Nd Isotopic Compositions of Metamorphic and Granitic Rocks from Dabie Orogen and Their Geological Significance
大别造山带变质岩和花岗岩的钕同位素组成及其地质意义

Sin-Nd isotopic compositions of 8 metamorphic rock samples and 4 granite samples of Dabie orogen suggest that the Nd model ages are different in different tectonic units. Generally, the Nd model ages of the rocks of North Dabie Terrain(NDT)are older than those of Ultrahigh-pressure(UHP)block in South Dabie. However,Nd model ages of metamorphic rocks from UHP block vary widely. The range of Nd (122Ma) of the granites intruding into different tectonic units is the same of that of NDT metamorphic rocks.It suggests that these rocks have similar sources.Therefore,the UHP block is a slab over the older metamorphic rocks.