Xiaokhai Tiankeng: the largest sinkhole in the world
(Image credit: Design Pics Inc/Alami)
It was only “discovered” by the outside world in 1994, and experts are still not sure how it was created.
Looking down from space at the rolling green landscape of the rural Chongqing municipality in southwest China, a series of deep, dark gashes appear, indenting the earth like an alien footprint. Some experts wonder if these mysterious formations are the result of a meteorite falling to Earth. Others believe they formed gradually over some 128,000 years, as water seeping into underground rivers slowly carved the surrounding limestone rock in its path.
But one thing is certain: with a depth of 660 meters, with a volume of 130 million cubic meters, China’s Xiaokhai Tiankeng is both the deepest and largest sinkhole in the world.
Video: The deepest sinkhole in the world
Tiankeng means “Heavenly Pit”, and its very sides drop precipitously into a veritable netherworld that is home to a thriving ecosystem of some 1,285 plant and animal species – including rare gingko and clouded leopards. In addition to its enormous size, the formation is also unique in that it is a double-nested sinkhole that holds two craters connected by a sloping rim. In the rainy season, a waterfall cascades from the mouth of the pit, feeding an underground river and a network of caves at its base.
While local residents have known about the sinkholes for centuries, they were only “discovered” by the outside world in 1994, when British researchers attempted to probe its labyrinth-like underground cave system. Despite attempts to map the underground river five times over a 10-year period, cavers found the gushing torrent too difficult to navigate and the team never succeeded. As a result, this deep, dark underground remains one of China’s great geological mysteries.
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