Reviewed by USGSPeru57y ago
M5.5 earthquake 21 km NE of Palianñuñas, Peru
Wednesday, October 1, 1969, 22:56:27 UTC · 11.917°S, 75.038°W
A magnitude 5.5 earthquake struck 21 km NE of Palianñuñas, Peru on Wednesday, October 1, 1969, 22:56:27 UTC, at a depth of 10.0 km (shallow). It is the strongest earthquake within 300 km since an M6.0 on October 1, 1969.
- Magnitude
- 5.5
- Moderate · mw
- Depth
- 10 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
3 kilotons of TNT
That is about 1/5 of the Hiroshima bomb. It released about 6 times the energy of a magnitude 5.0.
Tectonic setting
189 km
from the nearest mapped plate boundary, between the Altiplano and South American plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
10 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 M5.4 on October 6, 1969. 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 32 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.221 km SE of Huacho, PeruMay 24, 1940 · 273 km W of this epicenter
- 7.623 km E of Santa Rosa, PeruNovember 1, 1947 · 113 km N of this epicenter
- 6.710 km SSW of Huacho, PeruMay 24, 1940 · 294 km W of this epicenter
- 6.616 km S of Comas, PeruOctober 1, 1969 · 8 km NW of this epicenter
- 6.512 km S of Chiara, PeruJanuary 9, 1921 · 187 km SE of this epicenter
- 6.518 km WSW of Oxapampa, PeruDecember 24, 1937 · 153 km N of this epicenter
- 6.329 km ESE of Santiago, PeruDecember 10, 1950 · 270 km S of this epicenter
- 6.33 km SE of Mariposa, PeruApril 28, 1958 · 64 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 31 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 6,550 recorded deaths. The most severe:
- 1746M8.0
Lima, Callao
29 Oct 1746 · 235 km away · intensity XI
5,941 deathsExtreme damage ($25M+)tsunami
- 1947M7.6
Satipo,Andamarca,Acobamba,La Merced,Victoc
1 Nov 1947 · 113 km away · intensity X
233 deathsSevere damage ($5–24M)
- 1940M8.2
Peru
24 May 1940 · 266 km away · intensity X
179 deathsSevere damage ($5–24M)tsunami
- 1969M6.6
Huaytapallana, Lampa, Chilifruta
1 Oct 1969 · 9 km away · intensity XI
130 deaths$5 million damage
- 1813
Ica
30 Mar 1813 · 246 km away · intensity VII
32 deathsModerate damage ($1–5M)
- 1937M6.5
Huancabamba,Oxapampa,El Progreso,San David
24 Dec 1937 · 219 km away · intensity X
15 deathsModerate damage ($1–5M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.