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| Titel |
LA-(HR-)ICPMS study of serpentinites from ODP Site 920 (23°N MAR): insights on transfers and trace element distribution during serpentinization |
| VerfasserIn |
M. Andréani, M. Godard, C. Mével |
| Konferenz |
EGU General Assembly 2009
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250030907
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| Zusammenfassung |
| The numerous ultramafic-hosted hydrothermal systems discovered during the last ten years emphasized the importance of mantle peridotite alteration as means of chemical exchange between the mantle and the ocean at slow- and ultra-slow spreading ridges. Yet, little is known on the chemical variability of serpentinites at the ridge and the local scale. This is determinant for constraining mass transfers at ridge axis and then the input budget in subduction zones.
We present the results of the detailed petrostructural and geochemical study of serpentinized harzburgites (60-100 % alteration) sampled at ODP Site 920 (23°N, Mid-Atlantic Ridge). A previous detailed microstructural and major element study of pseudomorphic textures and veins of site 920 serpentinites has indicated two main stages of serpentinization which accompany the progressive unroofing of mantle rocks. These stages are distinguished by their mode of mass transfer: a first diffusion-dominated stage occurring below 2 km in depth at 150°
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