Reviewed by USGSChile10y ago
M4.0 earthquake 83 km WNW of Coquimbo, Chile
Friday, August 26, 2016, 21:00:48 UTC · 29.602°S, 72.104°W
A magnitude 4.0 earthquake struck 83 km WNW of Coquimbo, Chile on Friday, August 26, 2016, 21:00:48 UTC, at a depth of 10.0 km (shallow). USGS received 1 “Did You Feel It?” report, with a maximum reported intensity of III (weak).
- Magnitude
- 4.0
- Light · mwr
- Depth
- 10 km
- Shallow
- Felt reports
- 1
- Max intensity III
- 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
15 tons of TNT
That is about 1/998 of the Hiroshima bomb. A magnitude 5.0 releases about 32 times more energy.
Tectonic setting
44 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
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
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 |
|---|---|---|---|
| Valparaíso, Valparaíso, Chile | III · Weak | 1 | 383 km |
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 1 M2.5+ earthquake within 50 km in the following 30 days; the largest was M3.7 on September 24, 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 634 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 · 263 km NE of this epicenter
- 8.348 km W of Illapel, ChileSeptember 16, 2015 · 223 km S of this epicenter
- 8.145 km NNW of Illapel, ChileApril 6, 1943 · 198 km S of this epicenter
- 7.4Atacama, ChileApril 18, 1939 · 291 km NE of this epicenter
- 7.136 km SW of Monte Patria, ChileOctober 15, 1997 · 171 km SE of this epicenter
- 7.086 km NW of La Serena, ChileMarch 19, 1904 · 51 km NE of this epicenter
- 7.025 km WNW of Illapel, ChileSeptember 16, 2015 · 227 km S of this epicenter
- 7.0118 km WNW of Vallenar, ChileNovember 7, 1922 · 138 km N of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 30 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 739 recorded deaths. The most severe:
- 1922M8.5
Atacama
11 Nov 1922 · 263 km away · intensity XI
700 deathsSevere damage ($5–24M)tsunami
- 2015M8.3
Central
16 Sep 2015 · 223 km away · intensity IX
15 deaths$600 million damagetsunami
- 1943M8.2
Illapel
6 Apr 1943 · 128 km away
11 deathsLimited damage (under $1M)tsunami
- 1997M7.1
Pueblo Nuevo, Coquimbo, La Chimba
15 Oct 1997 · 171 km away
8 deaths$48 million damage
- 1880M7.7
Illapel
15 Aug 1880 · 241 km away · intensity X
2 deathsSevere damage ($5–24M)tsunami
- 1975M6.9
Coquimbo, La Serena
13 Mar 1975 · 84 km away · intensity VIII
2 deathsLimited damage (under $1M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.