Reviewed by USGSCosta Rica123y ago
M7.3 earthquake 53 km SSE of Quepos, Costa Rica
Tuesday, December 20, 1904, 05:44:20 UTC · 8.962°N, 84.042°W
A magnitude 7.3 earthquake struck 53 km SSE of Quepos, Costa Rica on Tuesday, December 20, 1904, 05:44:20 UTC, at a depth of 10.0 km (shallow). No earthquake of this size or larger appears within 300 km in the USGS catalog since 1900.
- Magnitude
- 7.3
- Major · mw
- Depth
- 10 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 earthquake
In context
How big was it, and why here?
Energy released
1.3 megatons of TNT
That is about 86 times the Hiroshima bomb. It released about 2,723 times the energy of a magnitude 5.0.
Tectonic setting
53 km
from the nearest mapped plate boundary, between the Cocos and Panama 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
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 200 km
USGS has not published any M2.5+ earthquake within 200 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 2 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 13 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1854M7.3
Costa Rica-Panama
5 Aug 1854 · 126 km away
Severe damage ($5–24M)tsunami
- 1888
San Jose, Ala Juela, Heredia
30 Dec 1888 · 110 km away · intensity VIII
Severe damage ($5–24M)
- 1822M7.6
Matina
7 May 1822 · 129 km away · intensity VII
Moderate damage ($1–5M)tsunami
- 1844M7.4
Rivas, Greytown
May 1844 · 262 km away
Moderate damage ($1–5M)tsunami
- 1882M5.8
Alajuela, San Jose, Heredia
3 Mar 1882 · 31 km away · intensity VIII
Moderate damage ($1–5M)
- 1841
Cartago; Nicaragua
2 Sep 1841 · 116 km away
Moderate damage ($1–5M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.