Country profile · USGS ComCat
Earthquakes in Bulgaria
Bulgaria has catalogued 36 M4+ earthquakes since 2005 (ranked 112th of 187 countries), with the strongest reaching magnitude M7.1.
Bulgaria ranks 112th of 187 countries by catalogued seismic activity - a country with limited but non-zero seismic activity, averaging about 2 M4+ events a year alongside 7 significant M6+ earthquakes since 1900. The M6+ record here is thin - 7 events in all, so a single quake moves every figure on this page.
- 36
- M4+ events (since 2005)
- 7
- Major M6+ (since 1900)
- M7.1
- Strongest
- ~2
- M4+ per year
The verdict
Bulgaria is below the global median in catalogued seismic activity, with 36 M4+ earthquakes logged since 2005 and 7 major M6+ events since 1900, the strongest reaching magnitude 7.1.
- 1904
- busiest year (2 major events)
- 14 km
- average recorded event depth
- 100%
- of events are shallow (<70 km, the most damaging kind)
Average catalogued magnitude is 4.3 - most events are moderate M4-5 tremors that are felt but rarely cause damage. On the M4+ activity ladder Malaysia sits immediately above at 37 events and Bhutan sits immediately below at 35.
Catalog event strip
Event tape BULGARIA · Bulgaria M4+ · 112th/187
Bulgaria · 36 M4+ · max M7.1 · 7 M6+
- STRIP 36
- BOOK 112th/187
- RANK M7.1
- MAX 7
- M6 near Malaysia
- DEPTH 100% shallow
Stamps derive from this country's USGS ComCat row (M4+ book, rank, peak magnitude, M6+ record, ladder neighbour, depth/peak year), not a hazard forecast. PlainQuake is informational only - not professional advice and not a substitute for official USGS guidance. See our disclaimer. Verify with USGS ComCat → · Read with methodology → · How earthquakes are measured → · Reading earthquake data → · All country catalog rows → · Countries ranked →
Observed impact record
What ComCat observed after earthquakes in Bulgaria
USGS recorded Modified Mercalli Intensity (MMI) for 3 events in this catalogued record; their average observed intensity was MMI 7.4. These are only events with an observation, not an estimate of future shaking or a safety rating.
- MMI observations
- 3
- Average observed MMI
- 7.4
- PAGER alerts / tsunami flags
- 0 / 0
Source: USGS Comprehensive Earthquake Catalog (ComCat) GeoJSON impact fields. Missing MMI, alert, and tsunami values remain unreported rather than being treated as zero.
Where Bulgaria sits in the catalog
Rank 112th of 187 tracked countries (40th percentile by M4+ count since 2005). On the M4+ activity ladder Malaysia sits immediately above at 37 events and Bhutan sits immediately below at 35.
Same M4+ count, broken by peak magnitude
2 tracked countries share Bulgaria's exact count of 36 M4+ events since 2005. Among that cohort, Bulgaria ranks 2nd of 2 by strongest recorded magnitude (M5.0).
| Country | M4+ count | Strongest |
|---|---|---|
| Libya | 36 | M5.2 |
| Bulgaria (this page) | 36 | M5.0 |
Major (M6+) earthquakes in Bulgaria by year
Count of significant (magnitude 6.0+) events catalogued each year
- 1904
1904: 2 major (M6+) events
2
- 1905
1905: 1 major (M6+) events
1
- 1909
1909: 1 major (M6+) events
1
- 1913
1913: 1 major (M6+) events
1
- 1928
1928: 2 major (M6+) events
2
What this shows Bulgaria's most active year for major earthquakes was 1904 (2 M6+ events). Major-quake counts are irregular, they track the episodic release of tectonic stress, not a smooth trend.
0 of 36 catalogued M4+ events since 2005 reached M6.0 or higher.
Magnitude distribution of major events
Breakdown of the 7 significant (M6+) earthquakes on record for Bulgaria.
M7.0-7.9
3
42.9%
M6.0-6.9
4
57.1%
Depth of major earthquakes
Hypocentral depth of the 7 M6+ events, shallow quakes shake the surface hardest. Average depth: 14 km.
Shallow (<70 km)
7
100.0% of events
Intermediate (70–300 km)
0
0.0% of events
Deep (>300 km)
0
0.0% of events
Strongest earthquakes in Bulgaria
The 7 most powerful events on record (USGS, since 1900).
| Mag | Location | Depth | Date |
|---|---|---|---|
| 7.1 | 3 km W of Brezovo, Bulgaria | 10.0 km | Apr 18, 1928 |
| 7.1 | 9 km S of Stara Zagora, Bulgaria | 10.0 km | Apr 14, 1928 |
| 7.0 | 7 km SE of Stara Kresna, Bulgaria | 15.0 km | Apr 4, 1904 |
| 6.8 | 6 km W of Stara Kresna, Bulgaria | 15.0 km | Apr 4, 1904 |
| 6.7 | 5 km NNE of Lyaskovets, Bulgaria | 15.0 km | Jun 14, 1913 |
| 6.1 | 15 km NE of Bobov Dol, Bulgaria | 15.0 km | Oct 8, 1905 |
| 6.1 | 11 km ENE of Elhovo, Bulgaria | 15.0 km | Feb 15, 1909 |
Significant earthquake record (7 events)
Every catalogued magnitude-6.0-and-above earthquake in Bulgaria since 1900, most recent first.
| Mag | Location | Depth | Date |
|---|---|---|---|
| 7.1 | 3 km W of Brezovo, Bulgaria | 10.0 km | Apr 18, 1928 |
| 7.1 | 9 km S of Stara Zagora, Bulgaria | 10.0 km | Apr 14, 1928 |
| 6.7 | 5 km NNE of Lyaskovets, Bulgaria | 15.0 km | Jun 14, 1913 |
| 6.1 | 11 km ENE of Elhovo, Bulgaria | 15.0 km | Feb 15, 1909 |
| 6.1 | 15 km NE of Bobov Dol, Bulgaria | 15.0 km | Oct 8, 1905 |
| 7.0 | 7 km SE of Stara Kresna, Bulgaria | 15.0 km | Apr 4, 1904 |
| 6.8 | 6 km W of Stara Kresna, Bulgaria | 15.0 km | Apr 4, 1904 |
Other countries in this catalog sample
A Bulgaria-keyed shuffle of the full 186-country roster, not the six nearest by count.
Peak-magnitude sample from the same roster
A second Bulgaria-keyed shuffle of countries with a recorded max magnitude.
Showing 6 of 186 countries with a recorded max magnitude.
According to the US Geological Survey Earthquake Hazards Program, PlainQuake's figures are rendered directly from 317,293 recorded M4+ earthquakes and 14,444 significant M6+ events (USGS ComCat, 2005-present) -- no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2026-08-26.