Diversities of chromite mineralization induced by chemo-thermal evolution of the mantle during subduction initiation.

ABSTRACT: Ophiolites, mostly formed via subduction initiation at proto-forearcs, exhibit a unique variation of mantle-derived magmatism from MORB-like to low-Ti tholeiitic and bainitic-like affinities. Such variation was suggested to form chromite deposits spanning high-Al to high-Cr types. Nevertheless, the origin of diverse magmatism during subduction initiation and their linkages to different chromite deposits has long been enigmatic. Here we show elemental and Os isotopic compositions of different chromitites from the Zambales ophiolite, Philippines. Combined with data from ophiolites worldwide, high-Al and high-Cr chromitites are revealed to result from low-Ti tholeiitic and boninitic-like magmatism, respectively. Proto-forearc mantle had few chromitites generated during MORB-like magmatism, bu

SUBMITTER: Zhang PF 

PROVIDER: S-EPMC11525652 | biostudies-literature | 2024 Oct

REPOSITORIES: biostudies-literature