Abstract
Subducted sediments are thought to lubricate the subduction interface and promote faster plate speeds. However, global observations are not clear-cut on the relationship between the amount of sediments and plate motion. Sediments are also thought to influence slab dip, but variations in subduction geometry depend on multiple factors. Here we use 2D thermomechanical models to explore how sediments can influence subduction dynamics and geometry. We find that thick sediments can lead to slower subduction due to an increase of the megathrust shear stress as the accretionary wedge gets wider, and a decrease in slab pull as buoyant sediments are subducted. Our results also show that larger slab buoyancy and megathrust stress due to thick sediments increase the slab bending radius. This offers a new perspective on the role of sediments, suggesting that sediment buoyancy and wedge geometry also play an important role on large-scale subduction dynamics.
| Original language | English |
|---|---|
| Article number | e2021GL096266 |
| Pages (from-to) | 1-12 |
| Journal | Geophysical Research Letters |
| Volume | 48 |
| Issue number | 20 |
| DOIs | |
| Publication status | Published - 28 Oct 2021 |
Bibliographical note
Funding Information:T. W. Becker was partially supported by EAR‐1925939 and EAR‐1853856. W. M. Behr was partially supported by European Research Council (ERC) Starting Grant S‐SIM (947659). I. van Zelst was funded by the Royal Society (UK) through Research Fellows Enhancement Award RGF\EA\181084. L. Dal Zilio was supported by the Swiss National Science Foundation (SNSF) (grant P400P2_199295). The authors thank two anonymous reviewers, A. Pusok and F. Funiciello for constructive comments that helped to improve the quality of this manuscript.
Publisher Copyright:
© 2021. American Geophysical Union. All Rights Reserved.
Funding
T. W. Becker was partially supported by EAR‐1925939 and EAR‐1853856. W. M. Behr was partially supported by European Research Council (ERC) Starting Grant S‐SIM (947659). I. van Zelst was funded by the Royal Society (UK) through Research Fellows Enhancement Award RGF\EA\181084. L. Dal Zilio was supported by the Swiss National Science Foundation (SNSF) (grant P400P2_199295). The authors thank two anonymous reviewers, A. Pusok and F. Funiciello for constructive comments that helped to improve the quality of this manuscript.