Yunnan 2003 Expedition Initial report
14th July to 24th August 2003
"Somewhere in the mountains west of Zhongdian"
Hong Meigui Yunnan 2003 was a 5-week caving expedition to the mountain range that lies to the west of Zhongdian town, in the north of Yunnan Province, China. At the start of the expedition we had knowledge of one large resurgence cave (C3-1) found, but left unexplored, in 2002, and several tens of square kilometres of mountain to check out...
The expedition benefitted greatly from the help and information of the local Tibetans. Up on the tops, by far the most efficient method of cave-hunting was to ask the local yak farmers to show us the entrances they had come across during their work. In this respect the timing of our expedition was very fortunate: unbeknownst to us during the expedition planning phase, these farmers live in the mountains only during the months of June, July and August, and were just leaving as our expedition drew to a close.
Resurgence exploration (C3-1)
The resurgence project was quickly knocked off. After 200m of easy dry walking passage, the fossil passage rejoined the main streamway, and dangerous water conditions prevented further exploration at this time of year. However, locals report that (a) 1.5 km of electric cable has been laid in the cave (giving us some idea of the length of explored cave), and (b) they have explored the cave only during the dry season, when water levels are much lower. Rich Gerrish and Duncan Collis plan a return expedition to explore this cave (with others) in January-February 2004.
Those with more competence than the 2002 cowboys estimate the water flow from this cave (at this time of year) at 4m3s-1. Two other resurgences were found nearby, one estimated at 2 m3s-1, the other (an underwater resurgence in the bank of the Yangtze) of unknown flow rate.
The expedition focussed almost exclusively on the southerly part of the mountain range - further south than any exploration carried out during the Yunnan 2002 trip. Several daytrips and many short camps at various locations carried out assessments of the potential, and began the search for entrances.
The southerly areas look more promising than the peaks and plateaus explored during 2002 - entrances seem easier to come by, although still not growing on trees. 57 new entrances were logged during this expedition, most at altitudes in excess of 4000m. Two dropped to depths of approximately 75m before choking (in one case) or becoming too tight (in the other). Many remain unentered and several are promising prospects. In particular we are excited about:
C3-67: a 10m wide, 10m high steeply descending passage with a slight but noticeable draught, leading to a ~20m pitch which has not been descended. (altitude approx. 4250m)
C3-81: a small entrance in an uninspiring outcrop leads to 100m of walking sized active stream passage, and eventually to a 5m pitch which has not been descended. A prime candidate for a dye trace. (altitude approx. 3900m)
The Yunnan project is still young, but the 2003 expedition has strengthened its members' hope that somewhere in the mountains west of Zhongdian lies an extremely deep cave system, perhaps in excess of 2000m depth, and that eventually we will find our way into it. Plans for Yunnan 2004 are under way. The full Yunnan 2003 report will follow shortly (hopefully!).