CaltechAUTHORS
  A Caltech Library Service

An anisotropic contrast in the lithosphere across the central San Andreas fault

Jiang, Chengxin and Schmandt, Brandon and Clayton, Robert W. (2018) An anisotropic contrast in the lithosphere across the central San Andreas fault. Geophysical Research Letters, 45 (9). pp. 3967-3975. ISSN 0094-8276. https://resolver.caltech.edu/CaltechAUTHORS:20180501-112233586

[img] PDF - Published Version
See Usage Policy.

1422Kb
[img] PDF (Figure S1) - Supplemental Material
See Usage Policy.

4Mb

Use this Persistent URL to link to this item: https://resolver.caltech.edu/CaltechAUTHORS:20180501-112233586

Abstract

Seismic anisotropy of the lithosphere and asthenosphere was investigated with a dense broadband seismic transect nearly orthogonal to the central San Andreas fault (SAF). A contrast in SK(K)S splitting was found across the SAF, with a clockwise rotation of the fast orientation ~26° closer to the strike of the SAF and greater delay times for stations located within 35 km to the east. Dense seismograph spacing requires heterogeneous anisotropy east of the SAF in the uppermost mantle or crust. Based on existing station coverage, such a contrast in splitting orientations across the SAF may be unusual along strike and its location coincides with the high‐velocity Isabella anomaly in the upper mantle. If the Isabella anomaly is a fossil slab fragment translating with the Pacific plate, the anomalous splitting east of the SAF could indicate a zone of margin‐parallel shear beneath the western edge of North America.


Item Type:Article
Related URLs:
URLURL TypeDescription
https://doi.org/10.1029/2018GL077476DOIArticle
https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2018GL077476PublisherArticle
ORCID:
AuthorORCID
Jiang, Chengxin0000-0002-8768-2782
Schmandt, Brandon0000-0003-1049-9020
Clayton, Robert W.0000-0003-3323-3508
Additional Information:© 2018 American Geophysical Union. Received 5 FEB 2018; Accepted 20 APR 2018; Accepted article online 30 APR 2018; Published online 9 MAY 2018. CCSE seismic data are publicly available via the IRIS DMC (http://ds.iris.edu/ds/nodes/dmc/), network code TO 2013‐2015 (CCSE, 2013). This research was supported by NSF‐EAR 1315856 and 1554908, and the seismic instruments used were acquired with support from the Gordon and Betty Moore Foundation. Two anonymous reviewers and the Editor Gavin Hayes are thanked for their constructive feedback.
Group:Seismological Laboratory
Funders:
Funding AgencyGrant Number
NSFEAR-1315856
NSFEAR-1554908
Gordon and Betty Moore FoundationUNSPECIFIED
Subject Keywords:central California; SKS splitting; fault‐parallel anisotropy; Isabella anomaly
Issue or Number:9
Record Number:CaltechAUTHORS:20180501-112233586
Persistent URL:https://resolver.caltech.edu/CaltechAUTHORS:20180501-112233586
Official Citation:Jiang, C., Schmandt, B., & Clayton, R. W. (2018). An anisotropic contrast in the lithosphere across the central San Andreas fault. Geophysical Research Letters, 45, 3967–3975. https://doi.org/10.1029/2018GL077476
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:86154
Collection:CaltechAUTHORS
Deposited By: Tony Diaz
Deposited On:01 May 2018 19:39
Last Modified:03 Oct 2019 19:40

Repository Staff Only: item control page