Bulletin of the Seismological Society of America; April 1969; v. 59; no. 2;
p. 673-689
© 1969 Seismological Society of America
Application of strain seismographs to the discrimination of seismic waves
ROBERT C. SHOPLAND and
RICHARD H. KIRKLIN
GEOTECH A TELEDYNE COMPANY, 3401 SHILOH ROAD, GARLAND, TEXAS 75040
Abstract
Examination of microseisms recorded by strain and inertial seismographs at Wichita Mountains Observatory (WMO) has shown that the outputs of vertical strain and vertical inertial seismographs when combined through a linear filter do not provide a significant improvement of the signal-to-noise ratio in the frequency range 0.2 to 10 Hz. However, the ability of a combination of horizontal strain and inertial seismograph outputs to azimuthally discriminate between long-period surface waves arriving simultaneously from different epicenters is successfully demonstrated. The predicted response of strain seismometers to earth motion is verified by the existence of the proper phase and amplitude relationship, and high coherence among selected seismographs for single-source signals.
Copyright © 2009 by Seismological Society of America