Skip to Main content Skip to Navigation
Journal articles

Decreasing magnetization, lithospheric flexure and rejuvenated hydrothermalism off the Japan-Kuril subduction zone

Abstract : Seafloor spreading magnetic anomalies formed at mid‐ocean ridges initially display strong amplitudes that decay within the first 10 million years as a result of pervasive hydrothermal circulation and alteration. The amplitudes do not vary much for older oceanic crust, suggesting that the thickening sediments hinder heat advection. Here we show, however, that a systematic loss of ~20 % in the amplitude of the anomalies arises between the outer rise and the trench on old ocean crust approaching the Japan and Kuril subduction zones. We interpret this decay as reflecting the opening of normal faults and fissures caused by extension on the outer flexural rise, and the subsequent renewed circulation of seawater into the oceanic crust, resulting in additional alteration of the magnetic minerals. This interpretation is supported by higher heat flow and seismic velocity changes observed toward the trench
Document type :
Journal articles
Complete list of metadatas

Cited literature [33 references]  Display  Hide  Download

https://hal-insu.archives-ouvertes.fr/insu-02520688
Contributor : Eva Fareau <>
Submitted on : Wednesday, May 27, 2020 - 4:33:48 PM
Last modification on : Friday, June 12, 2020 - 5:38:03 PM

File

2019GL085975.pdf
Publisher files allowed on an open archive

Identifiers

Collections

Citation

Hanjin Choe, Jerôme Dyment. Decreasing magnetization, lithospheric flexure and rejuvenated hydrothermalism off the Japan-Kuril subduction zone. Geophysical Research Letters, American Geophysical Union, 2020, 47 (9), pp.e2019GL085975. ⟨10.1029/2019GL085975⟩. ⟨insu-02520688⟩

Share

Metrics

Record views

289

Files downloads

16