Based on the late Paleozoic fold basement, Simao Triassic sedimentary basin formed in the early continental island arc colliusion stage after the close of Paleo Tethys ocean.

• 三叠纪沉积盆地建立在晚古生代褶皱基底之上，形成了古特提斯洋闭合后，造山早期的弧陆碰撞阶段。