Professor Kiyoo Wadati (和達清夫) was an early seismologist at the Central Meteorological Observatory of Japan, researching deep (subduction zone) earthquakes. His name is attached to the Wadati-Benioff zone. It was Wadati's 1928 paper on shallow and deep earthquakes, comparing maximum surface displacement against distance from the epicentre, which lead Charles Richter to develop his earthquake magnitude scale in 1935.