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古生代含金刚石及捕虏体的金伯利岩和新生代含捕虏体的玄武岩先后共同侵位于华北地台东部,提供了研究自古生代以来板内岩石圈地幔特征及其演化的深源岩石探针。通过对古生代与新生代、新生代时郯庐断裂带内与带外岩石圈地幔物质之间岩相学,岩石和矿物的主元素、微量元素,地幔热状态的对比研究,结合现代地球物理资料,建立了以新生地幔物质对古老岩石圈置换作用为主的华北地台东部地幔减薄模型。该模型强调,古老岩石圈地幔业已存在的幔内薄弱带及郯庐断裂带为新生地幔物质和流体提供了通道。
The Paleozoic kimberlites containing diamond and xenoliths and the Cenozoic xenolith-containing basalts invaded the eastern part of North China Platform in succession and provided deep-source rock probes for studying the characteristics and evolution of intraplate lithospheric mantle since Paleozoic. By comparing the thermal state of the main elements, trace elements and mantle of lithofacies, rocks and minerals between the Palaeozoic and Cenozoic and Cenozoic terraces in the Tanlu fault zone and the out-of-band lithospheric mantle materials, and combining with the modern geophysical data , A model for the mantle reduction of the eastern North China platform based on the replacement of the ancient lithosphere by the new-born mantle material has been established. The model emphasizes that the existing mantle-derived weak zones in the ancient lithospheric mantle and the Tan-Lu fault zone provide access to the mantle material and fluids of the new mantle.