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本文在讨论中国东部现有构造演化模式基础上,着重从华北与华南地块之间板块尺度的动力学过程剖析秦岭—大别中生代造山带构造演化,以及大别—苏鲁超高压变质地体的形成和折返过程。晚二叠世一中三叠世华南地块向华北地块持续挤压,陆壳大规模俯冲导致超高压变质作用的产生,而华北地块在晚三叠世至早保罗世发生快速逆时针旋转,使大别—苏鲁带由挤压转为张扭性环境,使得这一地区上地幔深度的超高压变质地体快速折返至下地壳。由于超高压变质地体侵位后,地壳结构、构造的差异,在南北地块的进一步挤压下,造成中国东部晚侏罗世—早白垩世郯庐断裂带的巨大左行剪切。
Based on the discussion of the existing tectonic evolution patterns in eastern China, this paper focuses on the tectonic evolution of the Qinling-Dabie Mesozoic orogenic belts and the formation of the Dabie-Sulu UHP metamorphic terrane from the dynamics of plate-scale dynamics between the North China and South China blocks And the return process. The Late Triassic-Middle Triassic South China block continued to squeeze into the North China block, resulting in the occurrence of UHP metamorphism by the large-scale subduction of the continental crust. However, rapid counterclockwise rotation of the North China block occurred from the Late Triassic to the Early Paul Roce Rotation, so that the Dabie-Sulu belt from compression to tension and torsional environment, making the region of the upper mantle depth of ultra-high pressure metamorphic body quickly reverted to the lower crust. Due to the difference in crustal structure and structure after the emplacement of the UHP metamorphic body, further left-lateral shearing of the Late Tanuchi-Early Cretaceous Tan-Lu fault zone in eastern China resulted from the further extrusion of the northern and southern blocks.