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对大别山西段苏家河地区熊店和杨冲低温榴辉岩及胡家湾榴闪岩进行了详细的氢、氧和锶、钕同位素以及稀土元素和矿物化学分析。熊店榴辉岩和胡家湾榴闪岩的全岩δ~(18)O值较高(8.8‰～11.2‰),而杨冲榴辉岩的全岩δ~(18)O价值较低(4.3‰),它们的全岩δD值均为-55‰～-75‰。结合锶、钕同位素和稀土元素组成特征,推测苏家河榴辉岩(榴闪岩)的原岩可能为岛弧玄武岩,变质前曾与海水在不同温度下进行过氢、氧同位素交换。苏家河榴辉岩围岩大理岩的δ~(13)C值较低(-2.6‰～0.1‰),与大别山东段大理岩δ~(13)C(0.5‰～5.7‰)较高明显不同,反映其原岩灰岩沉积环境存在差异。熊店大理岩的δ~(18)O值低达2.0‰～2.2‰,说明岩石在成岩—变质作用过程中曾与低δ~(18)O流体(可能是大气降水)发生过相互作用。
The hydrogen, oxygen, strontium and neodymium isotopes, as well as the REE and mineral chemical analyzes of Xiongdian and Yangchong low-temperature eclogite and Hujiawan amphibolite in the western part of the Dabie Mountains were analyzed. The δ 18 O value of the Xiongdian eclogite and the Hujiadian amphibolite is relatively high (8.8 ‰ ~ 11.2 ‰), whereas that of the Yangchong eclogites is relatively low (4.3 ‰), their δD values of all rocks are -55 ‰ ~ -75 ‰. Based on the composition of strontium, neodymium isotope and REE, it is speculated that the original rock of the eclogite (slick rock) in Sujiahe may be island-arc basalt. Before metamorphism, hydrogen and oxygen isotopes were exchanged with seawater at different temperatures. The δ 13 C values of the marble rocks of the eclogite from the Sujihe area are relatively low (-2.6 ‰ ~ 0.1 ‰), which are significantly different from the δ 13 C (0.5 ‰ -5.7 ‰) of the marble of the eastern segment of the Dabie Mountains , Reflecting the difference between the original rock limestone sedimentary environment. The δ 18 O value of Xiongdian marble is as low as 2.0 ‰ ~ 2.2 ‰, which indicates that the rock interacted with low δ 18 O fluid (possibly atmospheric precipitation) during its diagenesis and metamorphism.