Relationship between Mesozoic magmatism and subduction in the Da Hinggan-Yanshan area

High-resolution tomographic images of the belt crossing the Japan Trench-Ch angbai Mountains-Dong Ujimqin Qi are represented in this paper, revealing t he shape of a subducted slab in the western Pacific region and characterist ics of the lithospheric structures under the Changbai Mountains and the Da Hinggan Mountains. Studies of the spatial distribution, subduction time and the time-lag between the subduction and magmatism, combined with petrology and isotope geochemistry of the Late Mesozoic volcano-plutonic rocks from the Da Hinggan Mountains-Yanshan Mountains have further proved the independ ence of magmatic activities from the subduction of the Pacific plate. The M esozoic tectono-thermal evolutionary history and structural characteristics of the lithosphere in the Da Hinggan Mountains and North China suggest tha t the formation and evolution of magma have probably a close relationship w ith the delamination and thinning of the continental lithosphere and the un derplating resulting from the consequent upwelling of the asthenosphere. On the other hand, the large-scale strike-slip fault system, resulting from s inistral shearing of the Pacific plate relative to the Asian continent in t he Mesozoic, is responsible for the formation and emplacement of magma on t he continental margin. It was the intense crust-mantle interaction, togethe r with structural deformation at the shallower levels that led to the large tectono-magmatic belt in the East Asian continental margin.