地下裂縫

Dìxià lièfèng - Underground Crack

Useful Information

Location:	Shuanghe Village, Wenquan Town, Suiyang County, Zunyi City. (28.2416968, 107.3000832)
Open:	All year daily 8:30-17. [2023]
Fee:	Adults CNY 120. [2023]
Classification:	Karst cave
Light:	Incandescent Electric Light System Coloured Light
Dimension:	L=400,759 m, VR=912 m, T=15 °C.
Guided tours:	D=1.5 h, L=1,000 m.
Photography:	allowed
Accessibility:	no
Bibliography:
Address:	Dixia Liefeng.
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then. Please check rates and details directly with the companies in question if you need more recent info.

History

1987	beginning of speleological exploration.
MAR-2018	the cave reaches 238 km in length and becomes the longest cave in Asia.
MAY-2023	the cave reaches 400 km in length and becomes the third-longest cave system in the world.

Description

地下裂縫 (Dìxià lièfèng, Underground Crack) is the name of a show cave which is located at the 池武溪 (Chiwuxi river), about 4 km downstream from the resurgence and show cave 双河水洞 (Shuāng héshuǐ dòng, Shuanghe Water Cave). Most caves in the area, like both show caves, are actually part of a huge 400 km long caves system named Shuanghedong Cave System. 响水洞 (Xiangshui Dong) is the entrance and 大风洞 (Dafeng Cave) is the exit of this show cave tour. Underground Crack is a funny but unscientific name, but actually the cave is very high but narrow, at the narrowest point it can only be passed by one person sideways. The fact that the two entrances have different names ist simple, the people named all the entrances but were too fearful or lazy to actually explore the caves behind. So each entrance got its own name, until it was finally connected to the main cave system, in this case Shuanghedong Cave Network (双河洞, shuānghédòng, Twin Rivers Cave). The official text goes like this:

The cave is named after the longest underground crack ever discovered in China. The crack gradually widens from top to bottom. At its narrowest point, only one person can pass sideways, and the total length is 1,000 meters.

What a load of bullshit, definitely as weird as "127 different kinds of stalagmites", "it is a natural oxygen bar with a high content of negative oxygen ions", and "there are holes and holes in the holes". We actually have no idea what they are talking about and assume that it is some kind of Chinese saying. There is no such thing as an "underground crack", it's just a narrow and straight passage. Any karst cave forms along a crack. The total length of this passage is 400 m, the 1,000 m are the total length of the tour, and it was definitely not intended that readers mix this up. And no, negative oxygen ions do not exist, that's just esoteric babbling.

One of the highlights of the tour is the 地心之门 (Dì xīn zhī mén, Gate to the center of the earth) or 無底洞 (Wúdǐdòng, Bottomless Pit). This is a vertical shaft which goes down to the lowest level with the cave river. In other words, at the end of the short detour there is a possibility to see a vertical shaft going down. Ignore all comments about "it is not yet clear how deep and long it is", which is obvious nonsense, as this part of the cave was surveyed before the show cave was opened. Or "cave explorers have determined that it leads to Chongqing and Tongzi County in Guizhou Province", which is obviously the local version of the Smile Far Connection Legend, which seems to be a general human weakness. However, in this case, the cave system extends actually across two districts, and so any point of the cave is connected to the whole system, that's a nobrainer. And the "caving experts explored the cave for 13 days, but in the end had to retreat due to supply reasons" is also nonsense. Any cave expedition is organized that way, you plan with return in mind, and when the planned time is reached you return and come back next year. That's simply how this is done all the time for security reason. It's not a notable exception, and the text is simply intended to raise mystery where no mystery is.

Notable is the 千人大廳 (Qiān rén dàtīng, Thousand People Hall), which is big enough—you guessed it—for 1,000 people. It is used for cave events, like the Cave Poetry Event in 2015 or various cave concerts.

The cave also has rocks, which are a little exceptional, and the Chinese value them highly because they are very decorative in their gardens. It is called 太湖石 (Taihushi, Lake Taihu Stone) in China, because the most famous specimens originate from Lake Taihu. Actually, it is quite common, its simply how dolomite weathers: it gets a lot of holes. Dolomite consists of a combination of limestone which is CaCO₃ and MgCO₃, where the Ca atom is replaced by the Mg atom, which has similar properties. The resulting rock is called dolomite or dolostone and has the formula CaMg(CO₃)₂. This formula actually omits an important fact: dolomite is formed by the replacement of Calcium by Magnesium during early diagenesis, and this process is incomplete. The relation between the two elements changes continually, and so do the physical properties and the resistance against weathering. That's the reason why some spots weather fast and produce holes in the surrounding rock which weathers slower.

The show cave is a part of the Shuanghedong Cave System (双河洞, shuānghédòng, Twin Rivers Cave), which has become the third-longest cave system on Earth lately [2023]. And it was the longest cave of Asia for several years before [2018]. The whole system contains numerous waterfalls, four major tiankeng, and at least three underground rivers fed by numerous losses and the aquifer. The cave has three major levels, the lowest is the active cave with the cave rivers and resurgences. It has 105 entrances and extends mainly over the district of Suiyang, but also over that of Zheng'an with its northern part. It also has spectacular troglobionts, like tadpoles, frogs, salamanders, insects, spiders, bats, leeches, cave shrimp, and blind fish weighing several pounds. The cave is located in Lower Ordovician and Middle-Upper Cambrian (541 to 443 Ma) dolomitic limestones and lodestones. There are also some layers of gypsum, so there are gypsum caves and gypsum minerals in the limestone caves. The area of the cave system is part of the 双河洞国家地质公园 (Shuāng hé dòng guójiā dìzhí gōngyuán, Shuanghedong National Geopark), which has an area of 318 km². For unknown reasons, the scenic area which manages the caves is named 十二背後 (Behind the Twelve).