拉伸纪是Rodinia超大陆形成及开始裂解的时期，同时这一时期也是地球各个圈层系统发生剧烈转变的时期。现阶段对Rodinia超大陆的形成过程、形成时间及裂解的过程和时间仍存在很大的争议，因而严重影响了对于拉伸纪地球系统相互作用的理解。近年来，古地磁研究表明这一时期存在多期的真极移事件，这为理解Rodinia超大陆的形成演化及地球各圈层的相互作用提供了重要的依据。然而，现有这一时期的真极移记录仍较少，仅华南、Svalbard（Laurentia）有记录，且有一定的差别。因此加强这一时期华南板块的古地磁研究，不仅可以确定这一时期真极移事件的具体形式，同时由于真极移事件的全球同步性，也可以利用真极移数据更精准的重建Rodinia超大陆。进而在此基础上去研究地球各圈层在这一时期的相互耦合关系。

The Tonian period witnessed the assembly and breakup of Rodinia and the dramatical evolution of earth's multiple spheres. Nowadays, there is hotly debated that how and when the Rodinia assembly and breakup, which hinders our understanding about the dramatical evolution of earth's multiple spheres during this time. Recent paleomagnetic studies demonstrate there occurred multiple times of True polar Wander events during this time, which can shed light on these issues. However, only South China and Svalbard (Laurentia) recorded these True polar Wander events, and their records are little different from each other. Therefore, paleomagnetic study on the Tonian strata of South China will not only clarify the details about these true polar events, but also can refine the evolution of the Rodinia. Besides that, due to the relationship of the true polar wander and the mass distribution of the planet, we also can talk about the coupled relationship of the multiple spheres of Earth.