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大陆岩石圈根的形成与破坏是当前固体地球科学的重大研究课题之一.对独具时空特色的华北东部地块南缘信阳中生代火山岩中一系列包括下地壳镁铁质-长英质的麻粒岩、榴辉岩、变辉长岩、辉石岩和上地幔橄榄岩等岩石包体进行了系统的定深、定年研究,建立了华北中生代(～160Ma)多块体结合部位的组成和年龄呈带状结构的岩石圈几何模型,并在此基础上分析了形成的动力学过程.在华北南缘地表出露最老～2.85Ga的岩石之下的30km处(上部下地壳),由年龄为3.6～3.4Ga的长英质麻粒岩和辉石岩组成;更深处30～40km位置,则由具古元古代年龄(2.0～1.8Ga)的镁铁质-长英质麻粒岩和变辉长岩构成,其形成过程与华北东部地块与西部地块的碰撞有关,记录着全球性的哥伦比亚超大陆汇聚事件.Hf同位素数据显示在这次重要事件里,既有新生地幔物质加入,也有古老地壳(3.8～3.0Ga)组分的再熔融作用.在来自下地壳更深处的榴辉岩(40～45km)和上地幔橄榄岩(>45km),它们的主要年龄分别是古生代(440～260Ma)和早中生代(228～219Ma),记录着在显生宙不同时期扬子与华北碰撞的动力学过程.
The formation and destruction of continental lithospheric roots are one of the major topics in current solid earth science research.A series of volcanic rocks in the Xinyang volcanic rocks in the southern margin of the eastern part of North China, Granulite, eclogite, gabbro, pyroxenite and upper mantle peridotite were systematically studied by deep-sea and long-term studies. The composition of the multi-block binding sites of Mesozoic (~ 160 Ma) Age belt-like lithosphere geometric model, and on the basis of which the dynamic process of formation was analyzed.At 30km below the rock with the oldest ~ 2.85Ga surface exposed on the southern margin of North China, Age of 3.6 ~ 3.4Ga of the British quartz granulite and pyroxene composition; deeper 30 ~ 40km position, the age of the ancient Paleozoic (2.0 ~ 1.8Ga) mafic - feldspar granulite And gabbro, and its formation process is related to the collisions between the eastern North China block and western block, recording the global Columbia continental convergence event.Hf isotope data show that in this important event, both newborn mantle material Join, there are ancient crust (3.8 ~ 3.0Ga) (40 ~ 45km) and upper mantle peridotite (> 45km) deeper from the lower crust, the main ages are Paleozoic (440-260 Ma) and Early Mesozoic (228-219 Ma) ), A record of the dynamics of the collision between the Yangtze and North China at different Phanerozoic ages.