A group of Chinese, British and American scientists have discovered what they described as rarely seen clusters of water-eroded caves and underground rivers in the Guangxi Zhuang Autonomous Region, south China.

Located within 50 square km around Lihu, the caves and the underground rivers, numbering several hundred, were discovered by seven experts during their expedition in Lihu township in Nandan County of the region.

The experts, including Zhu Xuewen, president of the China Society for the Study of Speleology, and Han Daoshan, associate professor with the Chinese Academy of Geology, took field inspections of three larger caves.

The No.1 cave they investigated is 2,968 meters long with a lot of unique pearl-shaped, ball-shaped and cake-shaped stone formations.

Stone pearls of one to 100 mm in diameter were found in every large hall-like part of the No.1 hole.

Stone pearls have developed the similar way the real pearls did when calcium carbonate gathers on a certain core in karst area.

Zhu Xuewen, also a professor with the Institute of Karst Geology, said the stone pearls are about 15 centimeters thick in the largest hall, which covers an area of 600 square meters.

The caves and the underground rivers are the largest and rarest in China in terms of size and number, and some experts believe they are also the biggest in the world.

The group also surveyed two large underground rivers. One river, named Ganhe, is 3.5 km long, with the widest river bed being 50 meters and the deepest section being 60 meters.

The other underground river, the Balao, is 3.2 km, running in a zigzag course.

"The biggest cave in a hill is almost as high as the hill itself with stalagmites and stalactites in all forms. Yet the hills are covered with lush vegetation's, including shrubs and grass, where musk deer and monkeys can be seen from time to time."

Located in the marginal area linking the Guangxi Basin and Yunnan-Guizhou Plateau, the karst caves around the Lihu are typical subtropical karst landforms, said professor Zhu.

The professor said the typical land formation featured by well- grown vegetation, karst caves and underground rivers is of great value for scientific expeditions and tourism development.

The Lihu township, which is famous for its well-protected primitive local customs, is 26 km from the Nandan county town in the northwest part of Guangxi.

(People's Daily 07/08/2001)