Reviewed by USGSGeorgia122y ago
M6.4 earthquake 28 km N of Tqvarch'eli, Georgia
Saturday, October 21, 1905, 11:01:27 UTC · 43.096°N, 41.664°E
A magnitude 6.4 earthquake struck 28 km N of Tqvarch'eli, Georgia on Saturday, October 21, 1905, 11:01:27 UTC, at a depth of 15.0 km (shallow). No earthquake of this size or larger appears within 300 km in the USGS catalog since 1900.
- Magnitude
- 6.4
- Strong · mw
- Depth
- 15 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: 100 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
54 kilotons of TNT
That is about 4 times the Hiroshima bomb. It released about 114 times the energy of a magnitude 5.0.
Tectonic setting
401 km
from the nearest mapped plate boundary, between the Anatolian and Eurasian plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
15 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 M5.6 on October 21, 1905. 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 no earlier M5.0+ earthquakes within 300 km.
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 5 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 1,247 recorded deaths. The most severe:
- 1903M5.8
Varginis,Cardahli,Mehkerek
28 May 1903 · 259 km away · intensity VIII
1,000 deathsSevere damage ($5–24M)
- 1899M5.6
Turkey
31 Dec 1899 · 225 km away
247 deathsModerate damage ($1–5M)
- 1888M6.1
Turkey
22 Sep 1888 · 241 km away
Moderate damage ($1–5M)
- 1868M4.5
Spask
18 Oct 1868 · 275 km away · intensity VII
Moderate damage ($1–5M)
- 1905M7.5
Caucasus
21 Oct 1905 · 125 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.