A Seismic Model Study of Elastic Radiations from Spherical Wave-Sources

Abstract

A seismic model study is made to confirm the theoretical results of elastic radiations from spherical wave-sources in our past paper.
A two dimensional substitute for the theoretical source is prepared and firstly estimated, in the apparatus Fig. 3 (A), about its practical possibility to be employed as a directive source. The homogeneity of the medium (plate of acrlite) is also examined through the same apparatus. The pressure-time variation at the source, p(t), is numerically obtained from the Fourier spectra of seismic records of initial P pulse in the apparatus Fig. 3 (B), by which the wave-forms of initial P are also recorded in several directions for three kinds of directive sources. The initial SV pulses radiated from these directive sources are investigated by the apparatus Fig. 3 (C). The P and SV pulses thus recorded are compared with the calculated ones whose source function is chosen as p(t). Agreement of both results is perceived to a considerable extent.