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Saint Helena earthquakes in 1977

9 earthquakes of magnitude 4.5 or more were located in Saint Helena in 1977. The largest: M5.5 Tristan da Cunha region, Oct 14, 1977.

From the USGS catalog. Times are local to each quake.

19761978

Map

Where every quake of 1977 was located in Saint Helena. Select one for its page.

Open the live map with earthquakes

Every quake of 1977

Magnitude 4.5 and up, newest first.

Month by month

Counted by UTC date, which is how the catalog files them.

MonthQuakesLargestWhere
January 197715.0Tristan da Cunha region
February 197715.5Ascension Island region
March 197725.3north of Ascension Island
April 197715.0Ascension Island region
May 197714.7122 km NE of Georgetown, Saint Helena
June 19770
July 197725.3north of Ascension Island
August 19770
September 19770
October 197715.5Tristan da Cunha region
November 19770
December 19770

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.

Nearby

Saint Helena nowWorldwide in 1977

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.