Jeffreys-Bullen seismological travel-time tables
Tablas de tiempos de viaje sísmicos de Jeffreys y Bullen
- Date
- 1935-1940 · confidence high
- Place
- Cambridge, England, United Kingdom
- Credited to
- Harold Jeffreys and Keith Bullen
- Field
- Cosmos & Earth
What it is
Jeffreys and Bullen calculated the times that P and S waves take to reach each distance from foci at different depths, from thousands of records. The JB tables were for more than four decades the reference for locating earthquakes around the world.
Preliminary tables were published in 1935; the definitive edition dates from 1940. The IASP91 model (1991) replaced them.
What it led to
- standardised earthquake location and world catalogues
- models of the Earth's internal structure