Reviewed by USGSPanama35y ago
M5.7 earthquake 2 km SW of La Mesa, Panama
Monday, May 27, 1991, 18:40:27 UTC · 9.482°N, 82.694°W
A magnitude 5.7 earthquake struck 2 km SW of La Mesa, Panama on Monday, May 27, 1991, 18:40:27 UTC, at a depth of 10.0 km (shallow). It is the strongest earthquake within 300 km since an M6.2 on May 4, 1991.
- Magnitude
- 5.7
- Moderate · mw
- Depth
- 10 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- VII
- Very strong (ShakeMap)
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 75 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
5 kilotons of TNT
That is about 1/3 of the Hiroshima bomb. It released about 11 times the energy of a magnitude 5.0.
Tectonic setting
21 km
from the nearest mapped plate boundary, between the Panama and Caribbean 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 75 km
USGS lists 1 M2.5+ earthquake within 75 km in the following 30 days; the largest was M4.6 on June 22, 1991. 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 223 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.634 km S of Limón, Costa RicaApril 22, 1991 · 47 km NW of this epicenter
- 7.64 km WNW of Atenas, Costa RicaDecember 21, 1939 · 197 km W of this epicenter
- 7.5Costa RicaOctober 5, 1950 · 281 km NW of this epicenter
- 7.544 km ESE of Burica, PanamaJuly 18, 1934 · 182 km S of this epicenter
- 7.570 km WSW of Golfito, Costa RicaDecember 5, 1941 · 169 km SW of this epicenter
- 7.37 km SSE of Puntarenas, Costa RicaMarch 25, 1990 · 237 km W of this epicenter
- 7.353 km SSE of Quepos, Costa RicaDecember 20, 1904 · 159 km W of this epicenter
- 7.245 km SW of Quebrada de Piedra, PanamaJanuary 20, 1904 · 202 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 35 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 871 recorded deaths. The most severe:
- 1910M6.4
Cartago, San Jose
4 May 1910 · 154 km away
700 deathsSevere damage ($5–24M)
- 1991M7.6
Limon, Pandora; Panama
22 Apr 1991 · 47 km away · intensity X
90 deaths$510 million damagetsunami
- 1952
Costa Rica
30 Dec 1952 · 127 km away
29 deaths
- 1973M6.5
Tilaran, Arenal, Rio Chiquito
14 Apr 1973 · 262 km away
26 deathsUnder $1 million damage
- 1955M5.8
Costa Rica
1 Sep 1955 · 206 km away
10 deathsModerate damage ($1–5M)
- 1941M7.6
Costa Rica-Panama
5 Dec 1941 · 103 km away · intensity IV
6 deathsModerate damage ($1–5M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.