On February 4, 1975, an earthquake measuring 7.3 on the Richter Scale rocked Haicheng, Liaoning province. Thankfully the death count was low, Chinese authorities having ordered an enforced evacuation of homes in what is widely cited as the first earthquake successfully predicted.
A study of seismic activity in the previous months and a number of foreshocks the previous day led to the decision, apparently, a move authorities credited with keeping the death toll under 300, where tens of thousands of fatalities might have been expected. Or so the story goes...
Occuring as it did during the Cultural Revolution, record keeping was disordered. And the failure of officials to predict the devastating 7.8 magnitude
Tangshan Earthquake a year later, which killed some 240,000 people, led
many to question the the prediction claim (belief in earthquake prediction became an element of ideological orthodoxy that distinguished true party liners from right wing deviationists).
In 2006, a group of international scientists were given access to records and key witnesses. Their report found that there was no official short-term prediction, although there were by individual scientists, “a blend of confusion, empirical analysis, intuitive judgment and good luck,” and that “it was the foreshocks alone that triggered the final decisions of warning and evacuation.”
The light loss of life - which they set higher than 300 at 2,041 - was attributed to a number of fortuitous circumstances, including earthquake education in previous months, the fact it occurred at 7.36pm, when people were neither working nor asleep, and the durable style of housing construction in the area.
So perhaps not such an earth-shattering event as was previously claimed...
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