张八岭隆起南缘早白垩世火山岩稀土元素对比研究

张八岭隆起南缘早白垩世火山岩与北大别山东部、庐枞盆地、鲁西同期火山岩同属于中国东部岩石圈伸展减薄背景下形成的火山岩。然而稀土元素地球化学特征却反映出，张八岭隆起南缘火山岩来源于壳幔过渡带。而北大别山东缘同期火山岩与岩浆上升过程中地壳物质的混染有关，庐枞盆地火山岩岩浆来自与俯冲洋壳有关的富集地幔部分熔融，鲁西地区火山岩岩浆与俯冲的陆壳在地幔源区发生混染和交代形成的富集型地幔部分熔融有关。稀土元素研究的结果与构造背景、微量元素以及Sr，Nd同位索等研究相吻合，进一步表明稀土元素在火山岩岩浆来源方面有很好的示踪作用。岩浆的来源不同以及研究区大型断裂的作用正是张八岭隆起地区成为金矿成矿远景区的重要原因。

Comparative Studies of Rare Earth Elements for Early Cretaceous Volcanic Rocks along the Southern Segment of Zhangbaling Uplift Belt

Early Cretaceous volcanic rocks in the southern segment of the Zhangbaling uplift belt and those along the eastern part of the North Dabie Mountains, the Luzong basin, the western Shandong Province belong to the same tectonic setting of lithospheric extension and thinning in eastern China. However, characteristics of rare earth elements show that volcanic rocks in the southern segment of the Zhangbaling uplift belt originate from the transitional zone between the crust and mantle, those in the eastern part of the North Dabie Mountains are related to crustal material contamination during magma ascending, the magma of the volcanic rocks in the Luzong basin is derived from the partial melting of the enriched mantle related to subducted oceanic-crust minerals, the magma of the volcanic rocks in western Shangdong Province comes from the partial melting of the enriched mantle affected by contamination and metasomatism of the subducted continental-crust. Therefore, the research results of the rare earth elements coincide with the studies of tectonic setting, incompatible elements and Sr, Nd isotopes. It is further indicated that the rare earth elements offer effective approach to tracing the material sources of volcanic rocks. The different origin of magma and effect of the Tan-Lu fault zone should be an important deep mason for association with Au-mineralization in the Zhangbaling uplift belt.