Velocity of P waves in the earth calculated from the Macelwane P curve, 1933*

Abstract

Summary The Macelwane P curve is based on the data of the Tango, Hawke Bay, and Long Beach earthquakes, all of 10–12 km. focal depth. This curve was modified and adjusted to fit a spheroid of 6355 km. radius, the outer part of which has the same properties as those immediately under the Mohorovičić discontinuity in Japan. The original and the adjusted P curve are given as well as the velocity-depth and depth-distance data obtained by applying the Herglotz-Wiechert method to the adjusted P curve. The inversion and slight decrease of the velocity-depth function at 2730 km. depth are discussed and the continued validity of the Herglotz-Wiechert method under those circumstances is shown.