Sichuan Basin

From Wiki China org cn

Situated in the Sichuan-Chongqing area, the basin is surrounded by Wushan and Dabashan mountains and covers 200,000 square km. With its base averaging 300-800 meters above sea level, it has a terrain descending from the north to the south. Its northwestern part is Chengdu Plain, and its central and eastern parts are hills and low mountains. Teeming with purplish red sandstones, it is also known as a "purple basin."