| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
U.S. GEOLOGICAL SURVEY, 345 MIDDLEFIELD ROAD, MENLO PARK, CALIFORNIA 94025
DEPT. OF GEOPHYSICS STANFORD UNIVERSITY, STANFORD, CALIFORNIA 94305
Abstract
A simple, uncontrived model of the rupture during the San Fernando earthquake can explain the main features of the particle velocity traces derived from the accelerograms recorded at Pacoima Dam. This result, combined with the probable small effect of surface topography on the velocity traces, strengthens the case for acceptance of the peak particle velocity at Pacoima Dam (115 cm/sec) as a valid ground-motion parameter for design purposes in earthquake engineering.
Most of the conspicuous motion on the velocity traces during the first 4 sec after triggering seems to result from thrust faulting, starting at a focal depth within several kilometers of 14 km, on a fault surface dipping at least 50° and extending only part way to the surface at a velocity near 2.5 km/sec. The data also indicate that this faulting continued to the surface at a slower rupture velocity (less than 2 km/sec) along a less steeply dipping surface.
The amount of relative offset across the fault surface is difficult to determine, both because of inherent limitations in the two-dimensional model and because of nonuniqueness in the fitting of the data. The estimates of this dislocation, however, are consistent with the wide range of values reported by other authors in studies using various types of data. The data are also consistent with a model suggested by Alewine and Jordan (1973) and Trifunac (1974) in which the total dislocation has a minimum near the center of the fault surface, with approximately equal amounts of total offset on the fault near the hypocenter and near the Earth's surface.
This article has been cited by other articles:
|
|
 |
|
  An Observation of Rupture Pulses of the 20 September 1999 Chi-Chi, Taiwan, Earthquake from Near-Field Seismograms Bulletin of the Seismological Society of America, October 1, 2004; 91(5): 1247 - 1254.
|
|
|
|
|
|
G. P. Mavroeidis and A. S. Papageorgiou A Mathematical Representation of Near-Fault Ground Motions Bulletin of the Seismological Society of America, June 1, 2003; 93(3): 1099 - 1131. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. S. PAPAGEORGIOU and K. AKI A specific barrier model for the quantitative description of inhomogeneous faulting and the prediction of strong ground motion. Part II. Applications of the model Bulletin of the Seismological Society of America, August 1, 1983; 73(4): 953 - 978. [Abstract] [PDF]
|
|
|
|
|
|
J. ENRIQUE LUCO and J. G. ANDERSON Steady-state response of an elastic half-space to a moving dislocation of finite width Bulletin of the Seismological Society of America, February 1, 1983; 73(1): 1 - 22. [Abstract] [PDF]
|
|
|
|
|
|
J. G. ANDERSON and J. E. LUCO Parametric study of near-field ground motions for oblique-slip and dip-slip dislocation models Bulletin of the Seismological Society of America, February 1, 1983; 73(1): 45 - 57. [Abstract] [PDF]
|
|
|
|
|
|
D. M. BOORE, W. B. JOYNER, A. A. OLIVER III, and R. A. PAGE Peak acceleration, velocity, and displacement from strong-motion records Bulletin of the Seismological Society of America, February 1, 1980; 70(1): 305 - 321. [Abstract] [PDF]
|
|
|
|
|
|
M. BOUCHON A dynamic source model for the San Fernando earthquake Bulletin of the Seismological Society of America, December 1, 1978; 68(6): 1555 - 1576. [Abstract] [PDF]
|
|
|
|
|
|
R. DOBRY, I. M. IDRISS, and E. NG Duration characteristics of horizontal components of strong-motion earthquake records Bulletin of the Seismological Society of America, October 1, 1978; 68(5): 1487 - 1520. [Abstract] [PDF]
|
|
|
|
|
|
C. A. LANGSTON The February 9, 1971 San Fernando earthquake: A study of source finiteness in teleseismic body waves Bulletin of the Seismological Society of America, February 1, 1978; 68(1): 1 - 29. [Abstract] [PDF]
|
|
|
|
|
|
M. BOUCHON and K. AKI Discrete wave-number representation of seismic-source wave fields Bulletin of the Seismological Society of America, April 1, 1977; 67(2): 259 - 277. [Abstract] [PDF]
|
|
|
|
|
|
R. J. GELLER Scaling relations for earthquake source parameters and magnitudes Bulletin of the Seismological Society of America, October 1, 1976; 66(5): 1501 - 1523. [Abstract] [PDF]
|
|
|
|
|
|
M. OHNAKA A physical basis for earthquakes based on the elastic rebound model Bulletin of the Seismological Society of America, April 1, 1976; 66(2): 433 - 451. [Abstract] [PDF]
|
|
|
|
|
|
A. NIAZY An exact solution for a finite, two-dimensional moving dislocation in an elastic half-space with application to the San Fernando earthquake of 1971 Bulletin of the Seismological Society of America, December 1, 1975; 65(6): 1797 - 1826. [Abstract] [PDF]
|
|
|
|
|
|
W. B. JOYNER A method for calculating nonlinear seismic response in two dimensions Bulletin of the Seismological Society of America, October 1, 1975; 65(5): 1337 - 1357. [Abstract] [PDF]
|
|
|
|
|
|
D. A. RODGERS Comments on "The San Fernando Earthquake and Public School Safety" by D. E. Hudson and D. K. Jephcott Bulletin of the Seismological Society of America, October 1, 1975; 65(5): 1507 - 1508. [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
