CaltechAUTHORS
  A Caltech Library Service

A long-lived Indian Ocean slab: Deep dip reversal induced by the African LLSVP

Wang, Huilin and Wang, Yaoyi and Gurnis, Michael and Zahirovic, Sabin and Leng, Wei (2018) A long-lived Indian Ocean slab: Deep dip reversal induced by the African LLSVP. Earth and Planetary Science Letters, 497 . pp. 1-11. ISSN 0012-821X. http://resolver.caltech.edu/CaltechAUTHORS:20180615-091644667

[img] MS Word (We use 2D (part 1) and global (part 2) models to investigate the dynamics of a sinking slab in deep mantle. The following materials provide the detailed model setup (Tables S1 and S2) and modeling results (Figs. S2–S4)) - Supplemental Material
See Usage Policy.

1321Kb

Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20180615-091644667

Abstract

A slab-like high seismic velocity anomaly (referred as SEIS) has been inferred beneath the central-southern Indian Ocean in a recent tomographic inversion. Although subduction has previously been suggested regionally by surface observations, the new inversion is consistent with a north-dipping slab extending from the upper mantle to the core mantle boundary (CMB). We propose that SEIS anomaly originated from an oceanic plate in the Paleo-Tethys that was consumed by a south-dipping intra-oceanic subduction zone during the Triassic and Jurassic periods. SEIS challenges traditional concepts of the dynamics of slab descent by its relatively shallow depths and a present-day polarity opposite to the geometry of subduction. Geodynamic models show the upwelling mantle flow exerted by a thermochemical pile can hold and stagnate the descending SEIS slab at shallow depths for more than 100 Myr. The spatial distribution of resistance from the upwelling mantle flow can reverse the slab dip, producing a structure consistent with seismic inversions as well as with our proposed tectonic scenario and geology constraining the Tethyan tectonic domain. The results suggest that slabs can descend through the lower mantle at rates substantially lower than 1 cm/yr, and even reverse their polarity through interactions with background mantle flow.


Item Type:Article
Related URLs:
URLURL TypeDescription
https://doi.org/10.1016/j.epsl.2018.05.050DOIArticle
ORCID:
AuthorORCID
Wang, Huilin0000-0003-3061-0806
Gurnis, Michael0000-0003-1704-597X
Additional Information:© 2018 Elsevier B.V. Received 31 October 2017, Revised 28 May 2018, Accepted 30 May 2018, Available online 15 June 2018. We thank two anonymous reviewers for their invaluable comments and suggestions. We also thank Nathan Simmons for earlier discussions on the origin of the SEIS and Kara Matthews for discussions of Tethyan reconstructions. HW and MG were supported by the National Science Foundation through EAR-1600956 and EAR-1645775 and by Statoil ASA. YW participated through the Visiting Undergraduate Research Program (VURP) at Caltech. SZ was supported by the Australian Research Council through IH130200012. The original CitcomS code is obtained from Computational Infrastructure for Geodynamics (http://geodynamics.org).
Group:Seismological Laboratory
Funders:
Funding AgencyGrant Number
NSFEAR-1600956
NSFEAR-1645775
Statoil ASAUNSPECIFIED
Australian Research CouncilIH130200012
Subject Keywords:mantle convection; subducted slab dynamics; LLSVPs; upwelling mantle flow; slab morphology
Record Number:CaltechAUTHORS:20180615-091644667
Persistent URL:http://resolver.caltech.edu/CaltechAUTHORS:20180615-091644667
Official Citation:Huilin Wang, Yaoyi Wang, Michael Gurnis, Sabin Zahirovic, Wei Leng, A long-lived Indian Ocean slab: Deep dip reversal induced by the African LLSVP, Earth and Planetary Science Letters, Volume 497, 1 September 2018, Pages 1-11, ISSN 0012-821X, https://doi.org/10.1016/j.epsl.2018.05.050. (https://www.sciencedirect.com/science/article/pii/S0012821X18303339)
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:87148
Collection:CaltechAUTHORS
Deposited By: Tony Diaz
Deposited On:15 Jun 2018 18:30
Last Modified:15 Jun 2018 18:30

Repository Staff Only: item control page