wikipedia - 27 Nov 2022
An earthquake occurred in southern Mongolia on December 4, 1957, measuring Mw 7.8–8.1 and assigned XII (Extreme) on the Modified Mercalli intensity scale. Surface faulting was observed in the aftermath with peak vertical and horizontal scarp reaching 9 m (30 ft). Because of the extremely sparse population in the area, this event, despite its magnitude, was not catastrophic. However, 30 people died and the towns of Dzun Bogd, Bayan-leg and Baruin Bogd were completely destroyed.
