Country profile · USGS ComCat
Earthquakes in Saint Helena
Saint Helena has catalogued 185 M4+ earthquakes since 2005 (ranked 64th of 187 countries), with the strongest reaching magnitude M6.1.
Saint Helena ranks 64th of 187 countries by catalogued seismic activity - a country with limited but non-zero seismic activity, averaging about 9 M4+ events a year alongside 4 significant M6+ earthquakes since 1900. The M6+ record here is thin - 4 events in all, so a single quake moves every figure on this page.
- 185
- M4+ events (since 2005)
- 4
- Major M6+ (since 1900)
- M6.1
- Strongest
- ~9
- M4+ per year
The verdict
Saint Helena is moderately seismically active, above the global median, with 185 M4+ earthquakes logged since 2005 and 4 major M6+ events since 1900, the strongest reaching magnitude 6.1.
- 1922
- busiest year (1 major events)
- 11 km
- average recorded event depth
- 100%
- of events are shallow (<70 km, the most damaging kind)
Average catalogued magnitude is 4.8 - most events are moderate M4-5 tremors that are felt but rarely cause damage. On the M4+ activity ladder Romania sits immediately above at 186 events and Kazakhstan sits immediately below at 173.
Catalog event strip
Event tape SAINT-HELENA · Saint Helena M4+ · 64th/187
Saint Helena · 185 M4+ · max M6.1 · 4 M6+
- RANK 185
- MAX 64th/187
- M6 M6.1
- DEPTH 4
- PHOTO near Romania
- BUSY 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 →
Where Saint Helena sits in the catalog
Rank 64th of 187 tracked countries (66th percentile by M4+ count since 2005). On the M4+ activity ladder Romania sits immediately above at 186 events and Kazakhstan sits immediately below at 173.
- Romania - next more active (186 M4+)
- Kazakhstan - next less active (173 M4+)
Saint Helena's M4+ count vs. every tracked country
Total catalogued M4+ events since 2005, USGS ComCat
185 Top 34% higher than 66% of 187 countries
Each bar is a 500-wide band; taller bars hold more countries. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source USGS Comprehensive Earthquake Catalog (ComCat) · 2005-present
Major (M6+) earthquakes in Saint Helena by year
Count of significant (magnitude 6.0+) events catalogued each year
- 1922
1922: 1 major (M6+) events
1
- 1947
1947: 1 major (M6+) events
1
- 2001
2001: 1 major (M6+) events
1
- 2011
2011: 1 major (M6+) events
1
What this shows Saint Helena's most active year for major earthquakes was 1922 (1 M6+ events). Major-quake counts are irregular, they track the episodic release of tectonic stress, not a smooth trend.
1 of 185 catalogued M4+ events since 2005 reached M6.0 or higher.
Magnitude distribution of major events
Breakdown of the 4 significant (M6+) earthquakes on record for Saint Helena.
M6.0-6.9
4
100.0%
Depth of major earthquakes
Hypocentral depth of the 4 M6+ events, shallow quakes shake the surface hardest. Average depth: 11 km.
Shallow (<70 km)
4
100.0% of events
Intermediate (70–300 km)
0
0.0% of events
Deep (>300 km)
0
0.0% of events
Strongest earthquakes in Saint Helena
The 4 most powerful events on record (USGS, since 1900).
| Mag | Location | Depth | Date |
|---|---|---|---|
| 6.1 | 144 km SSE of Georgetown, Saint Helena | 15.0 km | Mar 10, 1947 |
| 6.1 | 245 km ENE of Georgetown, Saint Helena | 10.0 km | Nov 8, 1922 |
| 6.0 | 221 km ENE of Georgetown, Saint Helena | 10.0 km | Aug 10, 2011 |
| 6.0 | 206 km NE of Georgetown, Saint Helena | 10.0 km | Mar 7, 2001 |
Significant earthquake record (4 events)
Every catalogued magnitude-6.0-and-above earthquake in Saint Helena since 1900, most recent first.
| Mag | Location | Depth | Date |
|---|---|---|---|
| 6.0 | 221 km ENE of Georgetown, Saint Helena | 10.0 km | Aug 10, 2011 |
| 6.0 | 206 km NE of Georgetown, Saint Helena | 10.0 km | Mar 7, 2001 |
| 6.1 | 144 km SSE of Georgetown, Saint Helena | 15.0 km | Mar 10, 1947 |
| 6.1 | 245 km ENE of Georgetown, Saint Helena | 10.0 km | Nov 8, 1922 |
Other countries in this catalog sample
A Saint Helena-keyed shuffle of the full 186-country roster, not the six nearest by count.
Peak-magnitude sample from the same roster
A second Saint Helena-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.