Saint Helena earthquakes in 1987
21 earthquakes of magnitude 4.5 or more were located in Saint Helena in 1987. The largest: M5.6 north of Ascension Island, Jun 30, 1987.
From the USGS catalog. Times are local to each quake.
Map
Where every quake of 1987 was located in Saint Helena. Select one for its page.
Every quake of 1987
Magnitude 4.5 and up, newest first.
- 4.9north of Ascension Island · 10 km deep
- 4.9north of Ascension Island · 10 km deep
- 5.0north of Ascension Island · 10 km deep
- 5.6north of Ascension Island · 10 km deep
- 4.7north of Ascension Island · 10 km deep
- 4.6209 km ENE of Georgetown, Saint Helena · 10 km deep
- 4.7north of Ascension Island · 10 km deep
- 4.7north of Ascension Island · 10 km deep
- 4.8158 km WNW of Jamestown, Saint Helena · 10 km deep
- 4.7north of Ascension Island · 10 km deep
- 4.9Ascension Island region · 10 km deep
- 4.8north of Ascension Island · 10 km deep
- 5.6north of Ascension Island · 10 km deep
- 4.9north of Ascension Island · 10 km deep
- 4.9Ascension Island region · 10 km deep
- 5.1Ascension Island region · 10 km deep
- 4.9Ascension Island region · 10 km deep
- 4.7Ascension Island region · 10 km deep
- 5.0Ascension Island region · 10 km deep
- 5.2Ascension Island region · 10 km deep
- 4.9north of Ascension Island · 10 km deep
Month by month
Counted by UTC date, which is how the catalog files them.
| Month | Quakes | Largest | Where |
|---|---|---|---|
| January 1987 | 8 | 5.2 | Ascension Island region |
| February 1987 | 1 | 5.6 | north of Ascension Island |
| March 1987 | 2 | 4.9 | Ascension Island region |
| April 1987 | 1 | 4.7 | north of Ascension Island |
| May 1987 | 3 | 4.8 | 158 km WNW of Jamestown, Saint Helena |
| June 1987 | 3 | 5.6 | north of Ascension Island |
| July 1987 | 0 | ||
| August 1987 | 0 | ||
| September 1987 | 2 | 5.0 | north of Ascension Island |
| October 1987 | 0 | ||
| November 1987 | 1 | 4.9 | north of Ascension Island |
| December 1987 | 0 |
What this means
The catalog is only as complete as the instruments of the time. Worldwide coverage of magnitude 5 and up dates from the 1960s, and of 4.5 from the 1990s; earlier years hold the large quakes and the ones near a station, so a low count in an early year means fewer instruments, not a quiet earth.
By year
Every year the USGS catalog covers.
- 2020s2020202120222023202420252026
- 2010s2010201120122013201420152016201720182019
- 2000s2000200120022003200420052006200720082009
- 1990s1990199119921993199419951996199719981999
- 1980s1980198119821983198419851986198719881989
- 1970s1970197119721973197419751976197719781979
- 1960s1960196119621963196419651966196719681969
- 1950s1950195119521953195419551956195719581959
- 1940s1940194119421943194419451946194719481949
- 1930s1930193119321933193419351936193719381939
- 1920s1920192119221923192419251926192719281929
- 1910s1910191119121913191419151916191719181919
- 1900s1900190119021903190419051906190719081909
Nearby
Sources
Earthquakes, magnitudes, depths, shaking estimates and felt reports from the U.S. Geological Survey Earthquake Hazards Program, read from its live feeds and its catalog back to 1900. Tsunami messages from NOAA’s tsunami warning centers.