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基于华北、扬子和塔里木三大地块最新古地磁结果,并重新审视已有的古地磁数据,绘制了三大地块显生宙以来的古地磁视极移曲线.以此为基础,推算了各地块古纬度和取向的变化特征.进而分析了三大地块及其周边地块的运动学特征及相互间的对接和缝合过程.早古生代,华北、扬子、塔里木地块都位于南半球中低纬度地区.华北地块在动力学上是独立的,其运动特征以平移为主,旋转运动为辅;扬子和塔里木地块与冈瓦纳大陆关系密切,塔里木地块很可能在晚奥陶世远离冈瓦纳大陆,在二叠纪与西伯利亚板块对接;我国华北和蒙古联合地块与西伯利亚板块的对接则是在晚保罗世完成的 扬子与华北地块的对接过程是先东后西,东部的对接发生在晚二叠世,对接时结合带位于北纬6°～8°.晚三叠世两地块在西部门合时,结合带位于北纬25°左右.两地块在西部对接的同时,在东部产生了应力释放,使最初俯冲到上地慢的部分陆壳物质被推挤上升,与苏鲁-大别地区的超高压变质岩形成的时代相同.从晚二叠世到早中侏罗世华北与扬子地块以东部为支点经历了大规模的相对旋转.晚侏罗世三大地块在动力学意义上已成为整体.在中国拉萨地块和印度次大陆与中国大陆对接缝合产生的力矩作用下.晚保罗世以来三大地块统一显示了约为20°的顺时针旋转运动.
Based on the latest paleomagnetic results of the three large blocks in North China, Yangtze and Tarim, and reexamining the existing paleomagnetic data, we plotted the paleomagnetic shift curve of the ancient magnetism since the Phanerozoic of the three major blocks. Based on this, The paleo-latitude and orientation of each block, and then analyzes the kinematic characteristics and the docking and stitching process of the three blocks and their surrounding blocks.Early Paleozoic, North China, Yangtze and Tarim blocks are located in the southern hemisphere Low latitude areas.The North China block is kinetically independent and its movement features are mainly translational and rotational movements, while the Yangtze and Tarim blocks are closely related to the Gondwanaland.The Tarim block is likely to occur in late Ordovician The world away from the Gondwana, docking in the Permian and Siberia plate; China North China and Mongolia joint plots and Siberia plate docking is completed in the late Paul Loose Yangtze and North China block docking process is the first east-west, In the eastern part of the junction occurred in the Late Permian, butt joint zone located at latitude 6 ° ~ 8 ° Late Ordovician two blocks in the western door closures, the junction zone located at latitude 25 ° north. At the same time, at In the eastern part of the island, some of the continental crust materials that were initially subducted to the upper slow are pushed up by the stress release, which is the same as that of the UHP metamorphic rocks in the Sulu-Dabie area.From the Late Permian to the Early Jurassic Large-scale relative rotation has taken place in the eastern North China and the Yangtze block with the eastern part as the fulcrum.The three Jurassic massifs have become a whole in the sense of dynamics.With the moment effect of the butt-jointing in the Lhasa block and the Indian subcontinent with China Under the unified protection of the three large blocks since the Late Paulian era, a clockwise rotation of about 20 ° has been shown.