 1902 · 97 km away
2,000 deathsSevere damage ($5–24M)tsunami
- 1986M5.4
San Salvador
10 Oct 1986 · 300 km away
1,100 deaths$1.5 billion damage
- 1854
San Salvador
14 Apr 1854 · 292 km away
1,000 deathsExtreme damage ($25M+)
- 1773
St. Jago
3 Jun 1773 · 146 km away
600 deathsExtreme damage ($25M+)tsunami
- 1874M7.1
Antigua,Chimaltenango,Amatitlan
3 Sep 1874 · 141 km away · intensity VIII
300 deathsSevere damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.