期刊文献+

大别地体新店榴辉岩变质锆石U-Pb年龄和氧同位素研究 被引量:13

原文传递
导出
摘要 对大别山南部新店超高压榴辉岩两件锆石样品进行了详细的阴极发光、微区U-Pb年龄和氧同位素研究,发现存在两类锆石.一类为短粗、等轴状锆石,量大,是原岩岩浆锆石,并遭受了一定程度的重结晶,形成时间在811±22Ma.另一类为自形、棱柱状锆石,量少,有核-边结构,边部是超高压变质时期形成的变质增生锆石,变质作用发生在221~217Ma.所有原岩岩浆锆石的Th/U比均在1.3左右,随变质重结晶程度增加,Th/U比下降,变质增生锆石Th/U比均低于0.1.锆石阴极发光强度主要由U和Th含量控制.无论是岩浆锆石还是变质锆石的δ^(18)O值都很低,平均值分别为1.8‰和2.8‰.原岩锆石的低δ^(18)O值表明其形成时源区有显著的大气降水加入,这可能和全球范围内晚前寒武纪雪球地球事件有关,也表明在大别山变质环境下,榴辉岩相变质作用不能使原岩锆石氧同位素发生明显再造.
出处 《中国科学(D辑)》 CSCD 北大核心 2005年第8期691-699,共9页 Science in China(Series D)
基金 国家自然科学基金(批准号:40273028) 科学技术部基础研究项目(批准号:G1999075503)资助项目
  • 相关文献

参考文献36

  • 1Vavra G, Gebauer D, Schmid R, et al. Multiple zircon growth and recrystallization during polyphase Late Carboniferous to Triassic metamorphism in granulites of the Ivrea Zone (Southern Alps): an ion microprobe (SHRIMP) study. Contrib Mineral Petrol, 1996,122:337-358.
  • 2Vavra G, Schmid R, Gebauer D. Internal morphology, habit and U-Th-Pb microanalysis of amphibolite to granulite facies zircons:geochronology of the Ivrea Zone (Southern Alps). Contrib Mineral Petrol, 1999, 134:380,-404.
  • 3Rubatto D, Gebauer G, Compagnoni R. Dating of eclogite-facies zircons: the age of Alpine metamorphism in the Sesia-Lanzo Zone(Western Alps). Earth and Planetary Science Letters, 1999, 167:141-158.
  • 4Valley J W, Chiarenelli J R, McLelland J M. Oxygen isotope geochemistry of zircon. Earth Planet Sci Lett, 1994, V126:187-206.
  • 5King E M, Barrie C T, Valley J W. Hydrothermal alteration of oxygen isotope ratios in quartz phenocrysts, Kidd Creek mine,Ontario: magmatic values are preserved in zircon. Geology, 1997,V23:1079-10826.
  • 6Liou J G, Zhang R Y, Wang X, et al. Metamorphism and tectonics of high-pressure and ultrahigh-pressure belts in the Dahie-Sulu region, China. In: Yin A. Harrison M. eds. The Tectonic Evolution of Asia. New York: Cambridge University Press, 1996. 330-344.
  • 7Xu S, Okay A I, Ji S, et al. Diamond from Dabie Shan metamorphic rocks and its implications for tectonic setting. Science, 1992,256:80-,-92.
  • 8Okay A I. Petrology of diamond and coesite-bearing metamorphic terrane, Dabie Shan, China. Eur J Mineral, 5:659,4576.
  • 9Wang X, Liou J G, Maruyama S. Coesite-bearing eclogite from the Dabie Mountains, Central China: petrogenesis, P-T paths and implications for regional tectonics. J Geol, 1992, 100:231-250.
  • 10Carswell D A, Wilson R N, Zhai M. Metamorphic evolution, mineral chemistry and thermobarometry of schists and orthogneisses hosting ultra-high pressure eclogites in the Dabieshan of central China. Lithos, 2000, 52:121-155.

二级参考文献8

共引文献114

同被引文献405

引证文献13

二级引证文献191

相关作者

内容加载中请稍等...

相关机构

内容加载中请稍等...

相关主题

内容加载中请稍等...

浏览历史

内容加载中请稍等...
;
使用帮助 返回顶部