地球岩石的化学组成

地球岩石的化学组成作者：卡卡西地球中微子⟷地球科学问题

CompositionoftheBulkSilicateEarth(BSE)CompositionoftheEarth’smantleCompositionoftheEarth’scrustUThK

岩石密度元素丰度结构信息U和Th元素在地球中的总量和分布CompositionoftheBSEchondrite（球粒陨石）CosmochemistrymodelCompositionoftheBSEGeochemistrymodelCompositionoftheBSEGeochemistrymodelCompositionoftheBSEGeochemistrymodelTheKconcentrationintheEarthisprobablyonlycertaintoaboutafactoroftwo.CompositionoftheBSE?ThematterfromwhichtheEarthformedwasNOTchondritic;OrtheEarthhaslostmatterbycollisionalerosion.Massbalancerequiresthatamissingreservoir,whichwouldhosttheequivalentofthemoderncontinents’budgetofradioactiveheat-producingelements(U,ThandK),

yethasnotbeendiscovered.Wearguethatthisreservoircouldhavebeenlosttospace.CompositionoftheEarth’smantleUppermantle,MORBperidotite（橄榄岩）Lower

mantle,OIBbasalt（玄武岩）CompositionoftheEarth’smantleCi=CM*[F+D*(1-F)]-1Ci=CM*F/[1-(1-F)1/D]DepletedMantleEnrichedMantle(Srameketal.,2013)

HeterogeneouscompositionoftheEarth’smantle(Huang&Zhao,2006)

EnrichedMantle?CompositionoftheEarth’scrustOceaniccrust:Sediment（沉积物）Basalt（玄武岩）Gabbro（辉长岩）Continentalcrust:ComplexCompositionoftheEarth’scrustContinentalcrust

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uppercrustJUNO岩浆岩和变质岩高SiO2=高U,Th(Gaoetal.,2020)

CompositionoftheEarth’scrustContinentalcrust

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lowercrustMetamorphicterranes（地体）Xenoliths（捕掳体）挤压环境相对高SiO2拉张环境相对低SiO2U(ppm)(Huangetal.,2013)

CompositionoftheEarth’scrustHowtoformthecompositionoftheEarth’scrust?低SiO2熔体高SiO2陆壳高SiO2,U,Th低SiO2,U,Th拆沉模型风化模型高SiO2岩石更抗风化(Lietal.,2016)

CompositionoftheBulkSilicateEarth(BSE)HeterogeneouscompositionoftheEarth’smantleHowtoformthecompositionoftheEarth’scrustConclusionsUThK

Thankyou!18华南的岩浆岩具有更高