Reviewed by USGSBulgaria119y ago
M6.1 earthquake 11 km ENE of Elhovo, Bulgaria
Monday, February 15, 1909, 09:33:31 UTC · 42.221°N, 26.685°E
A magnitude 6.1 earthquake struck 11 km ENE of Elhovo, Bulgaria on Monday, February 15, 1909, 09:33:31 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M7.2 on November 8, 1905.
- Magnitude
- 6.1
- Strong · mw
- Depth
- 15 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
21 kilotons of TNT
That is about the energy of the Hiroshima bomb. It released about 43 times the energy of a magnitude 5.0.
Tectonic setting
165 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 has not published any M2.5+ earthquake within 100 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 5 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.2Aegean SeaNovember 8, 1905 · 293 km SW of this epicenter
- 7.07 km SE of Stara Kresna, BulgariaApril 4, 1904 · 289 km W of this epicenter
- 6.86 km W of Stara Kresna, BulgariaApril 4, 1904 · 299 km W of this epicenter
- 6.115 km NE of Bobov Dol, BulgariaOctober 8, 1905 · 292 km W of this epicenter
- 5.830 km SE of Marmara Ereğlisi, TurkeyOctober 22, 1905 · 205 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 27 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 13,371 recorded deaths. The most severe:
- 1719
Turkey
25 May 1719 · 276 km away · intensity X
6,000 deathsExtreme damage ($25M+)
- 1766M6.5
Turkey
22 May 1766 · 249 km away · intensity X
4,000 deathsExtreme damage ($25M+)tsunami
- 1754M6.8
Izmit
2 Sep 1754 · 262 km away · intensity IX
2,000 deathsExtreme damage ($25M+)tsunami
- 1894M6.7
Turkey
10 Jul 1894 · 246 km away · intensity X
1,349 deathsSevere damage ($5–24M)tsunami
- 1905M7.2
Aegean Sea
8 Nov 1905 · 293 km away · intensity X
11 deathsModerate damage ($1–5M)tsunami
- 1901M7.2
Balchik
31 Mar 1901 · 198 km away · intensity X
4 deathsSevere damage ($5–24M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.