The International Seismological Summary

Abstract

THE International Seismological Summary for the second quarter of 1934 has just been received. It contains the determinations of 144 epicentres by the workers at Oxford, from all the available evidence sent by Seismological observatories, throughout the world. Sixty–two of these epicentres are new and eighty–two are repetitions from old epicentres, again showing the tendency of earthquakes to recur. Fifteen of the earthquakes have deeper focus than normal and one on June 29, 1934, at 8h. 25m. 20s. G.M.T.,has a calculated focus 0.106 of the earth's radius below normal, which is at a greater depth than that of any earthquake previously treated in the summary. The epicentre of this shock was at 6.1°S., 123.4°E., which is in the Banda Sea close to and immediately east of the town of Baoebaoe in the island of Celebes in the Dutch East Indies. The area is well known to be frequented by deep focus earthquakes. In view of the accuracy with which the epicentre is known, the numerous data have been used to extend a table of corrections which may be applied to epicentral distances to produce agreement between observed and calculated times of the P wave.