Reviewed by USGSPeru106y ago
M6.8 earthquake 82 km SW of Islay (Matarani), Peru
Friday, January 6, 1922, 14:11:07 UTC · 17.536°S, 72.639°W
A magnitude 6.8 earthquake struck 82 km SW of Islay (Matarani), Peru on Friday, January 6, 1922, 14:11:07 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M7.2 on February 26, 1914.
- Magnitude
- 6.8
- Strong · mw
- Depth
- 15 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- V
- Moderate (ShakeMap)
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
208 kilotons of TNT
That is about 14 times the Hiroshima bomb. It released about 437 times the energy of a magnitude 5.0.
Tectonic setting
69 km
from the nearest mapped plate boundary, between the Nazca and Altiplano plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
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 6 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.737 km SSW of Atico, PeruAugust 6, 1913 · 161 km NW of this epicenter
- 7.212 km NNE of Cono Norte, PeruFebruary 26, 1914 · 187 km NE of this epicenter
- 6.925 km ENE of Arica, ChileAugust 30, 1906 · 285 km E of this epicenter
- 6.7165 km SSW of Atiquipa, PeruJuly 28, 1913 · 252 km W of this epicenter
- 6.7103 km SSW of Atico, PeruSeptember 13, 1919 · 157 km W of this epicenter
- 6.22 km S of Palca, PeruMay 5, 1906 · 285 km E of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 28 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 26,279 recorded deaths. The most severe:
- 1868M8.5
Arica
13 Aug 1868 · 210 km away · intensity XI
25,000 deaths$300 million damagetsunami
- 1833M7.7
Peru: Tacna; Chile: Arica
18 Sep 1833 · 190 km away · intensity VIII
700 deathsSevere damage ($5–24M)tsunami
- 1784M8.0
Arequipa,Camana,Moquegua,Tambo
13 May 1784 · 134 km away · intensity X
383 deathsSevere damage ($5–24M)tsunami
- 1821
Camana, Ocona, Caraveli
10 Jul 1821 · 163 km away · intensity VIII
162 deathsSevere damage ($5–24M)
- 1914
Pararca,Paysa,Colta,Oyala
2 Dec 1914 · 267 km away · intensity X
34 deathsSevere damage ($5–24M)
- 1913M7.9
Caraveli, Chuquibamba, Ocona, Atico
6 Aug 1913 · 156 km away · intensity X
Severe damage ($5–24M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.