One of the most magnificent geologic features in the world is the Ausangate Mountain of the Peruvian Andes. The mountain is striped with colors ranging from turquoise to lavender to maroon and gold. However, this "painted mountain" is notoriously difficult to find and get to, requiring several days of hiking to reach its peak deep within the Andes by way of Cusco. The painted Ausangate mountain is also considered to be holy and believed to be the deity of Cusco by local Peruvians. It is a site of daily worship and offerings by local citizens. Welcome To The Incredible Rainbow Mountains Of Peru
The reason we see the rainbow coloration in the stratigraphic layers of the Ausangate mountain is largely due to weathering and mineralogy. Red coloration of sedimentary layers often indicates iron oxide rust as a trace mineral. Similar to how a nail will rust and turn red when oxidized, sediments that are iron rich will change when exposed to oxygen and water. This, in combination with uplift and tectonically driven crustal shortening has tilted the sedimentary layers on their side exposing stripped stratigraphic intervals. The different coloration is due to different environmental conditions and mineralogy when the sediment was originally deposited and subsequently diagenetically altered. Introduction of goethite or oxidized limonite will introduce a brownish coloration to sandstones. The bright yellow coloration could be due to iron sulphide as trace minerals within the pore cement. In addition, chlorite will often color sediments varying shades of green dependent on diagenetic history and concentration.