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对汉诺坝玄武岩携带的条带状麻粒岩锆石进行了背散射、Hf同位素、U-Pb年龄和微量元素原位分析. 结果表明: 条带状麻粒岩为早期下地壳样品, 其成因很难用单一的过程来解释, 而是包含着地壳再熔融岩浆作用、幔源物质参与、变质分异作用和早期的下地壳拆沉作用等复杂过程信息. 岩石中除有3097~2824和2489~2447 Ma的古老年龄信息外, 80%的锆石给出1842±40 Ma的年龄值. 老年龄锆石有高的eHf值(达+18.3)和高的Hf模式年龄(2.5~2.6 Ga), 说明形成该岩石的初始物质主要来源于晚太古代的亏损地幔. 早元古代锆石的eHf值多变化于零附近; 个别有较高的eHf值(+9.2~+10.2), 表明早元古代时华北东、西部地块碰撞拼合并导致克拉通最终形成过程中有地幔物质参与.
Backscattering, Hf isotope, U-Pb ages and trace elements in situ of the banded granulite zircons carried by the Hannuoba basalts show that the banded granulites are early crustal samples, Genesis is difficult to explain with a single process, but contains complicated processes such as crustal re-melting magmatism, mantle-derived material involvement, metamorphism and early crust de-sinking, etc. In addition to 3097-2824 and For ages 2489 to 2447 Ma, 80% of the zircons give an age of 1842 ± 40 Ma, while older zircons have high eHf values (up to +18.3) and high Hf ages (2.5 to 2.6 Ga ), Indicating that the initial material forming the rock is mainly derived from the late Archean depleted mantle.The eHf values of Early Proterozoic zircons changed around zero, and the individual eHf values were higher (+ 9.2 ~ + 10.2) During the Proterozoic, collisions and collisions of the eastern and western parts of North China resulted in the involvement of mantle materials during the final formation of craton.