岩石圈演化具有准周期25亿年、12-13亿年及6-8亿年巨旋回,其对应地质时代“宙”,对应地层单位“宇”。其根源是:河外星系之大、小麦哲伦星云以准周期25亿年围绕银河系旋转,引起地球的黄赤交角(ε)由0°到360°作准周期25亿年变化,且二者又引起:岁差转矩与潮汐转矩大小各以准周期12-13亿年变化且二者峰值交替出现(即对地 Lithosphere evolution with a quasi-2.5 billion years, 12-13 billion years and 6-8 billion years of giant gyration, which corresponds to the geological era “universe”, corresponding to the unit “Yu.” Its origins are: the extragalactic galaxy, the small Magellanic nebula revolves around the Milky Way at a quasi-2.5 billion year-cycle, causing a change in the Earth’s yellow-red angle (ε) from 0 ° to 360 ° for a period of 2.5 billion years, The magnitude of torque and tidal torque each vary by 1.2-13 billion years in quasi-cycle and the two peaks alternate (ie, to ground