China: Scients find 192m-deep sinkhole with ‘well-preserved primitive forest’

Cave explorers in China stumbled upon a massive sinkhole with a hidden forest inside in south China’s Guangxi region.
At its bottom, scients found trees as tall as 40 metres — for comparison, coconut trees are usually around 20 to 30 metres tall — and the ground covered dense plants, reported China’s state media Xinhua.
With this, the number of such sinkholes in Leye County has reached 30. However, what sets this sinkhole apart is its size — it measures 306 m (1,003 ft) in length, 150 m (492 ft) in width and 192 m (629 ft) in depth. Its volume exceeds 5 million cubic meters.
Quoting Zhang Yuanhai, senior engineer at the Institute of Karst Geology of China Geological Survey, the Chinese media house said the structure has three caves in its walls and a “well-preserved primitive forest” at its bottom.
The ancient trees growing at the bottom are nearly 40 meters high, and the dense shade plants are up to one’s shoulders, leader of the Guangxi 702 cave expedition team Chen Lixin told Xinhua.
As per reports, a team of scients rappelled over 100 metres into the sinkhole and trekked hours to get to its bottom. They wound up the exploration on May 6 and returned to safety.
The US Geological Survey website defines a sinkhole as a “depression in the ground that has no natural external surface drainage.” They are typically found in “karst terrain” where the rocks below the land surface are soluble in groundwater.

A team of Chinese scients has discovered a giant karst sinkhole, with an ancient forest inside, multiple media outlets have reported. Located in south China’s Guangxi Zhuang Autonomous Region, the pit is 192 meters deep & is home to ancient trees, up to 40 meters tall! pic.twitter.com/P6mbN16kwt
— DW Global Ideas & Environment (@dw_environment) May 18, 2022
Apart from China, Mexico, Papua New Guinea, and parts of the US have reported occurrences of sinkholes.