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  • 館藏編號:NTUG010-T700089
  • 題名:岩石地球化學及地球的演化
  • 作者:孫賢鉥
  • 藏品形式:稿本
  • 尺寸:297X210(mm)
  • 簡述:第六講 島弧玄武岩, 板塊隱沒及大陸地殼的形成
  • 內容:

    Fig 2. Through-time variation of Sr and Nd isotopic compositions of volcanic rocks along the volcanic front in the NE Japan arc (open circles = Tertiary volcanics; solid circles=Quaternay volanics). The isotopic compositions of magmas source regions have been quite constant for trench side volcanics compared with back-arc side volacnics (hatched areas).
    Fig 3. The along-arc variation of Sr isotope rations in volcanic rocks from the NE Japan arc. The isotopic characteristics that magma source regions in the southern part of the arc have higher Sr isotope rations have been maintained for at least the last 22 Ma.
    Fig 4. A plausible model for magma genesis along a volcanic front in subduction zones. Open arrows indicate the migration of H2O released from the subducted lithosphere and the dragged hydrated peridotites. SACP-HP= serpentine-amphibole-chlorite-phlogopite hydrous peri-dotite; ACP-HP=amphibole-chlorite-phlogopite hydrous peridotite; P-HP=phlogopite hydrous periotite; PMZ=partially molten zone from which mantle diaper starts rising; SCL=sub-continental lithosphere.