Research at the meteorological observatory
Wadati studied physics at Tokyo Imperial University. The 1923 Kantō earthquake helped turn his interests towards meteorology and seismology; in 1925 he joined the Central Meteorological Observatory.
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Evidence for deep earthquakes
Comparing P–S arrival intervals and their spatial distribution, he demonstrated earthquakes deeper than 300 kilometres in 1927. In 1935 he mapped an inclined zone of deep foci, later associated with the Wadati–Benioff zone extending from trenches beneath land.
References: [1]
Public science
His work expanded to land subsidence and administration. He became the new Japan Meteorological Agency’s first director-general in 1956 and led the National Research Center for Disaster Prevention from 1963 to 1966.
References: [1]