本文提出了一种基于地层年代、岩石系列和关联特征的模型，探讨了侏罗纪时期中国大陆内部岩浆活动与泰塔尼亚构造带的碰撞与下潜，以及太平洋构造带古太平洋板块俯冲-剪切扩展的关系。研究时段分为220-150Ma和145-90Ma，分别对应华北和扬子地块的水平碰撞及华南西南部微型大陆板块的内潜，以及受泰塔尼亚构造背景下的太平洋板块俯冲-滑动扩展影响的岩浆活动类型和分布。华南沿海的A型碱性岩浆出现标志着中生代大陆内生岩浆活动的结束。
摘要：
The authors have proposed a dynamic model in this paper based on the ages,rock series 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 regie with Paleo-Pacific oceanic plate sudbuction-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 South China are ascribed to the influence of the Tethyan tectonic regime,giving rise to a volume of high-Isr and low-εNd(t) S-type granites only in the Cathaysian Block.During 145-90Ma,under the geodynamic backgound of subduction-strike slip-extension of the Paleo-Pacific oceanic plate on the basis of the deep tectonic process in the Tethyan tectonic regime,high-K,alkalirich calc-alkaline and shoshonitic volcano-plutonic complexes were generated in the Yangtze block,and high-K calc-alkalic and bimodal volcano-plutonic complexes were generated in the Cathaysian block.The occurrence of A-type peralkaline granites in the coastal areas of South east China indicates the end of Mesozoic intracontinental magmatism.
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