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The authors have proposed a dynamic model in this paper based on the ages, rock se ries and associations, Sr-Nd isotopic signatures of the Mesozoic intracontinental magmatismoverlying the Cathaysian and Yangtze blocks. The model describes the relation of intracontinental collision and subduction in the Tethyan tectonic regime with Paleo-Pacific oceanic platesubduction-strike slip-extension in the Pacific tectonic regime. During 220 - 150Ma, the horizontal collision between the North China block and the Yangtze block, as well as the intracontinental subduction of some divergent microcontinental terranes in the southwestern part of SouthChina are ascribed to the in fluence of the Tethyan tectonic regime, giving rise to a volume ofhigh-Isr and low-ENd(t) S-type granites only in the Cathaysian block. During 145 - 90 Ma, under the geodynamic background of subduction-strike slip-extension of the Paleo-Pacific oceanicplate on the basis of the deep tectnic process in the Tethyan tectonic regime, high-K, alkali-rich calc-alkaline and shoshonitic volcano-plutonic complexes were generated in the Yangtzeblock, and high-K calc-alkalic and bimodal volcano-plutonic complexes were generated in theCathaysian block. The occurrence of A-type peralkaline granites in the coastal areas of South-east China indicates the end of Mesozoic intracontinental magmatism.
The authors have proposed a dynamic model in this paper based on the ages, rock se ries and associations, Sr-Nd isotopic signatures of the Mesozoic intracontinental magmatism overlying the Cathaysian and Yangtze blocks. The model describes the relation of intracontinental collision and subduction in the Tethyan tectonic regime with Paleo-Pacific oceanic plates plateduction-strike slip-extension in the Pacific tectonic regime. During 220 - 150Ma, the horizontal collision between the North China block and the Yangtze block, as well as the intracontinental subduction of some divergent microcontinental terranes in the Southwestern part of SouthChina are ascribed to the in fluence of the Tethyan tectonic regime, giving rise to a volume of high-Isr and low-ENd (t) S-type granites only in the Cathaysian block. During 145 - 90 Ma, under the geodynamic background of subduction-strike slip-extension of the Paleo-Pacific oceanic plate on the basis of the deep tectnic process in the Tethyan tectonic regim e, high-K, alkali-rich calc-alkaline and shoshonitic volcano-plutonic complexes were generated in the Yangtzeblock, and high-K calc-alkalic and bimodal volcano-plutonic complexes were generated in the Chahaianian block. The occurrence of A-type peralkaline granites in the coastal areas of South-east China indicates the end of Mesozoic intracontinental magmatism.