@article{23b0eee5dbf246cf80ea2f55b30a5282,
title = "The Deformational Journey of the Nazca Slab From Seismic Anisotropy",
abstract = "The Andean subduction zone is an excellent place to study deformation within a subducting slab as a function of depth, owing to the varying and well-resolved geometry of the subducting Nazca slab beneath South America. Here we combine the results of source-side shear wave splitting with the latest regional tomography model to isolate intraslab raypaths and determine the spatial distribution of anisotropy within the Nazca slab. We observe that in the upper mantle, the intraslab anisotropy appears strongest where the slab is most contorted, suggesting a strong link between anisotropy and subduction-related slab deformation. We identify a second source of anisotropy (δt∼ 1 s) within the subducting slab at lower mantle depths (660–800 km). The surrounding mantle and transition zone appear largely isotropic, with deep anisotropy concentrated within the slab as it deforms while entering the higher-viscosity lower mantle.",
keywords = "Nazca slab, seismic anisotropy, slab anisotropy, slab deformation, source side splitting",
author = "Shubham Agrawal and Eakin, {Caroline M.} and Portner, {Daniel E.} and Rodriguez, {Emily E.} and Beck, {Susan L.}",
note = "Funding Information: We thank three anonymous reviewers for their constructive comments. All seismic data used in this study were acquired from IRIS ( https://www.iris.edu ) Data Management Center. Full details of all 11 networks, including a list of DOIs, are provided in the supporting information (Text S1 ). We used the SplitLab 1.2.1 (W{\"u}stefeld et al., 2008 ) updated by Rob Porritt ( https://robporritt.wordpress.com/software/ ). S. A. and C. M. E. are currently supported by Australian Research Council Grant DE190100062. A table of all measurements made during this study can be found in the supporting information (Tables S5 and S6 ). Funding Information: We thank three anonymous reviewers for their constructive comments. All seismic data used in this study were acquired from IRIS (https://www.iris.edu) Data Management Center. Full details of all 11 networks, including a list of DOIs, are provided in the supporting information (Text S1). We used the SplitLab 1.2.1 (W{\"u}stefeld et al., 2008) updated by Rob Porritt (https://robporritt.wordpress.com/software/). S. A. and C. M. E. are currently supported by Australian Research Council Grant DE190100062. A table of all measurements made during this study can be found in the supporting information (Tables S5 and S6). Publisher Copyright: {\textcopyright}2020. American Geophysical Union. All Rights Reserved.",
year = "2020",
month = jun,
day = "16",
doi = "10.1029/2020GL087398",
language = "English (US)",
volume = "47",
journal = "Geophysical Research Letters",
issn = "0094-8276",
publisher = "American Geophysical Union",
number = "11",
}