近日，英国朴茨茅斯大学Daniel Gómez-Frutos团队揭示了大陆演化受深俯冲大陆地壳再分层影响。2026年5月5日出版的《自然—地球科学》杂志发表了这一最新研究成果。

自30亿年前的太古代以来，后碰撞岩浆作用在改造大陆地壳方面发挥了关键作用。钙碱性后碰撞岩浆的双重地幔-地壳印记要求一个混合了两个储库的源区，但该混合源区的形成机制尚不清楚。

研究组采用热-力学与岩浆实验相结合的综合方法来约束地幔-地壳混合及后碰撞岩浆作用的地球动力学成因，揭示了它们与大陆岩石圈俯冲过程的关联。该数值模型预测，由于俯冲的富硅地壳与下覆大陆岩石圈发生解耦，深俯冲的大陆地壳会广泛再层析到上覆板块的底部。在这种背景下，后碰撞岩浆作用源于再层析地壳与地幔橄榄岩高效机械混合后形成的混合域。

该实验室熔融实验证明，来自该混合源的岩浆产物能够再现后碰撞火成岩的自然成分演化趋势。再层析地壳与岩石圈地幔之间的这种机械-化学相互作用，记录在地球历史中的岩浆同位素特征中；并且，由于显生宙后碰撞钙碱性岩石与太古代赞岐岩类之间的相似性，这意味着地壳-地幔混合过程自前寒武纪板块构造运动以来就已存在。

附：英文原文

Title: Continental evolution influenced by relamination of deeply subducted continental crust

Author: Gmez-Frutos, Daniel, Castro, Antonio, Balzs, Attila, Gerya, Taras

Issue&Volume: 2026-05-05

Abstract: Post-collisional magmatism has played a critical role in modifying the continental crust since the Archaean, 3 billion years ago. The dual mantle–crust signature of calc-alkaline post-collisional magmas requires a hybrid source involving both reservoirs, the formation of which is not well understood. Here we use an integrated thermomechanical and magmatic experimental approach to constrain the geodynamic causes of mantle–crust hybridization and post-collisional magmatism, which reveals their association with subduction of continental lithosphere. Our numerical models predict pervasive relamination of deeply subducted continental crust onto the base of the overriding plate, owing to the decoupling of the buoyant silica-rich crust from the subducting continental lithosphere. In this setting, post-collisional magmatism is sourced from a hybrid domain following efficient mechanical mixing between the relaminated crust and mantle peridotite. Our laboratory melting experiments demonstrate that the magmatic products from this hybrid source reproduce the natural compositional trend of post-collisional igneous rocks. This mechanical–chemical interaction between relaminated crust and mantle lithosphere is recorded in magmatic isotopic signatures throughout Earth’s history and, given the similarity between Phanerozoic post-collisional calc-alkaline rocks and Archaean sanukitoids, implies that crust–mantle hybridization has occurred since Precambrian plate tectonics.

DOI: 10.1038/s41561-026-01963-w

Source: https://www.nature.com/articles/s41561-026-01963-w