Boron isotopic signatures of melt inclusions from North Iceland reveal recycled material in the Icelandic mantle source ...

• Main Authors: Shorttle, Oliver, Hartley, Margaret, De Hoog, Cees-Jan
• Format: Article in Journal/Newspaper
• Language: English
• Published: Meteoritical Society 2021
• Subjects: Reykjanes; Iceland
• Online Access: https://dx.doi.org/10.17863/cam.60061; https://www.repository.cam.ac.uk/handle/1810/312961

Trace element and volatile heterogeneity in the Earth's mantle is in uenced by the recycling of oceanic lithosphere through subduction. Oceanic island basalts commonly have high concentrations of volatiles compared to mid-ocean ridge basalts, but the extent to which this enrichment is linked to recycled mantle domains remains unclear. Boron is an ideal tracer of recycled subducted material, since only a small percentage of a recycled component is required to modify the bulk X11B of the source mantle. Boron isotopic compositions of primary melts thus have potential to trace the fate of recycled subducted material in the deep mantle, and to constrain the lengthscales of lithologic and compositional heterogeneities in diverse tectonic settings. We present new measurements of volatiles, light elements and boron isotopic ratios in basaltic glasses and melt inclusions that sample the mantle at two endmember spatial scales. Submarine glasses from the Reykjanes Ridge sample long-wavelength mantle heterogeneity on ...