Noble gases in submarine pillow volcanic glasses

摘要: Abstract Fifteen submarine glasses from the East Pacific Rise (CYAMEX), Kyushu-Palau Ridge (DSDP Leg 59) and Nauru Basin 61) were analysed for noble gas contents isotopic ratios. Both samples showed Ne excess relative to Ar a monotonic decrease Xe when compared with air abundance. This characteristic abundance pattern (type 2, classified by Ozima Alexander) is interpreted be due two-stage degassing reservoir originally atmospheric In sample, gases are nearly ten times more abundant than in samples. may attributed an oceanic crust contamination former mantle source. There no correlation between He content that of other CYAMEX suggests was derived larger region, independent gases. Except where radiogenic isotopes involved, all ratios indistinguishable The3He/4He shows remarkably uniform ratio (1.21±0.07)×10−5, while the40Ar/36Ar ranges 700 5600.