| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
UNITED STATES GEOLOGICAL SURVEY SEISMOLOGY BRANCH CALIFORNIA INSTITUTE OF TECHNOLOGY, PASADENA, CALIFORNIA 91125
Abstract
Broadband vertical P-wave records are analyzed from 63 of the largest shallow subduction zone earthquakes which have occurred in the circum-Pacific in the last 45 yr. Most of the records studied come from a common instrument, the Pasadena, California, Benioff 1-90 seismometer. Propagation and instrument effects are deconvolved from the P-wave records using a damped least-squares inversion to obtain the teleseismic source time function. The inversion has the additional constraint that the time function be positive everywhere. The period band over which the time functions are considered reliable is from 2.5 to 50 sec. Fourier displacement amplitude spectra computed for each of the 1-90 P-wave trains indicate spectral slopes measured between 2 and 50 sec of 
–1.0 to –2.25 with an average value of –1.5. These values assume an average attenuation of t* = 1.0. The seismic moments derived from the P-wave time functions compare well with other published values for earthquakes having moments smaller than 2.5 x 1028 dyne-cm (Mw = 8.2). Because the 1-90 seismometer has little response at very long periods, this technique underestimates the moments of the very largest events. The time functions are characterized using five parameters: (1) spectral slope between 2 and 50 sec; (2) roughness of the time function; (3) multiplicity of sources; (4) pulse widths of individual sources; and (5) overall signal duration. The 63 earthquakes studied come from 15 subduction zones with a wide range in the ages of subducted lithosphere, convergence rates, and maximum size of earthquakes. Comparing the time function parameters with age, rate, and Mw of the subduction zone does not yield obvious global trends. However, most of the subduction zones do behave characteristically and can be grouped accordingly.
This article has been cited by other articles:
|
|
 |
|
  P. Bernard, P. Bernard, A. Herrero, and C. Berge Modeling directivity of heterogeneous earthquake ruptures Bulletin of the Seismological Society of America, August 1, 1996; 86(4): 1149 - 1160. [Abstract] [PDF]
|
|
|
|
|
|
A. Herrero and P. Bernard A kinematic self-similar rupture process for earthquakes Bulletin of the Seismological Society of America, August 1, 1994; 84(4): 1216 - 1228. [Abstract] [PDF]
|
|
|
|
|
|
R. Abercrombie and J. Mori Local observations of the onset of a large earthquake: 28 June 1992 Landers, California Bulletin of the Seismological Society of America, June 1, 1994; 84(3): 725 - 734. [Abstract] [PDF]
|
|
|
|
|
|
A. A. Velasco, C. J. Ammon, and T. Lay Empirical green function deconvolution of broadband surface waves: Rupture directivity of the 1992 Landers, California (Mw = 7.3), earthquake Bulletin of the Seismological Society of America, June 1, 1994; 84(3): 735 - 750. [Abstract] [PDF]
|
|
|
|
|
|
H. KANAMORI, P. C. JENNINGS, S. K. SINGH, and L. ASTIZ Estimation of strong ground motions in Mexico City expected for large earthquakes in the Guerrero seismic gap Bulletin of the Seismological Society of America, June 1, 1993; 83(3): 811 - 829. [Abstract] [PDF]
|
|
|
|
|
|
S. H. HARTZELL Estimation of near-source ground motions from a teleseismically derived rupture model of the 1989 Loma Prieta, California, earthquake Bulletin of the Seismological Society of America, October 1, 1992; 82(5): 1991 - 2013. [Abstract] [PDF]
|
|
|
|
|
|
A. J. MENDEZ and J. G. ANDERSON The temporal and spatial evolution of the 19 September 1985 Michoacan earthquake as inferred from near-source ground-motion records Bulletin of the Seismological Society of America, June 1, 1991; 81(3): 844 - 861. [Abstract] [PDF]
|
|
|
|
|
|
L. WENNERBERG Stochastic summation of empirical Green's functions Bulletin of the Seismological Society of America, December 1, 1990; 80(6A): 1418 - 1432. [Abstract] [PDF]
|
|
|
|
|
|
C. MENDOZA and S. H. HARTZELL Inversion for slip distribution using teleseismic P waveforms: North Palm Springs, Borah Peak, and Michoacan earthquakes Bulletin of the Seismological Society of America, June 1, 1988; 78(3): 1092 - 1111. [Abstract] [PDF]
|
|
|
|
|
|
S. H. HARTZELL and T. H. HEATON Failure of self-similarity for large (M{omega} > Formula) earthquakes Bulletin of the Seismological Society of America, April 1, 1988; 78(2): 478 - 488. [Abstract] [PDF]
|
|
|
|
|
|
C. B. CROUSE, Y. K. VYAS, and B. A. SCHELL Ground motions from subduction-zone earthquakes Bulletin of the Seismological Society of America, February 1, 1988; 78(1): 1 - 25. [Abstract] [PDF]
|
|
|
|
 |
|
 T. H. Heaton, T. H. HEATON, and S. H. HARTZELL Earthquake Hazards on the Cascadia Subduction Zone Science, April 10, 1987; 236(4798): 162 - 168. [Abstract] [PDF]
|
|
|
|
|
|
Y. ZHUO and H. KANAMORI Regional variation of the short-period (1 to 10 second) source spectrum Bulletin of the Seismological Society of America, April 1, 1987; 77(2): 514 - 529. [Abstract] [PDF]
|
|
|
|
|
|
T. H. HEATON and S. H. HARTZELL Source characteristics of hypothetical subduction earthquakes in the northwestern United States Bulletin of the Seismological Society of America, June 1, 1986; 76(3): 675 - 708. [Abstract] [PDF]
|
|
|
|
|
|
H. HOUSTON and H. KANAMORI Source spectra of great earthquakes: Teleseismic constraints on rupture process and strong motion Bulletin of the Seismological Society of America, February 1, 1986; 76(1): 19 - 42. [Abstract] [PDF]
|
|
|
|
|
|
D. M. BOORE Short-period P- and S-wave radiation from large earthquakes: Implications for spectral scaling relations Bulletin of the Seismological Society of America, February 1, 1986; 76(1): 43 - 64. [Abstract] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
