Flare-up in Cordilleran arcs controlled by fluxes in subduction water budgets

Chapman, Timothy; Milan, Luke A; Zahirovic, Sabin; Merdith, Andrew S; Clarke, Geoffrey L; Sun, Mingdao; Daczko, Nathan R

doi:10.1016/j.tecto.2024.230457

Author(s)

Chapman, Timothy

Milan, Luke A

Zahirovic, Sabin

Merdith, Andrew S

Clarke, Geoffrey L

Sun, Mingdao

Daczko, Nathan R

Publication Date

2024-10-08

Abstract

The tempo of subduction-related magmatic activity over geological time is episodic. Despite intense study and its importance to crustal growth, the fundamental drivers of this episodicity remains unclear. We demonstrate quantitatively a first order relationship between arc flare-up events and high subduction flux. The volume of oceanic lithosphere entering the mantle is the key parameter that regulates the proportion and rate of H2O entering the sub-arc. New estimates of subduction zone H2O flux over the last 150 million-years indicate a three-to five-fold increase in the proportion of H2O entering the sub-arc during the most recent global pulse of magmatism. Step changes in H2O flux enable proportionally greater partial melting in the sub-arc mantle leading to a flare-up episode. Similar magmatic flare-ups in the ancient Earth could be related to variability in slab flux associated with supercontinent cycles.

Citation

Tectonophysics, v.888, p. 1-11

ISSN

1879-3266

0040-1951

Link

https://hdl.handle.net/1959.11/62549

Language

en

Publisher

Elsevier BV

Title

Flare-up in Cordilleran arcs controlled by fluxes in subduction water budgets

Type of document

Journal Article

Entity Type

Publication

Author(s)	Chapman, Timothy Milan, Luke A Zahirovic, Sabin Merdith, Andrew S Clarke, Geoffrey L Sun, Mingdao Daczko, Nathan R
Publication Date	2024-10-08
Abstract	<p>The tempo of subduction-related magmatic activity over geological time is episodic. Despite intense study and its importance to crustal growth, the fundamental drivers of this episodicity remains unclear. We demonstrate quantitatively a first order relationship between arc flare-up events and high subduction flux. The volume of oceanic lithosphere entering the mantle is the key parameter that regulates the proportion and rate of H<sub>2</sub>O entering the sub-arc. New estimates of subduction zone H<sub>2</sub>O flux over the last 150 million-years indicate a three-to five-fold increase in the proportion of H<sub>2</sub>O entering the sub-arc during the most recent global pulse of magmatism. Step changes in H<sub>2</sub>O flux enable proportionally greater partial melting in the sub-arc mantle leading to a flare-up episode. Similar magmatic flare-ups in the ancient Earth could be related to variability in slab flux associated with supercontinent cycles.</p>
Citation	Tectonophysics, v.888, p. 1-11
ISSN	1879-3266 0040-1951
Link	https://hdl.handle.net/1959.11/62549
Language	en
Publisher	Elsevier BV
Title	Flare-up in Cordilleran arcs controlled by fluxes in subduction water budgets
Type of document	Journal Article
Entity Type	Publication

Flare-up in Cordilleran arcs controlled by fluxes in subduction water budgets

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