|Origin time 03:40 UTC+09:30|
Areas affected Australia
Depth 4,000 m
|Magnitude 5.6 Mw|
Fault Eden-Burnside Fault
Date 1 March 1954
The 1954 Adelaide earthquake had its center at Darlington, some 12 km (7.5 mi) to the south of Adelaide in South Australia. It took place at 03.40 in the early morning of 1 March 1954 and had a reported magnitude of 5.6. The quake is thought to have started along the Eden-Burnside fault line, which is essentially the Hills face zone, at a depth of 4 km although, due to lack of instruments, this is uncertain.
As Australia lies in the middle of a tectonic plate, South Australia is relatively stable geologically, however, South Australia is the second most earthquake prone of the Australian states with around 3-4 tremors every day. Most are, however, of a magnitude below 2.5 noteworthy only to seismologists, and since they are dispersed fairly evenly across the state, most take place well away from centers of human population. The 1954 Adelaide earthquake was different because of its magnitude, which made it the fourth most intense earthquake reported in the state since settlement in 1836, and because it took place in an area of dense human settlement, under a suburb of the state capital, Adelaide.
An area of more than 700 km² sustained an intensity greater than V. Due to the Adelaide plains being primarily heavy clay, amplification of the tremor was reduced, resulting in less damage than a quake of this size would normally be expected to cause in a metropolitan area. There were no reported fatalities and 16 reported injuries.
One of the settlement’s earliest buildings, the Victoria Hotel, suffered partial collapse. Other major buildings severely damaged included the local church, St Francis Xavier Cathedral, the Adelaide Post Office clock tower and a newly completed hospital in Blackwood which sustained major damage in all its wards and offices (though an operating theatre survived). The Britannia statue in Pirie Street, Adelaide was badly damaged, and since it had also been similarly damaged in the 1897 Beachport and 1902 Warooka earthquakes, the clock in the statue was permanently removed.
Outside of Adelaide there was little damage. The Troubridge Island Lighthouse off the south east corner of Yorke Peninsula 83 km west of Adelaide across the Gulf St Vincent shut down after the quake damaged its generator while the Cape St. Albans Lighthouse on Kangaroo Island began flashing irregularly.
The total cost of damage was estimated at around £17 million (2010: $500 million) but only £3 million (2010:$90 million) was paid out in insurance for 30,303 claims covering around 22% of the damaged buildings. Adelaide in 1954 was still subject to wartime rationing, and most of the damaged property was not insured.
This earthquake was Australia's most destructive until it was eclipsed by the 5.6 Richter magnitude Newcastle earthquake in 1989 which caused $4 billion damage, killed 13 people and injured 160.