Reviewed by USGS93y ago
M6.8 earthquake south of Panama
Wednesday, July 18, 1934, 16:59:45 UTC · 7.458°N, 82.382°W
A magnitude 6.8 earthquake struck south of Panama on Wednesday, July 18, 1934, 16:59:45 UTC, at a depth of 25.0 km (shallow). It is the strongest earthquake within 300 km since an M7.5 on July 18, 1934.
- Magnitude
- 6.8
- Strong · mw
- Depth
- 25 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- V
- Moderate (ShakeMap)
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 100 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
265 kilotons of TNT
That is about 18 times the Hiroshima bomb. It released about 556 times the energy of a magnitude 5.0.
Tectonic setting
20 km
from the nearest mapped plate boundary, between the Nazca and Panama plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
25 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 100 km
USGS lists 1 M2.5+ earthquake within 100 km in the following 30 days; the largest was M6.8 on July 21, 1934. 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 32 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.544 km ESE of Burica, PanamaJuly 18, 1934 · 46 km N of this epicenter
- 7.353 km SSE of Quepos, Costa RicaDecember 20, 1904 · 248 km NW of this epicenter
- 7.245 km SW of Quebrada de Piedra, PanamaJanuary 20, 1904 · 59 km NE of this epicenter
- 6.8228 km WSW of Burica, PanamaMarch 3, 1906 · 254 km W of this epicenter
- 6.711 km NE of Changuinola, PanamaApril 26, 1916 · 228 km N of this epicenter
- 6.7260 km SSW of Arenas, PanamaAugust 20, 1927 · 246 km S of this epicenter
- 6.621 km ENE of Pedasí, PanamaOctober 2, 1913 · 281 km E of this epicenter
- 6.68 km SSW of Burica, PanamaJuly 18, 1934 · 79 km NW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 8 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 · 134 km away
Severe damage ($5–24M)tsunami
- 1822M7.6
Matina
7 May 1822 · 237 km away · intensity VII
Moderate damage ($1–5M)tsunami
- 1882M5.8
Alajuela, San Jose, Heredia
3 Mar 1882 · 278 km away · intensity VIII
Moderate damage ($1–5M)
- 1934M7.7
Panama-Costa Rica
18 Jul 1934 · 62 km away
Under $1 million damagetsunami
- 1916M7.0
Almirante, Bocas Del Toro
26 Apr 1916 · 242 km away · intensity IX
Under $1 million damagetsunami
- 1913M6.7
Azuero Peninsula
2 Oct 1913 · 201 km away
Limited damage (under $1M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.