Wadati
Wadati refers to Kiyoo Wadati, a Japanese seismologist whose work laid important foundations for the understanding of earthquake depth and subduction zones. His research contributed to the development of methods for determining the focal depth of earthquakes and to early evidence for deep seismicity beneath ocean trenches. The Wadati diagram, named for him, is a graphical method for estimating earthquake depth by analyzing the arrival times of P- and S-waves recorded at seismographs.
In the 1930s, Wadati identified a pattern of earthquake foci that extended from shallow to several hundred
Wadati's work thus contributed to a new understanding of global plate interactions and the dynamic processes