Primary carbonatite melt from deeply subducted oceanic crust
نویسندگان
چکیده
منابع مشابه
Geochemical heterogeneity and element mobility in deeply subducted oceanic crust; insights from high-pressure mafic rocks from New Caledonia
Bulk-rock major and trace element geochemistry of a range of eclogite, garnet blueschist and garnet amphibolite rocks from northern New Caledonia has been determined in order to geochemically characterise subducted oceanic crust. The rocks experienced peak metamorphic conditions of 1.9 GPa and 600 jC and represent excellent samples of oceanic crust that was subducted to depths of approximately ...
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The deep marine biosphere has over the past decades been exposed as an immense habitat for microorganisms with wide-reaching implications for our understanding of life on Earth. Recent advances in knowledge concerning this biosphere have been achieved mainly through extensive microbial and geochemical studies of deep marine sediments. However, the oceanic crust buried beneath the sediments, is ...
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We present a melt percolation model incorporating finite solid diffusion to provide a quantitative constraint on how melt migrates through the oceanic lower crust at fast-spreading ridge axes. The lower crustal, layered gabbro in the Oman ophiolite, which was formed at a fast-spreading ridge, shows correlated variations in primary mineral compositions with a vertical wavelength less than 100–20...
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ژورنال
عنوان ژورنال: Nature
سال: 2008
ISSN: 0028-0836,1476-4687
DOI: 10.1038/nature07132