Neodymium isotope equilibration during crustal metamorphism revealed by in situ microanalysis of REE-rich accessory minerals
作者: J. HammerliA.I.S. KempC. Spandler
作者单位: 1School of Earth and Environmental Sciences, James Cook University, Townsville, Australia
2Centre for Exploration Targeting, University of Western Australia, Perth, Australia
刊名: Earth and Planetary Science Letters, 2014, Vol.392 , pp.133-142
来源数据库: Elsevier Journal
DOI: 10.1016/j.epsl.2014.02.018
关键词: Nd isotope equilibrationlaser ablation MC-ICP-MSaccessory mineralsanatexis
原始语种摘要: Abstract(#br)Radiogenic isotopes are widely used to investigate crustal evolutionary processes, however recent claims of Nd and Sr isotope disequilibrium during anatexis question the reliability of such information. We have conducted an in situ Sm–Nd isotope study of apatite, allanite, titanite, xenotime and monazite in metasedimentary rocks of different metamorphic grade to test Nd isotope equilibrium during metamorphism. Our results show that apatite retains an original, probably detrital, highly variable Nd isotopic signature until at least 500 °C before being isotopically homogenised, irrespective of textural context within the rock. Once equilibrated, apatite retains its Nd isotope signature throughout anatexis. In contrast, allanite and titanite are equilibrated at temperatures as...
全文获取路径: Elsevier  (合作)
影响因子:4.349 (2012)