HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) References Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by HASEGAWA, H. S. Search for Related Content GeoRef GeoRef Citation

Surface- and body-wave spectra of CANNIKIN and shallow Aleutian earthquakes

DIVISION OF SEISMOLOGY EARTH PHYSICS BRANCH DEPARTMENT OF ENERGY, MINES AND RESOURCES, OTTAWA, ONTARIO, KIA OE4, Canada

Abstract

Rayleigh waves and P codas of CANNIKIN and shallow Aleutian earthquakes are studied in order to determine the parameters most influential in shaping the respective teleseismic amplitude spectra and in governing the surface (M_S) and bodywave (m_b) magnitudes. For surface-wave generation, the dipole strength (P_o) of the underground nuclear explosion, and the seismic moment (M_o) of the earthquake are the important parameters. The M_S for these events are comparable when M_o is approximately 3 to 4 times greater than P_o. Theoretical considerations of bodywave spectra indicate that the important parameters are the permanent offset in the reduced displacement potential [()] of explosions and the product of area of faulting (S) and average dislocation () of earthquakes. These source parameters are related by P_o = 4( + 2µ) () and M_o = µ S where and µ are the elastic Lamé parameters. An additional parameter, namely, the peak frequency (f_p) in the explosion P-coda spectrum and the corner frequency (f_c) in the earthquake spectrum, is of paramount importance in determining the respective m_b. For the events considered, f_p is from 5 to 10 times greater than f_c and this is manifest in the corresponding m_b, where the m_b for CANNIKIN is at least a unit greater than that of the earthquakes. The linear dimensions of the respective sources appear to exert a major influence upon f_c and f_p.

The large scatter between theoretical and actual m_b values, unfortunately, precludes a firm confirmation of the above theoretical considerations.

This article has been cited by other articles:

				H. PULPAN and C. FROHLICH Geometry of the subducted plate near Kodiak Island and Lower Cook Inlet, Alaska, determined from relocated earthquake hypocenters Bulletin of the Seismological Society of America, June 1, 1985; 75(3): 791 - 810. [Abstract] [PDF]

				T. LAY, D. V. HELMBERGER, and D. G. HARKRIDER Source models and yield-scaling relations for underground nuclear explosions at Amchitka Island Bulletin of the Seismological Society of America, June 1, 1984; 74(3): 843 - 862. [Abstract] [PDF]

				J. LAWTON, C. FROHLICH, H. PULPAN, and G. V. LATHAM Earthquake activity at the Kodiak continental shelf, Alaska, determined by land and ocean bottom seismograph networks Bulletin of the Seismological Society of America, February 1, 1982; 72(1): 207 - 220. [Abstract] [PDF]

				R. B. HORNER, A. E. STEVENS, H. S. HASEGAWA, and G. LEBLANC Focal parameters of the July 12, 1975, Maniwaki, Quebec, earthquake--An example of intraplate seismicity in eastern Canada Bulletin of the Seismological Society of America, June 1, 1978; 68(3): 619 - 640. [Abstract] [PDF]

				T. C. BACHE and D. G. HARKRIDER The body waves due to a general seismic source in a layered earth model: 1. Formulation of the theory Bulletin of the Seismological Society of America, December 1, 1976; 66(6): 1805 - 1819. [Abstract] [PDF]

				R. B. HERRMANN and B. J. MITCHELL Statistical analysis and interpretation of surface-wave anelastic attenuation data for the stable interior of North America Bulletin of the Seismological Society of America, October 1, 1975; 65(5): 1115 - 1128. [Abstract] [PDF]