Worldwide Collection and Interpretation of Earthquake Data. Seismicity Studies - Progress Report

摘要

The following objectives for accomplishment are given: To effect improvement in the accuracy of hypocenter determinations, particularly of depth; To investigate magnitude calculations and variations in earthquake magnitudes; To evaluate worldwide seismicity in 1964; To optimize determination of earthquake hypocenters, attempts were made to accumulate the maximum amount of available arrival-time data. Measurements of arrival times, periods and amplitudes of recorded events were made from 35-mm film copies of seismograms from 39 of the USC and GS worldwide stations and five of the Canadian seismograph stations operated by the Dominion Observatory in Toronto, Canada, and from short-period vertical records from Matsushiro, Japan. (Author)