Rainbow Mountains, China’s Zhangye Danxia Landform Geological Park in Gansu Province
The mountains’ vibrant colors came from water and oxygen interacting with iron and other elements in the sediment, along with tiny amounts of other minerals left behind by groundwater creeping through the deposits.
Over millions of years, the layers were buried and solidified into rock. Their slant was caused by the same tectonic forces responsible for the formation of the Himalayas: as the Indian plate crashed into the Eurasian plate, beginning about 40 or 50 million years ago, the overlying land tilted and crumpled into mountains.
And that is just the way it is... interaction... crumpling over millions of years... wow factor...