M5.1 earthquake 44 km SW of Coquimbo, Chile

Saturday, March 12, 2016, 16:05:15 UTC · 30.250°S, 71.650°W

A magnitude 5.1 earthquake struck 44 km SW of Coquimbo, Chile on Saturday, March 12, 2016, 16:05:15 UTC, at a depth of 36.8 km (shallow). USGS received 3 “Did You Feel It?” reports, with a maximum reported intensity of IV (light). It is the strongest earthquake within 300 km since an M6.0 on February 22, 2016.

Magnitude: 5.1; Moderate · mww
Depth: 37 km; Shallow
Felt reports: 3; Max intensity IV
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

674 tons of TNT

That is about 1/22 of the Hiroshima bomb. It released about 1 times the energy of a magnitude 5.0.

Tectonic setting

91 km

from the nearest mapped plate boundary, between the Nazca and South American plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.

Depth: shallow

37 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
Coquimbo, Coquimbo, Chile	IV · Light	1	57 km
La Serena, Coquimbo, Chile	III · Weak	1	65 km
Ovalle, Coquimbo, Chile	III · Weak	1	68 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 18 M2.5+ earthquakes within 75 km in the following 30 days; the largest was M4.8 on March 25, 2016. 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 708 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 39 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 1,230 recorded deaths. The most severe:

1922M8.5
Atacama
11 Nov 1922 · 279 km away · intensity XI
700 deathsSevere damage ($5–24M)tsunami
1965M7.3
Central
28 Mar 1965 · 243 km away
400 deaths$125 million damage
1971M7.8
Central
9 Jul 1971 · 254 km away · intensity IX
83 deaths$236 million damagetsunami
2015M8.3
Central
16 Sep 2015 · 147 km away · intensity IX
15 deaths$600 million damagetsunami
1943M8.2
Illapel
6 Apr 1943 · 65 km away
11 deathsLimited damage (under $1M)tsunami
1997M7.1
Pueblo Nuevo, Coquimbo, La Chimba
15 Oct 1997 · 86 km away
8 deaths$48 million damage

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

Nearby trackers