Publication Date:
2011-07-01
Description:
Serpentinite mud volcanoes from the Mariana forearc comprise B-rich mantle wedge peridotites serpentinized by slab fluids. The major component of these rocks are serpentine group minerals [Mg3Si2O5(OH)4], showing highly variable textural and geochemical features. Micro-Raman spectroscopy reveals that the serpentine minerals are well-crystallized lizardite and chrysotile. In situ SIMS spot analyses and element mapping via ToF-SIMS show that B is evenly distributed across serpentine grains, suggesting that serpentine, both lizardite and chrysotile in different textural regions, can host significant amounts of B (up to ~200 {micro}g/g) into its crystal structure. As such structurally bound B can only be released during recrystallization or serpentine breakdown, our results have implications for modeling of the efficiency of cross-arc fluid mobile element recycling in subduction zones and stress the importance of the hydrated forearc mantle as a reservoir for fluid mobile elements.
Print ISSN:
0003-004X
Electronic ISSN:
1945-3027
Topics:
Geosciences
