Seismic P-waves from Novaya Zemlya explosions: seeing double!

• Published in: Geophysical Journal International
• Main Authors: Stewart, R. C., Marshall, P. D.
• Format: Text
• Language: English
• Published: Oxford University Press 1988
• Subjects: Research Note; Novaya Zemlya
• Online Access: http://gji.oxfordjournals.org/cgi/content/short/92/2/335; https://doi.org/10.1111/j.1365-246X.1988.tb01144.x

The P -wave seismograms generated by an underground explosion on 11 October, 1980 at the northern Novaya Zemlya test site are quite different from the seismograms normally recorded from explosions there. However, the PcP seismograms are similar to the PcPs normally observed. A simple deconvolution of the seismograms yields pulse shapes that are interpreted as being generated by two simultaneous explosions, some 7 km apart. The spatial separation causes the appearance of the P -wave seismograms to change with azimuth, but such variation is not observed in PcP because the steeply-descending wavefronts from each explosion are superpositioned. The observed P -wave seismograms from the double explosions are successfully modelled using the observed PcP as the source function.