A Caltech Library Service

Fault-Zone Waves Observed at the Southern Joshua Tree Earthquake Rupture Zone

Hough, S. E. and Ben-Zion, Y. and Leary, P. (1994) Fault-Zone Waves Observed at the Southern Joshua Tree Earthquake Rupture Zone. Bulletin of the Seismological Society of America, 84 (3). pp. 761-767. ISSN 0037-1106.

PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


Waveform and spectral characteristics of several aftershocks of the M 6.1 22 April 1992 Joshua Tree earthquake recorded at stations just north of the Indio Hills in the Coachella Valley can be interpreted in terms of waves propagating within narrow, low-velocity, high-attenuation, vertical zones. Evidence for our interpretation consists of: (1) emergent P arrivals prior to and opposite in polarity to the impulsive direct phase; these arrivals can be modeled as headwaves indicative of a transfault velocity contrast; (2) spectral peaks in the S wave train that can be interpreted as internally reflected, low-velocity fault-zone wave energy; and (3) spatial selectivity of event-station pairs at which these data are observed, suggesting a long, narrow geologic structure. The observed waveforms are modeled using the analytical solution of Ben-Zion and Aki (1990) for a plane-parallel layered fault-zone structure. Synthetic waveform fits to the observed data indicate the presence of NS-trending vertical fault-zone layers characterized by a thickness of 50 to 100 m, a velocity decrease of 10 to 15% relative to the surrounding rock, and a P-wave quality factor in the range 25 to 50.

Item Type:Article
Related URLs:
URLURL TypeDescription
Ben-Zion, Y.0000-0002-9602-2014
Additional Information:© 1994, by the Seismological Society of America. Manuscript received 18 August 1993. We gratefully acknowledge the cooperation and patience of the homeowners who allowed us to deploy instruments on their property. We thank E. Sembera, C. Mueller, G. Glassmoyer, L. Wennerberg, and S. Lydeen for their efforts in instrument deployment, maintenance, and data processing. We thank Jim Moil, Tom Heaton, and an anonymous reviewer for reviews of the manuscript, and M. Rymer for his review and helpful discussions.
Issue or Number:3
Record Number:CaltechAUTHORS:20140806-100144966
Persistent URL:
Official Citation:S. E. Hough, Y. Ben-Zion, and P. Leary Fault-zone waves observed at the southern Joshua Tree earthquake rupture zone Bulletin of the Seismological Society of America, June 1994, v. 84, p. 761-767
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:48060
Deposited By: Ruth Sustaita
Deposited On:06 Aug 2014 17:07
Last Modified:03 Oct 2019 06:59

Repository Staff Only: item control page