Wave velocities at depths between 50 and 600 kilometers

Wave velocities in the interior of the earth are usually calculated by means of the Wiechert-Herglotz method. Incorrect interpretation of the form of the travel time curve for a certain distance interval then leads to errors not only in results concerning the corresponding depth interval but (in decreasing amounts) also for all greater depths. A new method is described and applied to that portion of the earth's mantle in which earthquake foci exist. Values obtained with this method for velocities at various depths are independent of each other