Shaanxi tiankeng cluster is a group of 19

karst Karst is a topography formed from the dissolution of soluble rocks such as limestone, Dolomite (rock), dolomite, and gypsum. It is characterized by underground drainage systems with sinkholes and caves. It has also been documented for more weathe ...

sinkhole A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are locally also known as ''vrtače'' and shakeholes, and to openi ...

s in

Shaanxi Shaanxi (alternatively Shensi, see § Name) is a landlocked province of China. Officially part of Northwest China, it borders the province-level divisions of Shanxi (NE, E), Henan (E), Hubei (SE), Chongqing (S), Sichuan (SW), Gansu (W), N ...

Province, China. The discovery was made in February 2016 and announced by geologists on November 24, 2016.Hong'e, Mo (2016-11-25)
"Giant karst sinkhole cluster discovered in NW China"
Ecns.cn. Located within a 200 km-long karst landform belt in the southwest part of the province near

Hanzhong Hanzhong (; abbreviation: Han) is a prefecture-level city in the southwest of Shaanxi province, China, bordering the provinces of Sichuan to the south and Gansu to the west. The founder of the Han dynasty, Liu Bang, was once enfeoffed as ...

City, the cluster is one of the largest on Earth. It includes forty-nine sinkholes and more than fifty funnels ranging from 50–100 metres in diameter. The area is in the Qinling-Bashan Mountains, spread over Hanzhong city's counties of Ningqiang,

Nanzheng Nanzheng District (), formerly Nanzheng County (), is a district of the city of Hanzhong Hanzhong (; abbreviation: Han) is a prefecture-level city in the southwest of Shaanxi province, China, bordering the provinces of Sichuan to the south ...

, Xixiang and

Zhenba Zhenba County () is a county under the administration and in the southeast corner of Hanzhong City, in the southwest of Shaanxi province, China. The southernmost county-level division of Hanzhong, it borders Sichuan province to the south. Admin ...

. It is the northernmost example of the humid tropical and subtropical karst landform area, lying roughly between the latitudes of 32 and 33 degrees. From October 25 to 28, 2016, a team surveyed the region. The team was made up of China's resource authorities as well as experts from the

UNESCO The United Nations Educational, Scientific and Cultural Organization is a List of specialized agencies of the United Nations, specialized agency of the United Nations (UN) aimed at promoting world peace and security through international coope ...

International Research Center on Karst, the International Union of Speleology, as well as other research bodies of the Czech Republic ( the Czech Speleological Society and the Institute of Geology of the Czech Academy of Sciences), China ( the Institute of Karst Geology of the Chinese Academy of Sciences), and France. Among these new sinkholes is one that is over 500 metres in diameter. Seventeen are 300–500 metres, and 31 are over 100 metres in diameter and equally deep. Prior to this discovery, only 130 such sinkholes were known in the world, 90 of which are in China.

References

{{coord missing, Shaanxi Karst formations of China Landforms of Shaanxi Sinkholes of Asia