华北克拉通北缘元古宙大庙Fe-Ti-P矿床的挥发份组成和C-H-O同位素研究.pdfVIP

1000-0569／2011／027(05)一1500—10 ActaPetrologicaSinica 岩石学报 华北克拉通北缘元古宙大庙 Fe．Ti．P矿床 的挥发份 组成和 C-H．o同位素研究 邢长明1,2 陈伟 王焰 赵太平 XINGChangMing，-．CHENWei．WANGChristinaYan andZHA0TaiPing 1．中国科学院广州地球化学研究所，中国科学院矿物学与成矿学重点实验室，广州 510640 2．中国科学院研究生院，北京 100049 3．香港大学地球科学系，香港 1．KeyLaboratoryofMineralogyandMetallogeny，GuangzhouInstituteofGeochemistry，ChineseAcademyofSciences，Guangzhou510640，China 2．GraduateUniversityofChineseAcademyofSciences，Bejiing10004-9，China 3．DepartmentofEarthSciences，theUniversityofl-longKong，HongKong，China 2010．12．12收稿 ．2011-03—18改 回． XingCM ，ChenW ，W angCY andZhaoTP．2011．Volatilecomponentsand C-H-O isotopiccompositionsofProterozoic DamiaoFe-Ti—PoxidedepositinthenorthernmarginoftheNorthChinaCraton．ActaPetrologicaSinica，27(5)：1500—1510 Abstract The ～1．74GaDamiaomassif-typeanorthositecomplexinthenoahernmarginoftheNoAhChinaCratonhostsalargeFe- Ti—Poxidedeposit．Volatilesthatweretrappedinmagnetite．apatiteandplagioclaseofmassiveFe—Tiore．massiveFe—Ti—Poreand disseminatedoreweremeasuredbystepheatingmassspectrometeratthreereleasingtemperatureintervals200～400~C ．400—800℃ and800～1200~C toobtainmajorcomponentsandC—H—Oisotopiccomposition．Fourtypesoffluidwereidentifiedfromthevolatiles： (1)metamorphicfluidreleasedrfomplagioclaseat800～1200~Ctemperatureinterval，mainlycomposedofH2O，N2+COandCO2； (2)mantle—derivedfluidreleasedfromplagioclaseat400～800％temperatureinterval，mainlycomposedofH2，H2O，CH4andCO2； (3)sul~acewaterreleasedfrommagnetiteat400～800~Ctemperatureinterval，mainlycomposedofH2O，CO2，SO2andH2s；nad (4)secondaryfluidreleasedfrommineralsat200—400℃ temperatureinterval，mainlycomposedofH2OandCO2．Magnetiteinboth massiveFe．TioreandmassiveFe．Ti—P orecontainshighcontentsofH，0 andCO，，indicatingarelativelyoxidizedconditiondueto concentrationofearly．formed fluids and surface water at late stage ofmagma fraetionation sequence，whereasplagioelase in disseminatedorecontainsabundantH2andCH4，indicatingarelativereduced．Itisproposedthat