1961 New South Wales earthquake

The 1961 New South Wales earthquake (also called the Robertson earthquake) occurred on 22 May in the Australian state of New South Wales (NSW). It reached a Richter magnitude of 5.5 and caused significant structural damage in a wide area.
The earthquake was felt from the Snowy Mountains region in the southeast of the state to Newcastle on the coast about north of Sydney; to Dubbo in central eastern NSW about northwest of Sydney; and to Narrandera in the state's central south about southwest of Dubbo — an estimated area of . In the area of Moss Vale, Robertson, and Bowral about southwest of Sydney, the earthquake caused significant structural damage to buildings, while rockfalls blocked the nearby Macquarie Pass. Sydney suffered minimal damage from the earthquake itself, though the tremors and resulting power failures caused "considerable alarm".
Seismograms at the Sydney suburb of Riverview were used to estimate the magnitude of the earthquake. There were only three known earthquakes of comparable magnitude prior to this one, occurring respectively in 1930, 1934 and 1938.
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