Chapter 10: TYPES OF KARST SYSTEMS

Résumé -Abstract - Zusammenfassung -:There are two kinds of karst systems in South China: tunnel-caves with an exclusively allochthonous catchment area (e.g. Gebihe, Ziyun/Guizhou) and cave systems in folded geological structures with an autochthonous catchment area (e.g. the synclinal system of Wuxi in Sichuan or the system of Santang in Zhijin, Guizhou). An example of the mixed type combining tunnel-cave and autochthonous underground system is the cave system of Longdong, which developed along a large anticlinal block at Wufeng in Hubei.
 The tunnel-caves of South China are the most numerous and voluminous of this planet. Many subterranean canyons surpass 100 m in height (120 to 150 m at Gebihe). The deepest known pit is the P370 of Gebihe and the most important shaft is the 320 m deep entrance shaft of Fengdong (Bama / Guangxi). The big room at Gebihe (Ziyun / Guizhou), called Chamber of the Miaos, measures 700 x 200 x 70 m and is the second largest known in the world. The height of vaults in other chambers surpasses 100 m and the height of a talus hill in Longdong (Wufeng / Hubei) reaches 110 m. In the cave system of Pan Yang (Bama / Guangxi), which has been explored by an Anglo-Chinese expedition, the famous "Cloud Chamber" can be found with its cloud of fog resulting from warm air trapped under the vault.
 The genesis of the large underground features is directly related to the impressive discharge of the allochthonous rivers passing through the tunnel-caves. The  giant pits are due to the collapse of large underground chambers or galleries. In the remnant stumps of tunnel-caves passage levels are spread across a vertical distance of several hundred metres and have developed in the course of the strong uplifts during Neogene and Quaternary (see chapter 11).

Keywords: Karst system, tunnel-cave, synclinal system, allochthonous river, autochthonous catchment area, pit, shaft, chamber, gallery, breakdown, dissolution, mechanical erosion, base level,  passage level, uplift, tectonic, lithology, Santang, Gebihe, Longdong, Wuxi, Guizhou, Hubei, Guangxi, Sichuan.