Reviewed by USGSChile10y ago
M4.5 earthquake 79 km W of Coquimbo, Chile
Monday, October 31, 2016, 21:04:52 UTC · 29.848°S, 72.152°W
A magnitude 4.5 earthquake struck 79 km W of Coquimbo, Chile on Monday, October 31, 2016, 21:04:52 UTC, at a depth of 7.7 km (shallow). It is the strongest earthquake within 300 km since an M4.9 on October 12, 2016.
- Magnitude
- 4.5
- Light · mwr
- Depth
- 8 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: 50 km aftershock search area
In context
How big was it, and why here?
Energy released
85 tons of TNT
That is about 1/178 of the Hiroshima bomb. A magnitude 5.0 releases about 6 times more energy.
Tectonic setting
41 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
8 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 50 km
USGS lists 2 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.4 on November 14, 2016. 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 625 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.594 km ENE of Vallenar, ChileNovember 11, 1922 · 283 km NE of this epicenter
- 8.348 km W of Illapel, ChileSeptember 16, 2015 · 197 km S of this epicenter
- 8.2The 1906 Valparaiso, Chile EarthquakeAugust 17, 1906 · 293 km S of this epicenter
- 8.145 km NNW of Illapel, ChileApril 6, 1943 · 174 km SE of this epicenter
- 7.136 km SW of Monte Patria, ChileOctober 15, 1997 · 150 km SE of this epicenter
- 7.086 km NW of La Serena, ChileMarch 19, 1904 · 76 km NE of this epicenter
- 7.025 km WNW of Illapel, ChileSeptember 16, 2015 · 203 km S of this epicenter
- 7.0118 km WNW of Vallenar, ChileNovember 7, 1922 · 166 km N of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 32 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 1,139 recorded deaths. The most severe:
- 1922M8.5
Atacama
11 Nov 1922 · 283 km away · intensity XI
700 deathsSevere damage ($5–24M)tsunami
- 1965M7.3
Central
28 Mar 1965 · 298 km away
400 deaths$125 million damage
- 2015M8.3
Central
16 Sep 2015 · 197 km away · intensity IX
15 deaths$600 million damagetsunami
- 1943M8.2
Illapel
6 Apr 1943 · 101 km away
11 deathsLimited damage (under $1M)tsunami
- 1997M7.1
Pueblo Nuevo, Coquimbo, La Chimba
15 Oct 1997 · 150 km away
8 deaths$48 million damage
- 1880M7.7
Illapel
15 Aug 1880 · 218 km away · intensity X
2 deathsSevere damage ($5–24M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.