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原岩是辉长岩的含柯石英榴辉岩,其超高压变质作用将在“干”条件下进行,矿物具有较高的封闭温度,并能观察到Nd同位素不平衡现象.若榴辉岩原岩是变玄武岩,在超高压变质时,角闪石将分解并释放出水,因而矿物Nd同位素封闭温度较低,并可达到Nd同位素平衡.岩石后期蚀变及与深部流体的相互作用是影响Sm-Nd定年的最主要因素.大别山含柯石英榴辉岩的可靠Sm-Nd同位素年龄集中在221～232Ma,虽然数值略低,但接近榴辉岩的峰期变质时代.苏家河低温榴辉岩有可能是古生代洋壳俯冲成因.
The original rock is a gabbro-bearing eclogite of gabbro, and its UHP metamorphism will be carried out under “dry” conditions, the minerals have a high sealing temperature and Nd isotope imbalance can be observed. If the eclogite Rocks are basaltic rocks, and amphiboles will decompose and release water during the UHP metamorphism, resulting in a lower Nd isotope closure temperature and Nd isotope balance.The late rock alteration and interaction with deep fluids is responsible for the effects of Sm The most important factor for the dating of Nd isotopes.The reliable Sm-Nd isotopic age of the coesite-bearing eclogites in the Dabie Mountains is concentrated in the range of 221-232 Ma, although the value is slightly lower, but close to the eclogitic epoch of the eclogite. It may be due to the subduction of the Paleozoic oceanic crust.