Re-Os dating of the Makimine and Shimokawa VMS deposits for new age constraints on ridge subduction beneath Japanese Islands.

ABSTRACT: Ridge subduction is a trigger of thermal metamorphism and hydrothermal activity; thus, it is an important process for understanding geological history of accretionary complexes. However, determining the timing of ridge subduction is often challenging owing to metamorphism and poor microfossil preservation. Some Besshi-type volcanogenic massive sulphide (VMS) deposits associated with in situ greenstone originated by hydrothermal mineralisation on a sediment-covered mid-ocean ridge (MOR); thus, their depositional ages constrain the timing of ridge subduction. Here, we report Re-Os isochron ages of the Makimine and Shimokawa VMS deposits in southwest and northeast Japan. The Re-Os isotope ratios exhibit well-defined linearity and their isochron ages are 89.4 ± 1.2 and 48.2 ± 0.9 Ma. Consideri

SUBMITTER: Nozaki T 

PROVIDER: S-EPMC11615321 | biostudies-literature | 2024 Dec

REPOSITORIES: biostudies-literature