Pb isotope composition of Klyuchevskoy volcano, Kamchatka and North Pacific sediments: Implications for magma genesis and crustal recycling in the Kamchatkan arc

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• 作者：Kersting ; Annie B. ; Arculus ; Richard J.
• 刊名：Earth and Planetary Science Letters
• 出版年：1995
• 出版时间：December, 1995
• 年：1995
• 卷：136
• 期：3-4
• 页码：133-148
• 全文大小：1.29 M

文摘

Pb isotope data are used to constrain the chemical contribution of the subducted components in the recycling beneath Klyuchevskoy volcano, the most active volcano in the Kamchatkan arc. The Pb isotope ratios of Klyuchevskoy basalts ( = 18.26-18.30, = 15.45-15.48, = 37.83-37.91) define a narrow range that falls within the Pacific mid-ocean ridge basalt (MORB) field and are among the least radiogenic island arc basalts measured to date. These data are similar to data from three other Quaternary Kamchatkan volcanoes: Tolbachik, Kumroch-Shish, and Maly Semiachik. In contrast, North Pacific sediments (primarily siliceous oozes) collected parallel to the Kamchatkan trench during Ocean Drilling Program Leg 145, have Pb isotope ratios ( = 18.51-18.78, = 15.56-15.64, = 38.49-38.75) that are more radiogenic than either the Klyuchevskoy basalts or Pacific MORB.