Chapter 2: CAVES OF HEFENG COUNTY (HUBEI).

Résumé - Abstract - Zusammenfassung : In the SW corner of Hubei the hilly county of Hefeng is situated in the neighbourhood of Wufeng county and culminates at 2326 m. It is a SW-NE folded area of Permian and Triassic limestones. The type of the karst landform is qiufeng-uvala with poljes and canyons. The humid subtropical climate (1737 mm/year, 15.5 °C at Hefeng, 520 m a.s.l.) has a pluviometric amplitude marked by winter minima of 27 mm in January and summer maxim of 314 mm in July. In 1989, during a three day reconnaissance 3.3 km were surveyed in seven caves. During the 1992 expedition, another 30 caves were mapped to an accumulated length of 30 km. These caves are associated with three distinct hydrogeological systems. Two of them (Taiping and Yanziping) are aligned with the Hefeng syncline and are located to both sides of Loushuihe river. The Yanziping system on the NE side, is fed by sinkholes probably resurging at the Wanrendong emergence-cave. On the SW side, the Taiping system drains a large polje (Cedong ponor and cave). Located at the outlet of Loushuihe valley, the Yinquandong emergence-cave (1,3 km), resurgence of the system, is a fine example of an underground delta in stepped levels. The third system (Shuishanping) is enclosed in a limestone monocline, trapped by shales.

Key-words: Limestone, Permian, Trias, qiufeng, uvala, polje, ponor, underground delta, cave levels, resurgence, canyon, climate, hydrogeological system, Hefeng, Hubei.