摘要
Forthefirsttime,wepresenttherareearthelement(REE)andsulfurisotopiccompositionofhydrothermalprecipitatesrecoveredfromtheTangyinhydrothermalfield(THF),OkinawaTroughatawaterdepthof1206m.Thenaturalsulfursamplesexhibitthelowest∑REEconcentrations(∑REE=0.65×10^-6-4.580×10^-6)followedbymetalsulfides(∑REE=1.71×10^-6-11.63×10^-6).Bycontrast,thenaturalsulfur-sedimentsampleshavemaximum∑REEconcentrations(∑REE=11.54×10^-6-33.06×10^-6),significantlylowerthanthoseofthevolcanicandsedimentsamples.Nevertheless,theδEu,δCe,(La/Yb)N,La/Sm,(Gd/Yb)Nandnormalizedpatternsofthenaturalsulfurandmetalsulfideshowthemostsimilaritytothesediment.MosthydrothermalprecipitatesamplesarecharacterizedbyenrichmentsofLREE(LREE/HREE=10.09-24.53)aridslightlynegativeEuanomaliesornoanomaly(δEu=0.48-0.99),whicharedifferentfromthehydrothermalfluidfromsediment-freemid-oceanicridgesandback-arebasins,butidenticaltothesulfidesfromtheJadehydrothermalfield.Thelowertemperatureandmoreoxidizingconditionsproducedbythemixingbetweenseawaterandhydrothermalfluidsfurtherattenuatetheleachingabilityofhydrothermalfluid,inducinglowerREEconcentrationsfornaturalsulfurcomparedwithmetalsulfide;meanwhile,thenegativeEuanomalyisalsoweakenedoralmostabsent.Thesulfurisotopiccompositionsofthenaturalsulfur(δ^34S=3.20‰-5.01‰,mean4.23‰)andmetalsulfidesamples(δ34S=0.82‰-0.89‰,mean0.85‰)revealthatthesulfurofthechimneyissourcedfrommagmaticdegassing.
出版日期
2018年02月12日（中国期刊网平台首次上网日期，不代表论文的发表时间）
