Reviewed by USGSGuatemala91y ago
M6.8 earthquake 20 km SE of Iztapa, Guatemala
Thursday, November 19, 1936, 21:10:24 UTC · 13.800°N, 90.572°W
A magnitude 6.8 earthquake struck 20 km SE of Iztapa, Guatemala on Thursday, November 19, 1936, 21:10:24 UTC, at a depth of 45.0 km (shallow). It is the strongest earthquake within 300 km since an M7.3 on December 14, 1935.
- Magnitude
- 6.8
- Strong · mw
- Depth
- 45 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
247 kilotons of TNT
That is about 16 times the Hiroshima bomb. It released about 519 times the energy of a magnitude 5.0.
Tectonic setting
5 km
from the nearest mapped plate boundary, between the Caribbean and North American plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
45 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 1 M2.5+ earthquake within 100 km in the following 30 days; the largest was M6.5 on November 22, 1936. 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 53 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 · 173 km E of this epicenter
- 7.34 km SSW of Puerto Madero, MexicoDecember 14, 1935 · 224 km NW of this epicenter
- 7.1113 km SSW of Puerto El Triunfo, El SalvadorFebruary 8, 1926 · 255 km SE of this epicenter
- 7.132 km NE of Chajul, GuatemalaFebruary 4, 1921 · 208 km N of this epicenter
- 7.0off the coast of Central AmericaJanuary 24, 1929 · 96 km S of this epicenter
- 7.031 km SE of Champerico, GuatemalaApril 17, 1919 · 128 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 37 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 8,415 recorded deaths. The most severe:
- 1917M6.0
Guatemala City
26 Dec 1917 · 89 km away · intensity IX
2,650 deathsExtreme damage ($25M+)
- 1902M7.5
Quezaltenango, San Marcos
19 Apr 1902 · 51 km away
2,000 deathsSevere damage ($5–24M)tsunami
- 1854
San Salvador
14 Apr 1854 · 148 km away
1,000 deathsExtreme damage ($25M+)
- 1873
Santa Tomas, San Vicente
4 Mar 1873 · 157 km away
800 deathsExtreme damage ($25M+)
- 1773
St. Jago
3 Jun 1773 · 90 km away
600 deathsExtreme damage ($25M+)tsunami
- 1936
San Vicente
19 Dec 1936 · 213 km away
400 deaths
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.