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对大别造山带不同产状大理岩的铅同位素研究表明,红安群王家店和双河大理岩分别经历过高压和超高压变质作用,具有较高的铅同位素变化范围和高的放射性成因铅,反映了上地壳铅同位素的特征;新店大理岩的铅同位素比值和变化范围很小,具有EM1型地幔铅同位素特征,表明有地幔铅同位素特征的记录;而位于剪切带的方高坪大理岩的铅同位素除了n(206Pb)/n(204Pb)值更高外,与新店大理岩的铅同位素特征相似,记录了放射性铅同位素的大量加入或丢失,导致本来具有与双河大理岩类似的铅同位素特征变得不明显。这些结果均表明大陆深俯冲及其折返过程对大理岩铅同位素组成的改造是相当复杂的。
The Pb isotope studies on different provenances of the Dabie orogenic belt show that the Wangandian and Shuanghe marbles in the Hongan Group experienced high pressure and ultrahigh pressure metamorphism respectively with high Pb isotopic variation and high radiogenic lead content , Reflecting the characteristics of lead isotopes in the upper crust. The lead isotopic ratios and variations of marble in Xindian marble are very small and have the characteristics of lead isotopes in the mantle of EM1, indicating the records of mantle Pb isotopic characteristics; Similar to the Pb isotopic characteristics of Xindian marble, the Pb isotopic composition of rocks, except for the higher n (206Pb) / n (204Pb) values, indicates the substantial addition or loss of radioactive Pb isotopes, The characteristics of lead isotopes become insignificant. These results indicate that the deep subduction of the mainland and its reentry process are quite complicated for the alteration of marble lead isotopic compositions.