Ground motion diagrams from pulse transmission through simple layered structures

Abstract

By computing theoretical seismograms and ground motion diagrams for assumed source, functions passed through simple layered models, it is possible qualitatively to reproduce ground motion patterns and apparent beat frequency patterns that characterize some long range seismic measurement (LRSM) recordings of underground nuclear explosions. Interference of overlapping phases may result in ambiguous arrival times for later phases. Ground motion diagrams are useful for identifying shear motion that is not obvious on seismograms.