Great works of art take time. The Zhangye Danxia hills in China have been crafted and perfected by nature over the past 24 million years, by the same collision of the Indian and Eurasian plates that produced the Himalaya. Eroding over time, at about eight metres a century, the red sedimentary, siltstone, and siliciclastic rock was pushed to the surface and exposed, painting this region with a “cake layer effect”.
Historically, the Zhangye area was a thriving economic centre, vital to the Silk Road. Here, the Emperor Shuiyang of the Shui dynasty held his famous World Exposition. Even Marco Polo spoke highly of its vibrant culture.
Photo: Shutterstock
The newly created geopark is divided into two main areas: the 510 square kilometre Zhangye Qicai (meaning seven colors) Danxia Scenic Area and the 332 square kilometre Bing Gou (meaning ice valley).
Much earlier in geological time, oceans and lakes covered the region. Over the millennia, the waters evaporated and left behind large deposits of sand to solidify and bear the brunt of the elements.
On the Inner Mongolian border
The Danxia landforms only occur in southeast, southwest, and northwest China. The Zhangye Danxia lies 1,700km from Beijing and 30km from the city of Zhangye and forms part of the Qilian Mountain Range, which almost ventures into Mongolia territory. Its otherworldly red valleys include plunging gorges, jagged pillars, cliffs, and natural pyramids.
The word Danxia translates naturally enough as rosy cloud. Two processes are responsible for the amazing phenomenon. First, it was supposedly formed between the Jurassic and Cretaceous periods, a time of great weathering in arid deserts. Weathering stripped away the rock to reveal the more complicated layering underneath.
The otherworldly landscape formed over 24 million years. Photo: Shutterstock
An artist’s palette of oxides
The startling red, brown, yellow, and green sandstones that fold over each other are due to the presence of various oxides. The red sandstone contains iron oxide; yellow, iron sulfide; green, chlorite; brown, oxidized limonite. These chemical compounds react with the minerals present in groundwater, which has penetrated the sandstone grains and cemented. This water carries trace minerals which cause this colorful reaction, staining the Danxia and streaking across the landscape like brushstrokes on a canvas.
While the Danxia landform is native to China, other colorful geological formations around the world include the Rainbow Mountains of Peru, the Spectrum Range of British Columbia, and the Rainbow Range in the United States. The Zhangye Danxia was made a UNESCO World Heritage Site in 2009 and is considered one of the most beautiful locations in China.
