Reviewed by USGSEl Salvador25y ago
M5.5 earthquake 39 km SW of Puerto El Triunfo, El Salvador
Tuesday, September 18, 2001, 14:51:03 UTC · 12.990°N, 88.761°W
A magnitude 5.5 earthquake struck 39 km SW of Puerto El Triunfo, El Salvador on Tuesday, September 18, 2001, 14:51:03 UTC, at a depth of 62.0 km (shallow). It is the strongest earthquake within 300 km since an M5.6 on August 12, 2001.
- Magnitude
- 5.5
- Moderate · mwc
- Depth
- 62 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- IV
- Light (ShakeMap)
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 75 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
3 kilotons of TNT
That is about 1/6 of the Hiroshima bomb. It released about 6 times the energy of a magnitude 5.0.
Tectonic setting
108 km
from the nearest mapped plate boundary, between the Caribbean and Cocos plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
62 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 3 M2.5+ earthquakes within 75 km in the following 30 days; the largest was M4.8 on September 28, 2001. 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 467 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.712 km NW of Chalatenango, El SalvadorSeptember 7, 1915 · 129 km N of this epicenter
- 7.783 km SSW of Corinto, NicaraguaSeptember 2, 1992 · 208 km SE of this epicenter
- 7.726 km SSW of La Gomera, GuatemalaAugust 6, 1942 · 277 km W of this epicenter
- 7.728 km SSW of Puerto El Triunfo, El SalvadorJanuary 13, 2001 · 13 km NE of this epicenter
- 7.57 km N of Los Amates, GuatemalaFebruary 4, 1976 · 262 km N of this epicenter
- 7.318 km SSW of La Libertad, El SalvadorJune 19, 1982 · 78 km NW of this epicenter
- 7.27 km SW of El Viejo, NicaraguaMarch 28, 1921 · 173 km E of this epicenter
- 7.2116 km SW of Corinto, NicaraguaJuly 1, 1907 · 178 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 67 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 46,107 recorded deaths. The most severe:
- 1976M7.5
Chimaltenango, Guatemala City
4 Feb 1976 · 262 km away · intensity IX
23,000 deaths$2.1 billion damagetsunami
- 1972M6.2
Managua
23 Dec 1972 · 296 km away
10,000 deaths$3.0 billion damage
- 1917M6.0
Guatemala City
26 Dec 1917 · 267 km away · intensity IX
2,650 deathsExtreme damage ($25M+)
- 1902M7.5
Quezaltenango, San Marcos
19 Apr 1902 · 267 km away
2,000 deathsSevere damage ($5–24M)tsunami
- 1986M5.4
San Salvador
10 Oct 1986 · 101 km away
1,100 deaths$1.5 billion damage
- 1951M6.5
Jucuapa
6 May 1951 · 104 km away
1,100 deaths$23 million damage
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.