摘要
郯庐断裂带中生代火山活动主要发生在早白垩世 ,形成了一套以橄榄安粗岩系为主的火山岩。火山岩岩石化学特征、地球化学特征与断裂带外明显不同 ,以富碱富钾、富轻稀土元素为特征 ,具有较高的 ISr值和明显偏低的εNd值 ,表明火山活动不仅与地壳混染有关 ,而且与深部地幔以及断裂带的演化有密切的关系。研究显示该区岩浆起源于地幔底侵、壳幔相互作用下的壳幔过渡带 ,也反映此时的断裂带切入到壳幔边界。
Mesozoic volcanic activities of the Tan Lu fault zone mainly appeared in Early Cretaceous and resulted in a set of volcanic rocks characterized by shoshonite series. The volcanic rocks are different from those outside of the fault zone in their geochemistry. They are rich in alkali, potassium and LREE, and have higher I Sr values and quite lowε Nd values. These features suggest that volcanic activities are not only related to crust contamination, but also to deep mantle and the fault zone's evolution. It is found that the magma originated from the transitional zone between the crust and mantle through underplating and mutual action of the crust and mantle and the fault zone cut into the boundary of the crust and mantle.
出处
《合肥工业大学学报（自然科学版）》
CAS
CSCD
2001年第2期147-153,共7页
Journal of Hefei University of Technology：Natural Science
基金
国家自然科学基金资助项目! (49872 0 74)
