Giant karst sinkholes discovered in S China

Member of a cave exploration team prepares to investigate a giant karst sinkhole called "Xiaonongkun Tiankeng 2" in Donglan County, south China's Guangxi Zhuang Autonomous Region, Nov. 26, 2019. A cave exploration team has discovered two giant karst sinkholes, and over a dozen smaller limestone caves in the mountainous county after a week of expedition. The 30-membered team, which consisted of speleologists and cavers from China, France and Belgium, went through field measurements and found one of the two giant sinkholes, measuring over 300m in depth, 250m in width and 120m in length at the bottom, is one of the world's 50 largest karst sinkholes. (Photo by Chen Lixin)