Reviewed by USGSChile20y ago
M4.0 earthquake 63 km S of San Pedro de Atacama, Chile
Saturday, February 18, 2006, 23:42:46 UTC · 23.480°S, 68.171°W
A magnitude 4.0 earthquake struck 63 km S of San Pedro de Atacama, Chile on Saturday, February 18, 2006, 23:42:46 UTC, at a depth of 102.7 km (intermediate).
- Magnitude
- 4.0
- Light · mb
- Depth
- 103 km
- Intermediate
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquake
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
219 km
from the nearest mapped plate boundary, between the Altiplano and South American plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: intermediate
103 km
Intermediate-depth earthquakes usually break inside a plate that is sinking into the mantle. Shaking spreads over a wide area but is gentler at the epicenter than a shallow quake of the same size.
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 has not published any M2.5+ earthquake within 50 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 622 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.2121 km SSE of San Pedro de Atacama, ChileDecember 9, 1950 · 61 km SE of this epicenter
- 8.036 km NNE of Antofagasta, ChileJuly 30, 1995 · 217 km W of this epicenter
- 7.684 km SSE of Antofagasta, ChileMarch 5, 1987 · 226 km SW of this epicenter
- 7.583 km NNE of Taltal, ChileJuly 13, 1936 · 244 km SW of this epicenter
- 7.334 km NE of Tocopilla, ChileDecember 21, 1967 · 255 km NW of this epicenter
- 7.377 km NNE of Taltal, ChileDecember 2, 1960 · 257 km SW of this epicenter
- 7.275 km N of San Antonio de los Cobres, ArgentinaMay 12, 2000 · 175 km E of this epicenter
- 7.272 km N of Taltal, ChileFebruary 5, 1988 · 270 km SW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 20 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 11 recorded deaths. The most severe:
- 1953M7.4
Northern
7 Dec 1953 · 163 km away
3 deaths$7 million damage
- 1995M8.0
Antofagasta, Calama, Mejillones
30 Jul 1995 · 217 km away · intensity VII
3 deaths$2 million damagetsunami
- 1967M7.5
Northern
21 Dec 1967 · 240 km away
1 deathModerate damage ($1–5M)tsunami
- 1936M7.3
Taltal
13 Jul 1936 · 218 km away
1 deathModerate damage ($1–5M)tsunami
- 1987M7.3
Antofagasta, Arica
5 Mar 1987 · 226 km away · intensity VI
1 deathModerate damage ($1–5M)tsunami
- 1971M6.3
Catalina, Antofagasta
17 Jun 1971 · 248 km away · intensity V
1 deathModerate damage ($1–5M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.