Reviewed by USGSCosta Rica14y ago
M4.4 earthquake 16 km WNW of Sámara, Costa Rica
Sunday, October 21, 2012, 13:31:57 UTC · 9.951°N, 85.661°W
A magnitude 4.4 earthquake struck 16 km WNW of Sámara, Costa Rica on Sunday, October 21, 2012, 13:31:57 UTC, at a depth of 10.0 km (shallow). USGS received 3 “Did You Feel It?” reports, with a maximum reported intensity of IV (light).
- Magnitude
- 4.4
- Light · mb
- Depth
- 10 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: 50 km aftershock search area
In context
How big was it, and why here?
Energy released
60 tons of TNT
That is about 1/251 of the Hiroshima bomb. A magnitude 5.0 releases about 8 times more energy.
Tectonic setting
50 km
from the nearest mapped plate boundary, between the Sunda and Burma 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
3 people reported feeling this earthquake to USGS; a per-place breakdown is not available 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 4 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M6.5 on October 24, 2012. 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 418 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.783 km SSW of Corinto, NicaraguaSeptember 2, 1992 · 271 km NW of this epicenter
- 7.611 km ENE of Hojancha, Costa RicaSeptember 5, 2012 · 41 km E of this epicenter
- 7.634 km S of Limón, Costa RicaApril 22, 1991 · 285 km E of this epicenter
- 7.64 km WNW of Atenas, Costa RicaDecember 21, 1939 · 137 km E of this epicenter
- 7.5Costa RicaOctober 5, 1950 · 89 km NE of this epicenter
- 7.570 km WSW of Golfito, Costa RicaDecember 5, 1941 · 281 km SE of this epicenter
- 7.37 km SSE of Puntarenas, Costa RicaMarch 25, 1990 · 93 km E of this epicenter
- 7.392 km SW of San Juan del Sur, NicaraguaDecember 30, 1907 · 122 km NW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 49 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 12,071 recorded deaths. The most severe:
- 1972M6.2
Managua
23 Dec 1972 · 276 km away
10,000 deaths$3.0 billion damage
- 1930
Managua
31 Mar 1930 · 246 km away
1,000 deaths$15 million damage
- 1910M6.4
Cartago, San Jose
4 May 1910 · 182 km away
700 deathsSevere damage ($5–24M)
- 1992M7.6
Masachapa; Costa Rica
2 Sep 1992 · 274 km away
170 deaths$30 million damagetsunami
- 1991M7.6
Limon, Pandora; Panama
22 Apr 1991 · 285 km away · intensity X
90 deaths$510 million damagetsunami
- 1952
Costa Rica
30 Dec 1952 · 240 km away
29 deaths
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.