Analysis of P-Wave Residuals and Summary of Current Research

Brief summaries of work currently underway or completed during the period from 1 October 1977 to 31 December 1977 are given in four topic areas Source Studies, Data Analysis, Surface Wave Studies and Body Wave Studies. Also included in the report is a detailed description of a research project not previously reported. This study is entitled, Worldwide Observations of P-Wave Travel-Time Residuals. A large set of residuals compiled from ISC bulletins by Georges Poupinet of Institute de physique du Globe were compared with other data for the United States. The conclusions are that large negative residuals correlate with low heat flow and positive magnitude bias, and large positive residuals correlate with high heat flow and negative magnitude bias. The same correlation between heat flow and travel-time residuals holds for stations located on the Russian and Siberian Platforms in the U.S.S.R.