One of the best examples of colorful landform is on Mount Danxia, in Guangdong Province, in China. The Danxia landforms are made of strips of red sandstone alternating with chalk and other sediments that were deposited over millions of years, like slices of a layered cake. Over 700 individual locations have been identified in China, mostly in southeast and southwest China, where this type of colors and layers can be seen—all of these are referred to as Danxia landforms.
The Hill of Seven Colors, Purmamarca
About 70 km south of Humahuaca is another rainbow-colored hill—Cerro de los Siete Colores, or the Hill of Seven Colors, located near the tiny village of Purmamarca, in north-western Argentina. The hill was formed by a complex geological process that involved deposition of sea, lake and river movements and subsequent elevation of the land due to the movement of the tectonic plates about seventy-five million years ago. It is said that you can see seven colors in the hill, but most people can pick out only four. The colors are most clearly visible in the morning.
The Ausangate mountain, about 100 kilometers southeast of Cusco, in Peru, is also known as Rainbow Mountain or Cerro Colorado because of its exposed layers of rock bearing red, ochre, and turquoise colors. The mountain is 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. Every year thousands of Quechua pilgrims visit the Ausangate Mountain for the Star Snow festival which takes place a week before the Corpus Christi feast.
Painted Hills of Oregon
The colorful layers and banded striations that make up the Painted Hills in Wheeler County, Oregon, the United States of America, were formed over 35 million years ago by volcanic ash layers deposited by ancient eruptions when the area was a river plain. Over time, the layers of ash containing different minerals compacted and solidified into the various bands of colors seen today. The black soil is lignite that was vegetative matter that grew along the floodplain. The grey coloring is mudstone, siltstone, and shale. The red and orange hues are from laterite soil that formed by floodplain deposits when the area was warm and humid.
The Red Earth Terraces of Dongchuan
Some 250 kilometers northeast of Kunming, the capital of China’s Yunnan Province, lies Dongchuan, a rural area with the world’s most imposing red earth. Spread over vast terraced fields, Dongchuan’s unusual brownish-red color comes from its rich deposit of iron and copper. Exposed to the warm and humid climate of Yunnan, the iron in the soil undergoes oxidization to form iron oxide which is naturally red in color. These oxides, deposited through many years, gradually developed into the extraordinary reddish brown soil seen here today. Every year during spring, when this area is ploughed for agriculture, a large number of visitors and photographers come to see squares of freshly upturned red earth waiting to be sown along with areas of budding green plants. The fiery red soil juxtaposed with emerald green barley, and golden yellow buckwheat, against a blue sky produces one of the richest color palate rarely seen in nature.