Dallol, Danakil Desert
Some have called this the “cruelest place on Earth.” Dallol is a volcano hidden beneath a kilometer-thick layer of salt in the Danakil depression in the Afar region, Ethiopia (at ~120 m below sea level). It manifests itself by an incredible variety of colorful springs and fumaroles in an alian landscape of salt, sulphur and other mineral deposits.
The term Dallol was coined by the Afar people and means dissolution or disintegration describing a landscape made up of green acid ponds ( pH-values less than 1) iron oxide, sulfur and salt desert plains.
Many volcanoes exist in the region, including Erta Ale and the Dabbahu Volcano.link
The Cave of Crystals
The Cave of Crystals (Cueva de los Cristales) is a chamber in the Naica Mine Located in Mexico, approximately 1,000 feet (300 m) down in the limestone host rock of the mine. The chamber contains giant selenite crystals, some of the largest natural crystals ever found.
Taklamakan is one of the largest sandy deserts in the world, is a paradigmatic cold desert climate. Given its relative proximity with the cold to frigid air masses in Siberia, extreme lows are recorded in wintertime, sometimes well below −20 °C (−4 °F). During the 2008 Chinese winter storms episode, the Taklamakan was reported to be covered for the first time in its entirety with a thin layer of snow reaching 4 centimetres (1.6 in), with a temperature of −26.1 °C (−15 °F) in some observatories.link
The Río Tinto
The Río Tinto is a river in southwestern Spain that originates in the Sierra Morena mountains of Andalusia. Since ancient times, a site along the river has been mined for copper, silver, gold, and other minerals.
As a result of the mining, Río Tinto is notable for being very acidic (pH 2) and its deep reddish hue is due to iron dissolved in the water.
This river has gained recent scientific interest due to the presence of extremophile aerobic bacteria that dwell in the water. These life forms are considered the likely cause of the high acid content of the water. The subsurface rocks on the river bed contain iron and sulfide minerals on which the bacteria feed.
The extreme conditions in the river may be analogous to other locations in the solar system thought to contain liquid water, such as subterranean Mars. NASA scientists have also directly compared the chemistry of the water in which the rocks of Meridiani Planum ( Mars ) were deposited in the past with the Río Tinto. link
The Chocolate Hills
The Chocolate Hills are an unusual geological formation in Bohol, Philippines. According to the latest accurate survey done there are 1,776 hills spread over an area of more than 50 square kilometres (20 sq mi). They are covered in green grass that turns brown during the dry season, hence the name.
These hills consist of Late Pliocene to Early Pleistocene, thin to medium bedded, sandy to rubbly marine limestones. These limestones contain the aboundant fossils of shallow marine foraminifera, coral, mollusks, and algae
Four legends explain the formation of the Chocolate Hills. The first tells the story of two feuding giants who hurled rocks, boulders, and sand at each other. The fighting lasted for days, and exhausted the two giants. In their exhaustion, they forgot about their feud and became friends, but when they left they forgot to clean up the mess they had made during their battle, hence the Chocolate Hills
A more romantic legend tells of a giant named Arogo who was extremely powerful and youthful. Arogo fell in love with Aloya, who was a simple mortal. Aloya’s death caused Arogo much pain and misery, and in his sorrow he could not stop crying. When his tears dried, the Chocolate Hills were formed.
The third legend tells of a town being plagued by a giant carabao, who ate all of their crops. Finally having had enough, the townsfolk took all of their spoiled food and placed it in such a way that the carabao would not miss it. Sure enough, the carabao ate it, but his stomach couldn’t handle the spoiled food, so he defecated, leaving behind him a mound of feces, until he had emptied his stomach of the food. The feces then dried, forming the Chocolate Hills.
The last legend is about a gluttonous giant named Dano that eats everything in his path. One day he came to a plain. He saw a beautiful young woman named Eng. To win her affection, he needed to lose weight. So he excreted everything he ate. In the end, his fecal matter covered the land and he won Eng’s affection. link
The mysterious holes of Sarisarinama
The Sarisarinama is situated on the edges of the Amazonas and Gran Sabana provinces in southern Venezuela. Also known as the Sarisarinama Tepuy, it stands as one of the remotest mountains in the whole of Latin America.
The Sarisarinama has always astonished people by its mysterious holes or the ‘simas’. These are huge perfectly circular stone depressions, which are 350 meters deep and 350 meters wide. Till date biologists and geologists have been amazed by the challenging mystery of the simas. Some believe that the simas are caused due to underground water erosion. To discover these holes, mountaineers start the climb from the northern side of Sarisarinama and reach the simas by foot. link
Stone Forest is a notable set of karst formations in Shilin Yi Autonomous County, in the Yunnan province of southwest China, approximately 85 km from the city of Kunming. The tall rocks seem to emanate from the ground in the manner of stalagmites, with many looking like trees made of stone, creating the illusion of a forest made of stone.link