Reviewed by USGSEcuador85y ago
M6.6 earthquake 29 km SE of Pedernales, Ecuador
Sunday, July 12, 1942, 05:05:20 UTC · 0.134°S, 79.878°W
A magnitude 6.6 earthquake struck 29 km SE of Pedernales, Ecuador on Sunday, July 12, 1942, 05:05:20 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M7.8 on May 14, 1942.
- Magnitude
- 6.6
- Strong · mw
- Depth
- 15 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 earthquake
In context
How big was it, and why here?
Energy released
104 kilotons of TNT
That is about 7 times the Hiroshima bomb. It released about 219 times the energy of a magnitude 5.0.
Tectonic setting
129 km
from the nearest mapped plate boundary, between the Nazca and North Andes plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
15 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 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 22 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.81906 Ecuador-Colombia EarthquakeJanuary 31, 1906 · 134 km NE of this epicenter
- 7.812 km SE of Pedernales, EcuadorMay 14, 1942 · 18 km NW of this epicenter
- 6.846 km SW of Paján, EcuadorOctober 2, 1933 · 211 km SW of this epicenter
- 6.813 km N of Muisne, EcuadorJune 30, 1916 · 98 km N of this epicenter
- 6.667 km NNW of Esmeraldas, EcuadorJune 1, 1907 · 181 km N of this epicenter
- 6.5197 km NW of Manta, EcuadorNovember 18, 1914 · 236 km W of this epicenter
- 6.427 km WSW of Muisne, EcuadorMay 17, 1942 · 85 km NW of this epicenter
- 6.323 km NW of Muisne, EcuadorJuly 8, 1942 · 104 km N of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 21 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 112,790 recorded deaths. The most severe:
- 1868M7.7
Guayaquil,Ibarra; Colombia: San Pablo
16 Aug 1868 · 195 km away · intensity X
70,000 deathsExtreme damage ($25M+)
- 1797M8.3
Riobamba, Quito, Cuzco; Peru; Colombia
4 Feb 1797 · 215 km away · intensity XI
40,000 deathsExtreme damage ($25M+)tsunami
- 1906M8.8
Off Coast
31 Jan 1906 · 134 km away · intensity IX
1,000 deathsSevere damage ($5–24M)tsunami
- 1757M7.0
Cotopaxi,Tungurahua, Latacunga
22 Feb 1757 · 166 km away · intensity IX
1,000 deathsSevere damage ($5–24M)
- 1923M6.2
Ipiales
14 Dec 1923 · 259 km away · intensity IX
300 deathsModerate damage ($1–5M)
- 1936M5.6
Colombia
9 Jan 1936 · 288 km away · intensity VII
250 deathsModerate damage ($1–5M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.