The Yangtze landmass collided with North China landmass due to Caledoniansubduction which happened after the ocean basin closed with Paleotethys subduction atEarly Palaeozoic. At last it developed Caledonian orogeny and caused borderland basinreversing.

• 早古生代洋盆随原特提斯的消亡,经加里东期的俯冲,扬子地块与华北地块碰撞,最终形成加里东俯冲造山带,由此导致陆缘盆地的反转。