The 1933 Baffin Bay earthquake

Location and Magnitude

  • Local Date and Time: November 20, 1933 at 6:21:32 pm Eastern time
  • UT Date and Time: 1933-11-20 23:21:32 UT
  • Magnitude: MW 7.3-7.4; MS 7.3; mB 7.2
  • Latitude: 73.0° N
  • Longitude: 70.75° W
  • Depth: 10 km

This earthquake is the largest instrumentally recorded earthquake to have occurred along the passive margin of North America and coincidentally is also the largest known earthquake north of the Arctic Circle. In spite of its size, the 1933 earthquake did not result in any damage because of its offshore location and the sparse population of the adjacent onshore regions.

The only known location that felt the earthquake was in the Upernavik, Greenland region (see map below) while it was definitely not felt in Thule to the north or in Diskofjord to the south. One would have expected the earthquake to have shaken the closer northeastern coastal communities of Baffin Island but no felt reports were ever collected from northern Canada.

The northwestern Baffin Bay -northeastern Baffin Island region continues to be active, one of the most active regions in eastern Canada. 5 magnitude 6 earthquakes have occurred here since the 1933 earthquake. The latest moderate-sized earthquake was a magnitude 5.1 event on April 15, 2010.

Baffin Bay seismicity

Reference

  • Allison L. Bent, 2002. The 1933 Ms = 7.3 Baffin Bay earthquake: strike-slip faulting along the northeastern Canadian passive margin. Geophysical Journal International, v 150, p 724-736. pdf document, 600Kb