CaltechAUTHORS
  A Caltech Library Service

Quantifying near-field and off-fault deformation patterns of the 1992 M_w 7.3 Landers earthquake

Milliner, Christopher W. D. and Dolan, James F. and Hollingsworth, James and Leprince, Sébastien and Ayoub, François and Sammis, Charles G. (2015) Quantifying near-field and off-fault deformation patterns of the 1992 M_w 7.3 Landers earthquake. Geochemistry, Geophysics, Geosystems, 16 (5). pp. 1577-1598. ISSN 1525-2027. https://resolver.caltech.edu/CaltechAUTHORS:20150710-144723707

[img] PDF - Published Version
See Usage Policy.

2651Kb
[img] MS Word - Supplemental Material
See Usage Policy.

3360Kb

Use this Persistent URL to link to this item: https://resolver.caltech.edu/CaltechAUTHORS:20150710-144723707

Abstract

Coseismic surface deformation in large earthquakes is typically measured using field mapping and with a range of geodetic methods (e.g., InSAR, lidar differencing, and GPS). Current methods, however, either fail to capture patterns of near-field coseismic surface deformation or lack preevent data. Consequently, the characteristics of off-fault deformation and the parameters that control it remain poorly understood. We develop a standardized method to fully measure the surface, near-field, coseismic deformation patterns at high resolution using the COSI-Corr program by correlating pairs of aerial photographs taken before and after the 1992 M_w 7.3 Landers earthquake. COSI-Corr offers the advantage of measuring displacement across the entire zone of surface deformation and over a wider aperture than that available to field geologists. For the Landers earthquake, our measured displacements are systematically larger than the field measurements, indicating the presence of off-fault deformation. We show that 46% of the total surface displacement occurred as off-fault deformation, over a mean deformation width of 154 m. The magnitude and width of off-fault deformation along the rupture is primarily controlled by the macroscopic structural complexity of the fault system, with a weak correlation with the type of near-surface materials through which the rupture propagated. Both the magnitude and width of distributed deformation are largest in stepovers, bends, and at the southern termination of the surface rupture. We find that slip along the surface rupture exhibits a consistent degree of variability at all observable length scales and that the slip distribution is self-affine fractal with dimension of 1.56.


Item Type:Article
Related URLs:
URLURL TypeDescription
http://dx.doi.org/10.1002/2014GC005693DOIArticle
ORCID:
AuthorORCID
Hollingsworth, James0000-0003-0122-296X
Leprince, Sébastien0000-0003-4555-8975
Ayoub, François0000-0002-7389-8400
Additional Information:© 2015 American Geophysical Union. Received 15 Dec 2014; Accepted 30 Mar 2015; Accepted article online 7 Apr 2015; Published online 27 May 2015. This research was funded by the US National Science Foundation (NSF EAR-1147436 grant to Dolan). We thank Amir Allabush for helpful discussions and reviews of an early draft of the paper and Jerry Treiman for his help in acquiring additional field measurements of the Landers earthquake. Finally we thank Mike Oskin, Ramon Arrowsmith and one anonymous reviewer for their help improving an earlier version of the manuscript. We thank the USGS for the EarthExplorer website (http://earthexplorer.usgs.gov/), which greatly simplified access to the aerial photographs used in this study. SPOT5 images were acquired from the coauthors S.L. and J.H.
Funders:
Funding AgencyGrant Number
NSFEAR-1147436
Subject Keywords:off-fault deformation; fault-width; COSI-Corr; Landers; slip distribution; fractal
Issue or Number:5
Record Number:CaltechAUTHORS:20150710-144723707
Persistent URL:https://resolver.caltech.edu/CaltechAUTHORS:20150710-144723707
Official Citation:Milliner, C. W. D., Dolan, J. F., Hollingsworth, J., Leprince, S., Ayoub, F., & Sammis, C. G. (2015). Quantifying near-field and off-fault deformation patterns of the 1992 Mw 7.3 Landers earthquake. Geochemistry, Geophysics, Geosystems, 16(5), 1577-1598. doi: 10.1002/2014gc005693
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:58855
Collection:CaltechAUTHORS
Deposited By: Joanne McCole
Deposited On:10 Jul 2015 22:48
Last Modified:13 Dec 2019 02:39

Repository Staff Only: item control page