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对大别山双河地区与超高压榴辉岩共生的黑云母片麻岩和围岩花岗质片麻岩进行了详细的氢、氧同位素研究。结果表明，这两种片麻岩在氧同位素组成上存在显著差别：黑云母片麻岩与共生的榴辉岩δ１８Ｏ值呈同步变化，全岩δ１８Ｏ值从－４．７‰变化至＋１０．３‰；花岗质片麻岩的δ１８Ｏ值变化范围较小，全岩δ１８Ｏ值为－４．２‰～＋０．８‰。这些片麻岩中不同矿物之间基本达到并保持了氧同位素平衡分馏，黑云母片麻岩中石英－多硅白云母和石英－石榴石矿物对的氧同位素温度分别为４２５℃～６３５℃和６２０℃～７６５℃，花岗质片麻岩中则分别为３９５℃～５４０℃和５６０℃～６２０℃，均与其角闪岩相退变质温度基本吻合。因此这两种片麻岩的实测δ１８Ｏ值代表了其变质原岩的氧同位素组成。两种片麻岩中含羟基矿物的氢同位素组成相似，绿帘石（和黝帘石）的δＤ值均落在－３７‰～－６４‰范围内，黑云母为－７８‰～－１０９‰。黑云母低的δＤ值指示了其中含有大气降水信息。岩石冷却过程中发生的同位素退化交换作用以及变质作用期间矿物反应对氧同位素漂移影响不大，因此黑云母片麻岩和花岗质片麻岩的１８Ｏ亏损是岩石在遭受角闪岩相变质作用之前与流体进行同位素交换作用的结果。应用稳定?
Hydrogen and oxygen isotope studies on biotite gneiss and granitic gneiss in the Shuanghe area of the Dabie Mountains and the UHP eclogite were carried out. The results show that there is a significant difference in the oxygen isotopic composition between the two gneiss: biotite gneiss and symbiotic eclogite δ18O values show a synchronous change, the whole rock δ18O value from -4.7 ‰ to +10.3 ‰. The range of δ18O value of granitic gneiss is small, and the δ18O value of whole rock is -4.2 ‰ ~ + 0.8 ‰. Oxygen isotope equilibria have been basically achieved and maintained between different minerals in these gneisses. Oxygen isotopes of quartz-polysiliciferous and quartz-garnet mineral pairs in biotite gneiss are 425 ℃ ~ 635 ℃ and 620 ℃ ~ 765 ℃, while the granitic gneisses are 395 ℃ ~ 540 ℃ and 560 ℃ ~ 620 ℃, respectively, which are consistent with the metamorphic temperature of amphibolite. Therefore, the δ18O values of these two gneisses represent the oxygen isotopic compositions of the metamorphic protoliths. The hydrogen isotopes of the hydroxygenic minerals in the two gneisses are similar in composition. The δD values of the epidote (and zoisite) fall within the range of -37 ‰ to -64 ‰ and the biotite -78 ‰ to -109 ‰ . The low δD values for biotites indicate that they contain precipitation information. The isotopic degenerate exchange during rock cooling and the mineral reaction during metamorphism have little effect on the oxygen isotope drift. Therefore, the 18O depletion of biotite gneiss and granitic gneiss is caused by amphibolite facies metamorphism The result of an isotope exchange with the fluid before. Application stability?