Fewer ‘significant’ earthquakes occurred worldwide in 1981 than in the previous year, according to the U.S. Geological Survey. Significant quakes are those that register 6.5 or more on the Richter scale and smaller ones that cause casualties or considerable damage.

Worldwide, there were 50 significant earthquakes in 1981, down from 71 in 1980; only two of 1981's significant seismic events shook the United States, down from 11 in 1980. The known death toll from earthquakes in 1981 was 5239, down from 7139 in 1980. Of the deaths in 1981, 4500 occurred in two separate quakes in Iran. No one has been killed by an earthquake in the United States since November 29, 1975.