Intermittent generation of mafic enclaves in the 1991–1995 dacite of Unzen Volcano recorded in mineral chemistry
作者: Hiroaki SatoFrancois HoltzRoman E. BotcharnikovSetsuya Nakada
作者单位: 1Kobe University
2Institute of Mineralogy
3The University of Tokyo
刊名: Contributions to Mineralogy and Petrology, 2017, Vol.172 (4)
来源数据库: Springer Nature Journal
DOI: 10.1007/s00410-017-1335-3
关键词: Mafic enclavesMg in plagioclaseCl in hornblendeMagma mixingDiffusion re-equilibrationUnzen volcano
原始语种摘要: Mafic enclaves in the 1991–1995 dacite of Unzen volcano show chemical and textural variability, such as bulk SiO2 contents ranging from 52 to 62 wt% and fine- to coarse-grained microlite textures. In this paper, we investigated the mineral chemistry of plagioclase and hornblende microlites and distinguished three enclave types. Type-I mafic enclaves contain high-Mg plagioclase and low-Cl hornblende as microlites, whereas type-III enclaves include low-Mg plagioclase and high-Cl hornblende. Type-II enclaves have an intermediate mineral chemistry. Type-I mafic enclaves tend to show a finer-grained matrix, have slightly higher bulk rock SiO2 contents (56–60 wt%) when compared with the type-III mafic enclaves (SiO2 = 53–59 wt%), but the overall bulk enclave...
全文获取路径: Springer Nature  (合作)
影响因子:3.476 (2012)

  • mafic 镁铁质的
  • dacite 英安岩
  • plagioclase 斜长石
  • hornblende 角闪石
  • magma 岩浆
  • mineral 矿物
  • reservoir 贮水池
  • microlite 微晶石
  • rhyolitic 流纹岩的
  • temperature 温度