1957 December 04 03:37 UTC
Thirty deaths. All houses were destroyed in Dzun Bogd and Bayan Gobi. Subsidence, faulting and fissures occurred in the Bahar Uula and Ih Bogd Uul Mountains. The largest fissure was 250 km (155 mi) long with as much as 9-11 m (30-36 ft) of vertical and 3 m (10 ft) of horizontal offset. Because of the extremely sparse population in the area, this is perhaps the least damaging great earthquake to have occurred on land in the 20th Century; the direct opposite of the Agadir, Morocco earthquake of 29 Feb 1960.