Platinum-group elements and rhenium in mantle xenoliths from the East Sayan volcanic field (Siberia, Russia): evaluation of melt extraction and refertilization processes in lithospheric mantle of the Tuva-Mongolian massif
2008; Wiley; Volume: 20; Issue: 6 Linguagem: Inglês
10.1111/j.1365-3121.2008.00851.x
ISSN1365-3121
AutoresА. В. Иванов, С. В. Палесский, Е. I. Demonterova, И. В. Николаева, Igor Ashchepkov, С. В. Рассказов,
Tópico(s)Geochemistry and Geologic Mapping
ResumoAbstract We determined the concentrations of platinum‐group elements (PGE) and rhenium in granular spinel lherzolites entrained as xenoliths in the Late Cenozoic volcanic rocks of the East Sayan within the Sarkhoi palaeo‐arc block of the Tuva‐Mongolian massif. Major element, PGE and rhenium variations in the East Sayan xenoliths can be explained by impregnation of up to 15% of arc‐type melt into initially depleted mantle harzburgite. Such a refertilization process probably took place in the Middle Neoproterozoic, when the Tuva‐Mongolian massif was in a subduction environment. East Sayan xenoliths show close similarities to Vitim xenoliths, whose host basalts erupted within an off‐cratonic crustal block. Both East Sayan and Vitim xenoliths are different from cratonic and circum‐cratonic peridotite xenoliths of worldwide localities.
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