A team of Chinese scientists have discovered a huge new sinkhole with a forest at the bottom.
The sinkhole is 630 feet (192 meters) deep, according to Xinhua News Agency, deep enough to swallow only the Arch of St. Louis. A team of accelerators and explorers entered the sinkhole on Friday (May 6), discovering that there are three cave entrances in the abyss, as well as ancient trees 131 feet tall ( 40 m), stretch its branches towards sunlight shining through the entrance to the sinkhole.
“This is exciting news,” said George Veni, executive director of the National Karst and Cave Research Institute (NCKRI) in the US and an international expert on caves. Veni is not involved in cave exploration, but the organization, the Karst Institute of Geology of the China Geological Survey, is the sister institute of NCKRI.
A site for sinkholes
The find, Veni told Live Science, is not surprising because southern China is home to karst terrain, a landscape prone to dramatic sinkholes and otherworldly caves. Veni said that the Karst landscape was formed mainly by the decomposition of the bedrock. Rainwater, slightly acidic, rising up carbon dioxide as it runs through the soil, becomes more acidic. It then dripped, darted, and flowed through cracks in the bedrock, slowly expanding them into tunnels and voids. Over time, if a cave chamber is large enough, the ceiling can gradually collapse, opening huge sinkholes.
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“Due to local differences in geology, climate and other factors, the way karsts appear on the surface can be very different,” he said. “So in China, you have this incredibly spectacular limestone mountain with huge sinkholes and huge cave entrances, etc. Elsewhere in the world, you step out of the limestone and you really didn’t notice anything. The sinkholes can be quite intrusive, only a meter or two in diameter. The entrances to the caves can be very small, so you have to wriggle to get into them.”
In fact, 25% of the United States is karst or pseudokarst, which has caves created by factors other than dissolution, such as volcanoes or winds, Veni said. About 20% of the world’s land area is made up of one of these two cave-rich landscapes.
According to Xinhua, the new discovery took place in Guangxi Zhuang Autonomous Region, near the village of Ping’e in Leye county. Guangxi is known for its amazing karst formations, which range from sinkholes to stone pillars to natural bridges and have earned the area a reputation UNESCO recognized world heritage.
Why are sinkholes important?
Zhang Yuanhai, a senior engineer with the Karst Institute of Geology, told Xinhua that the interior of the sinkhole is 1,004 feet (306 m) long and 492 feet (150 m) wide. The Mandarin word for such giant sinkholes is “tiankeng,” or “heavenly pit,” and the bottom of the sinkhole really feels like another world. Chen Lixin, the leader of the caving team, told Xinhua that the thick layer of bushes on the floor of the sinkhole was as high as a person’s shoulder. Caves and sinkholes can provide oases for life, Veni says.
“I wouldn’t be surprised to learn that there are species found in these caves that have never been reported or described by science to date,” Lixin said.
In a cave in West Texas, Veni said, tropical ferns grow in abundance; The fern’s spores appear to have been carried to shelters by bats migrating to South and Central America.
Sinkholes and caves are not only hiding places for life, they are also a path to aquifers, or deep underground storages of water. Karst aquifers provide the primary or sole source of water for 700 million people worldwide, Veni said. But they are easily accessed and drawn – or polluted.
“Karst aquifers are the only type of aquifer that you can pollute with solid waste,” Veni said. “I’ve pulled car batteries, trunks, and God-know-it containers and God-know-what bottles out of a working stream.”
According to Xinhua, the new discovery brings the number of sinkholes in Leye district to 30. Similar researchers have previously discovered dozens of sinkholes in Shaanxi province, northwest China, and a cluster of interconnected sinkholes in Guangxi, China Daily report.
Originally published on Live Science.
https://www.livescience.com/new-sinkhole-discovered-china Giant sinkhole with a forest inside found in China