M5.5 earthquake 7 km NNE of Cañete, Chile

Saturday, October 23, 2010, 05:58:27 UTC · 37.743°S, 73.362°W

A magnitude 5.5 earthquake struck 7 km NNE of Cañete, Chile on Saturday, October 23, 2010, 05:58:27 UTC, at a depth of 15.0 km (shallow). USGS received 26 “Did You Feel It?” reports, with a maximum reported intensity of VI (strong). It is the strongest earthquake within 300 km since an M5.8 on September 30, 2010.

Magnitude: 5.5; Moderate · mwb
Depth: 15 km; Shallow
Felt reports: 26; Max intensity VI
Est. shaking: VI; Strong (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

110 km

from the nearest mapped plate boundary, between the Nazca and South American 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

Reports sent by people to USGS, grouped by place (most reports first). Intensity uses the Modified Mercalli scale (I–X): what people felt, not the magnitude.

Place	Intensity	Reports	Distance
Temuco, Araucanía, Chile	III · Weak	5	130 km
Curanilahue, Bío Bío, Chile	V · Moderate	3	32 km
Concepción, Bío Bío, Chile	IV · Light	3	106 km
Chillán, Bío Bío, Chile	III · Weak	3	169 km
Valdivia, Los Lagos, Chile	II · Weak	3	231 km
Los Angeles, Bío Bío, Chile	V · Moderate	2	95 km
Villarrica, Araucanía, Chile	II · Weak	2	197 km
Talcahuano, Bío Bío, Chile	VI · Strong	1	114 km
Angol, Araucanía, Chile	VI · Strong	1	59 km
Traiguén, Araucanía, Chile	V · Moderate	1	83 km
Cañete, Bío Bío, Chile	IV · Light	1	17 km
Laja, Bío Bío, Chile	IV · Light	1	78 km

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 5 M2.5+ earthquakes within 75 km in the following 30 days; the largest was M5.2 on November 20, 2010. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 385 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:

History · NOAA

Deadliest earthquakes in this area

NOAA’s significant-earthquake database lists 23 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 32,974 recorded deaths. The most severe:

1939M8.3
Chillan
25 Jan 1939 · 193 km away · intensity X
30,000 deaths$920 million damagetsunami
1960M9.5
Puerto Montt, Valdivia
22 May 1960 · 45 km away · intensity XII
2,226 deaths$1.0 billion damagetsunami
2010M8.8
Maule, Concepcion, Talcahuano
27 Feb 2010 · 185 km away · intensity IX
558 deaths$30 billion damagetsunami
1751M8.5
Concepcion, Chillan, Talca, Tutuben, Curico
25 May 1751 · 184 km away · intensity XI
65 deathsSevere damage ($5–24M)tsunami
1949M7.3
Angol, Traiguen
20 Apr 1949 · 31 km away
57 deathsModerate damage ($1–5M)tsunami
1835M8.2
Concepcion
20 Feb 1835 · 106 km away · intensity XI
53 deathsExtreme damage ($25M+)tsunami

NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.

Nearby trackers