Ancient forest discovered inside giant sinkhole in China

Lixin Chen and her team descend into the abyss. (Hongying Wu/Atlas Obscura)

Residents of Leye County in southern China’s Guangxi Zhuang Autonomous Region are no strangers to sinkholes. The 29 of the region majestic underground chasms and caves have earned themselves a UNESCO World Heritage Site designation. But the one explored by scientists in early May 2022 hosted a extraordinary secret – a well-preserved ancient forest.

Lixin Chen, founder of Guangxi 702 Cave Expedition Club, and his team first descended inside the massif chasm on May 6, 2022. It didn’t take long for them to reach solidify ground to walk. But the group soon realized that they were nowhere near the bottom of the 630-foot-deep chasm. They should to cross through dense undergrowth lush green vines and trees up to 130 feet for a few hours to get there.

Chen and his team had to trek through the dense forest to reach the lowest point of the chasm. (Credit: Hanshun Gong/Atlas Obscura)

Chen told Atlas Obscura that the environment reminded him of a scene from the movie Avatar. “The vines of the trees entangle us like cobwebs, and you have no idea how deep your next step will be,” he says. “The plants were so brittle that you could knock them down with your hands, but they would recover just as quickly. When we came back [up]the path was hidden again.”

Scientists have since returned to the sinkhole which they have repeatedly named “The Eagle”. They found three collapsed caves, evidence of an ancient underground river and a small underground lake. Chen said, “I wouldn’t be surprised to know that there are species found in these caves that have never been reported or described by science until now.”

An underground lake inside the Eagle. (Lixin Chen/Atlas Obscura)

Tiankeng, or “heavenly pit”, the Mandarin name for these huge sinkholes, is a common feature of karst ground. Mainly natural landscapes to understand carbonate rocks like limestone and dolomite. When rainwater falls on rocks, a chemical reaction causes small cracks and tunnels to form in the rock structure. Over time, these cracks widen due to erosion and ultimately collapse in on themselves, opening sinkholes or giant caves.

The chasms, left untouched by man activity, maybe a oasis for life, especially for strangers species. Massive sinkholes are also a leads underground water reservoirs or aquifers. Karst aquifers are the main source of water for more than 700 million people around the world.

Resources: Smithsonianmag.com, Livescience.com, Unesco.org