1983 Chagos Archipelago earthquake

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1983 Chagos Archipelago earthquake
Indian Ocean laea relief location map.jpg
Bullseye1.png
UTC  time1983-11-30 17:46:00
ISC  event 565767
USGS-ANSS ComCat
Local dateNovember 30, 1983 (1983-11-30)
Local time23:46
Magnitude7.7 Mw
7.7 Ms
Depth10 km (6.2 mi)
Epicenter 6°51′S72°07′E / 6.85°S 72.11°E / -6.85; 72.11
Max. intensity VI (Strong)

The 1983 Chagos Archipelago earthquake occurred on November 30 at 17:46 UTC (23:46 local time) in the region of the Chagos Archipelago, British Indian Ocean Territory. This earthquake had a moment magnitude and surface wave magnitude of 7.7. [1] This earthquake occurred in the Indian Plate near the Central Indian Ridge. The Central Indian Ridge is unusually active in near-ridge earthquakes. The intense seismic activity in this region may indicate an early stage of converging plate boundary, which is responsible for the N-S extension near Chagos. There was a 40 cm tsunami reported in Victoria, Seychelles. [2] [3]

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References

  1. ISC (2022), ISC-GEM Global Instrumental Earthquake Catalogue (1904–2018), Version 9.1, International Seismological Centre, doi: 10.31905/D808B825
  2. "Archived copy" (PDF). Archived from the original (PDF) on 2011-06-14. Retrieved 2010-10-16.{{cite web}}: CS1 maint: archived copy as title (link)
  3. "Significant Earthquakes of the World". Archived from the original on 2009-12-04.