The Role of Continental Heterogeneity on the Evolution of Continental Margin Topography at Subduction Zones

This is a Preprint and has not been peer reviewed. The published version of this Preprint is available: https://doi.org/10.1016/j.epsl.2024.118856. This is version 2 of this Preprint.

Add a Comment

You must log in to post a comment.


Comments

There are no comments or no comments have been made public for this article.

Downloads

Download Preprint

Authors

Antoniette Greta Grima, Thorsten W. Becker 

Abstract

The nature of the overriding plate plays a major role in shaping subduction zone processes. In particular, the highly heterogeneous continental lithosphere modulates intra-plate tectonics and the surface evolution of our planet. However, the role of continental heterogeneity is relatively under-explored for the dynamics of subduction models. We investigate the influence of rheological and density variations across the overriding plate on the evolution of continental lithosphere and slab dynamics in the upper mantle. We focus on the effects of variations in continental margin and keel properties on deformation, topographic signals, and basin formation. Our results show that the thickness, extent, and strength of the continental margin and subcontinental keel play a crucial role for the morphology and topography of the overriding plate, as well as the retreat of the subducting slab. We show that this lateral heterogeneity can directly influence the coupling between the subducting and overriding plate and determine the partitioning of plate velocities across the overriding plate. These findings suggest that back-arc extension and subsidence are not solely controlled by slab dynamics but are also influenced by continental margin and keel properties. Large extended back-arc regions, such as the Pannonian and Aegean basins, may result from fast slab rollback combined with a weak continental margin and a strong and extended continental keel. Narrow margins, like the Okinawa Trough in NE Japan, may indicate a comparatively stronger continental margin and weaker or smaller continental keel. Additionally, continental keel properties may affect the overall topography of the continental lithosphere, leading to uplift of the deformation front and the formation of intermontane basins.

DOI

https://doi.org/10.31223/X5N671

Subjects

Earth Sciences, Geophysics and Seismology, Other Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure

Keywords

Continental margin topography, Continental heterogeneity, Back-arc extension, Subduction zone evolution

Dates

Published: 2023-09-01 21:38

Last Updated: 2024-07-09 22:02

Older Versions
License

CC BY Attribution 4.0 International

Additional Metadata

Conflict of interest statement:
None

Data Availability (Reason not available):
Available upon reasonable request