Map of Pha Soung Mountain karst, Laos.
The Speleological Club “Z” from Nuremberg, Germany, started speleological research in Laos in 2006. Since 2015, the research moved to another qualitative level and it organised 6 international expeditions. The expeditions have worked only in the provinces of central Laos: Khammouane and Bolikhamsay. Bolikhamsay Province was a secondary field of activity, the longest surveyed cave was Tham Nang Pha Hong (215.3 m). Instead, the most searched province was Khammouane. In the area of Gnomalat City the most important caves surveyed were Tham Lod (1,310 m) and Tham Lom Yen (1,057 m); in the last cave, explorations will continue next year, 2020. The most intensive researches started in 2010 in the upper basin of the river Nam Don, in the area of Ban Na and Ban Phondou villages. Near the last village, we explored and surveyed two caves exceeding 2 km long, Tham Dan Makhia (2,093 m length) and Tham Houay Sai (2,043 m length); the last one discovered this year, 2019. Tham Houay Sai is a unique and large gallery, which ends into a huge hall and a final sump. The research in both caves will go on. The base for all expeditions was the village of Ban Na. To the west of the Nam Don river is an isolated mountain, Pha Soung, meaning in translation: “The mountain that touches the sky“. So far no one climbed it. At the base of mountain, in 2009, it knew 5 caves (searched by one British and other two French teams), of which the longest measures 1,827 m. In 2015, the Speleological Club “Z” searched again this mountain, already abandoned by speleologists, and managed spectacular junctions. So, it resulted the great cave system Pha Soung, with a development of 21,012 m. Also, in the same mountain, it discovered, explored and surveyed other 20 caves. Three of them are interesting: Tham Kammatan, a huge tunnel completed by a large maze (total length: 2,106 m), Tham Nam Kouan Moo Yo (an extreme maze, with very low galleries, total length: 1,705 m) and Tham Pha Kouan Moo (total length: 1,055 m). Unfortunately, these spectacular caves could not join the Pha Soung system. The Pha Soung system is not only the third cave in Laos, but it is by far the most labyrinthine network. On only 1,100-m-distance it developed 21 km of galleries. The cave has 70 entrances! The cave network results from the river Nam Don, which during the monsoon season floods the cavity and fills a closed polje, Kouan Moo. Pha Soung System is a typical deep-phreatique cave, with fantastic forms of corrosion. We discovered in 2018 in Pha Soung System one palaeontological deposit with petrified bones, and in Tham Pha Kouan Moo, 16 golden statues of Budha, dating from the 16th century. In 4 years, our club discovered in Laos 44 caves, which totaled 37 km of surveyed galleries.
Author: Liviu Vălenaş
Section: Cave explorations and expeditions
Type: Oral presentation
About author:
Liviu Vălenaş born in Brașov, România, on February 2, 1951. In 1975, he finished the faculty of geography at the Babes-Bolyai University of Cluj, Romania, with a diploma in karst geomorphology. Between 1978 and 1979 he specialized in geomorphology and geochemistry of karst at the Silesian University in Katowice, Poland. Soon after ending of faculty, Muzeul Tarii Crisurilor in Oradea City, Romania – one of the largest museums in România, employed him as a professional speleologist. In 1979, UIS – International Union of Speleology elected him to the commission of geochemistry and hydrogeology of the karst. He started the speleology as a child in 1959. In 1973, Liviu Vălenaş founded the speleological club “Z” in Oradea City. In Romania he discovered near 800 caves, the largest caves being the Humpleu Cave, 36.2 km; Hodobana Cave, 22.2 km (the most labyrinthine limestone cave in Europe); Zapodie System, 12.2 km, and so on. Liviu Vălenaş surveyed 120 km of galleries in various caves of Romania. After the fall of communism, he settled in Federal Germany. There, he reorganized the Speleological Club “Z” and reoriented exclusively to Indochina: Thailand and Laos. In Laos the most important achievement is Pha Soung System (21,012 m total length /2018). 100 specialized articles and 4 books on the geomorphology of the endocarst materialized his scientific activity. Beginning 2016 he is editing the magazine “Caietele Clubului de Speologie “Z“, reaching actually the number 14.
Pha Soung System, Laos. Photo by Liviu Valenas.
Pha Soung System, Entrance no 1, Laos. Photo by Liviu Valenas.
