Quake surprised scientist, too

Press, 3 August 1976, Page 3

Quake surprised scientist, too

PA Wellington The superintendent of the Seismological Observatory (Dr R. D. Adams) expressed “some surprise” yesterday that the Chinese had not predicted the earthquake which flattened the coalmining city of Tangs’ last Wednesday. Dr Adams, who spent two weeks in China last year talking to seismologists, said the earthquake was close enough to Peking to be in the area covered by China’s most intensive network of seismological instruments.

Interest in Chinese seismological techniques heightened whe.s the Chinese successfully predicted the magnitude 7.3 earthquake that occurred near the town of Haicheng in North-east China on February 4 last year. Dr Adams said that one of the reasons why the Tangshan earthquake had not been predicted might have been connected with tne precursory time before earthquakes, during which various signs could often be detected.

“The length of this precursory time depends on the size of the earthquake. For small earthquakes, it is a few days or weeks. For larger earthquakes it is a few years. But it may be that last week’s earthquake was so large that the precursory time may have extended beyond the period in which the —..nese have

been looking for effects, and therefore they would have seen no changes.” Because of the generally higher building standards in New Zealand and other Western countries he did not consider earthquake prediction was as necessary here as in developing countries.

The earthquake which devastated Tangshan was magnitude 8 on the Richter scale. The last recorded earthquake of this magnitude in New Zealand occurred in south-west Wairarapa in 1855.