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Road and cave entrance by the Wu Jiang near Wulong
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1996 Yangtze Gorges Expedition
Wulong Area
Introduction
by Jack Sheldon
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| Four members of the team carried out a three day recce to the area above Wulong and centred on the village of Qing Sui at 29º26'15"N 107º40'22"E. In that time the group surveyed three major caves, examined numerous lesser sites between Qing Sui and the villages of Mu Geng at 29º31'12"N 107º39'08"E and Meizse at 29º31'26"N 107º42'02"E, and also briefly visited the area around the "Fairy Mountain" holiday centre, approximately 90 mins drive above Qing Sui.
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The Wu Jiang flows to the Yangtze River (Chang Jiang) at Fuling
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The most impressive feature was undoubtedly Long Lao Dong and the large associated resurgence. Here, ten minutes walk from Qing Sui, water is forced up under pressure where the Permian limestone meets a major band of Silurian shale. Under normal flow, approximately 3 cumecs emerge from the spring, with a further 1 cumec emerging from the impressively large but short (250m) Long Lao Dong. The cave clearly has an 'overflow' role, and must carry far greater quantities of water in flood. This valuable source of water, almost 1000m vertically above Wulong is canalised and used lower down to generate hydroelectricity. 30 m above the current resurgence level is a large fossil cave, which is approached via a narrow ledge, contains much evidence of human occupation and was clearly used as a place of refuge during troubled periods in the country's history. |
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It is quite clear that this area must contain a large drainage system, but it may not be readily accessible. During the visit to Mu Geng, the team examined the major sink of Long Sui Dong at 29º27'51"N 107º40'38"E. |
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This sink is developed at the junction of the Triassic and Permian limestone. Unfortunately after dropping down a couple of short free-climbable pitches the cave ends immediately in a large round sump pool. From this point, Long Lao Dong is 10.3 km distant on a bearing of 174º. Other caves, both fossil and active, are said to be located near Long Sui Dong, but lack of time precluded closer examination.
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Many new bridges and roads were being built across and along the deep gorges.
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The brief visit up to Fairy Mountain was quite revealing. Local opinion was that it was not cave bearing, but this was partially contradicted by the evidence. Despite being short on time and having little chance to move far from the vehicle, large numbers of dolines were seen, including one that was approximately 400 x 250 x100m filled with dense vegetation and which featured a small cave set back in one wall (and possibly others had time permitted a full examination). The whole Fairy Mountain area was covered in smaller surface depressions, and a couple of days spent there could well prove rewarding. It certainly has considerable depth potential.
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Anne Gallagher and the rest of the team find it warm work searching for cave entrances.
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The longest caves surveyed in this area were Chiao Zhe Dong (2km) and Xia Dong (1km). Both were ancient abandoned phreatic resurgence caves of large dimensions, and Xia Dong was intersected by a much more recent, relatively immature vadose system which was partially explored. Further evidence of this modern drainage and the complex local geology is to be found at numerous sites where small springs resurge from impenetrable beddings and cracks at the junction of limestone and shale.
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