Reviewed by USGSChile19y ago
M3.9 earthquake 75 km SW of Tocopilla, Chile
Saturday, December 22, 2007, 12:33:37 UTC · 22.650°S, 70.626°W
A magnitude 3.9 earthquake struck 75 km SW of Tocopilla, Chile on Saturday, December 22, 2007, 12:33:37 UTC, at a depth of 7.0 km (shallow).
- Magnitude
- 3.9
- Minor · mb
- Depth
- 7 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
11 tons of TNT
That is about 1/1,410 of the Hiroshima bomb. A magnitude 5.0 releases about 45 times more energy.
Tectonic setting
74 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
7 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 3 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.0 on January 20, 2008. 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 552 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.036 km NNE of Antofagasta, ChileJuly 30, 1995 · 84 km SE of this epicenter
- 7.736 km ESE of Tocopilla, ChileNovember 14, 2007 · 88 km NE of this epicenter
- 7.684 km SSE of Antofagasta, ChileMarch 5, 1987 · 199 km S of this epicenter
- 7.583 km NNE of Taltal, ChileJuly 13, 1936 · 235 km S of this epicenter
- 7.334 km NE of Tocopilla, ChileDecember 21, 1967 · 110 km NE of this epicenter
- 7.377 km NNE of Taltal, ChileDecember 2, 1960 · 234 km S of this epicenter
- 7.334 km S of Iquique, ChileFebruary 23, 1933 · 241 km N of this epicenter
- 7.2Near the coast of Tarapaca, ChileOctober 4, 1940 · 298 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 2,397 recorded deaths. The most severe:
- 1877M8.3
Off North Coast
10 May 1877 · 129 km away · intensity XI
2,385 deaths$2 million damagetsunami
- 1953M7.4
Northern
7 Dec 1953 · 207 km away
3 deaths$7 million damage
- 1995M8.0
Antofagasta, Calama, Mejillones
30 Jul 1995 · 84 km away · intensity VII
3 deaths$2 million damagetsunami
- 2007M7.7
Tocopilla, Maria Elena
14 Nov 2007 · 88 km away · intensity VIII
2 deathsSevere damage ($5–24M)tsunami
- 1967M7.5
Northern
21 Dec 1967 · 157 km away
1 deathModerate damage ($1–5M)tsunami
- 1936M7.3
Taltal
13 Jul 1936 · 215 km away
1 deathModerate damage ($1–5M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.