Tham Doun Mai

DREYBRODT JOERG informations

Frédéric Urien - 23/06/2024

History: Explo history: --- 22-25.01.2012: explored by the Northern Lao-Europea Cave Project 2012, surveyed to 455m -- 02.-07.01.2013: explored by the Northern Lao-Europea Cave Project 2013, 1.655m survey added, +/- finished Cave description: Situated upriver from Muong Ngoi, on the western bank. The entrance is reached by a 15 min walk uphill along narrow paths. The entrance is a small hole, approximately 1,5 x2m, at the foot of a rock face, which is climbed down into a large passage. It is accompanied in parts by a parallel passage and is blocked in the end by stal. A short crawl is passing under the stal into a very large hall with large breakdown blocks and large sinter formations. To the right a passage with dry gourpools is going on, it ends with a 26m drop down to the underlying river passage. A hole in the floor shortly before the end of the passage, with conveniently placed stalagmites offers an easier rigging option for the descent to the river passage. Downriver, the passage sumps after 300m. Upriver, the passage is first easy walking in a shallow river with gravel ground, then the water gets deeper and some stal blocks the passage, leaving about 20cm of airspace. The passage behind becomes narrow, with sharply eroded limestone and the river more of the character of a mountain torrent. The river passage becomes inpassable and is bypassed by climbing up the rock towards the right, greatly aided by a rope urs has installed, and descending by rope again further up the passage. Another deep section with airspace limited by stal, then the passage widens again. A large series of active gour pools draws down from the left. (river passage on: Nancy & Matt). On top of the gour pools, a passage with clay ground leads to an balcony above the river on the right, and another passage to the left. Here are meanders of standing water with a muddy, stinking bottom, which have to be crossed several times. The water becomes finally clear, the clay and mud is replaced by rock and stal, some gour pools are to the left. The water course becomes a deep canyon with beautiful sinter formations, the walls black from manganese, and the horizontal parts densely covered with drip holes. Finally more large gour pools, which can be passed by, the water is draining downward behind it, judged by the roar in direction of the river, a stal almost blocks the passage, on can just squeeze by, a further 20m on all the water vanishes in a sloping crack, the passage ends here. In the upper parts of the cave, some spiders and crickets, two rats and a single bat were seen, generally there was little fauna. In the river, shrimps were seen, but too fast to be caught. The others have seen white fishes, but they were absent when I was there. In the side passage, white millipedes, white collembola and a large brown huntsman spider were seen. Citation: Analysis: [update]: A 15-minute trail lead to an inspicious entrance, Tham Doun Mai. We downclimbed it into a larger passage, which was blocked by a large stal at the end, A flatbelly crawl under the stal lead into a very large hall, with breakdown blocks, large columes and beautiful decorations, A passage with large dry gour pools ended at a drop 25m down into a river, and just as high at the balcony where we were standing. A hole just before the end was rigged, our two Suisse, Urs and Manu went down, the rest started surveying in two teams. We just finished the upper parts, the descending team reported the river passage as going, The shaft we descended is a 1,5 x 2m-hole with a big stal to fix the rope, which widenes into a 10m-river passage. the first part is easy going in kneedeep river and gravel banks, then the water becomes deeper, and the river is overhung by stal. At two places the airspace is just 20 cm, which forces you to put your head under water. Luckily our caving lights are watertight... Further on the passage becomes narrow, sharply erroded limestone, the river more like a mountain torrent, and we more climbing than wading. Finally, no more passage at water level, we climb up, greatly helped by the rope Urs has installed (I don't even want to know how he got up there without), abd abseil down on the other side, more deep water with a duck, then we have reached the place where last days survey stopped. Matt and Nancy will go on following the river, Urs, David and me survey up a series of amazing gour pools, and than follow a side passage. Stagnant water and deep mud first, which smells rotten when you had to cross it, which we did several times, Then the passsage became rocky, with phantastic formations, clear water partly in steepsided canyons. We were climbing again above the water, in parts the rock was coated black and smooth with manganese, sometimes decorated with creme-colored stal, bizarre erosion forms from dripping water, a surreal landscape. Finally the passage is blocked by stal, you can just squeeze beside it, another 20m passage, then the water vanishes in a steeply slanting gap, from the gushing sound I guess down to the river. This is the end of our survey. We head back, meet the others, who have turned around in open passage, but this will remain for another expedition. [diary]: So 22.1.2012: [...] flußauf gefahren, an Muong Ngoi vorbei, dann irgendwann am Westufer angelegt, 15 min den Berg hochgelaufen, kleiner Eingang, dahinter ein großer Gang, mit Parallelgang, Kriechstrecke durch eine Tropfsteinblockade, dahinter ein Riesenraum. Schöne Tropfsteine, ein Gang mit gourpools, am Ende dann ein Schachtabstieg zu einem Fluß. Die Höhle heißt Tham Doun Mai, Pos. Nancy N 20° 45,453’ E 102° 38,862’ 352m Alt. Jörg, Aileen und ich vermessen vom Eingang her, Nancy & David vom Crawl weg, Matt fotografiert, Urs und Manu steigen zum Fluß ab, geht in beide Richtungen weiter. Hab 2 Spinnen gefangen, paar Crickets, sonst wenig Leben. Eine einzige Fledermaus gesehen. [...] Di 24.01.2012 [...] Positions: Ban Sop Jam N 20,77772° E 102,64999° 343m, Tham Han (= Tham Viet) N 20,77653° E 102,65344° 349m, Tham Doun N 20° 75538° E 102,65111° 343m, 2: N 20° 75535° E 102,65109° 341m [...] an der alten Stelle zur Tham Doun Mai angelegt, zur Höhle hochgelaufen, 2 Teams wollten zum Fluß abseilen und flußauf und flupab vermessen. Mit den Guides reingegangen, zwei Ratten gesehen. ‚hab Manu meinen Gurt & Neopren dagelassen, dann sind David, Aileen, Tien & ich weitergefahren, [...] Die anderen an der Höhle aufgelesen, flußab nach 300m Syphon, flußauf geht die Höhle.[...] Mi 25.01.2012: [...] zur Höhle gefahren, Manu, Tien & Aileen wollen draussen nach neuen Eingängen suchen, der Rest hat Neopren angezogen und den Schacht abgeseilt. Haben im Fluß Shrimps gesehen, waren aber zu schnell, soll weisse Fische geben, aber keine gesehen. Den Fluß hoch, erst Kiesbett, dann unter ein paar Tropfsteinen durch, vielleicht 20cm Luft, paarmal schwimmen, dann wurde alles schmal, stark erodiert, scharfkantig, bei einer Kletterstelle verzweifelt, schließlich zurück und ins Wasser, Urs kam zurück, um zu schauen, wo ich bleibe. Schließlich nochmal ein knapper Luftraum unterm Tropfstein, davor eine Kletterstelle, in der das seil eingebaut war. Gurtzeug wieder angelegt, schliesslich kam eine große Serie von Sinterbecken, ab hier Neuland. Nancy & Matt sind weiter den Fluss entlang, wir die Becken hoch nach oben vermessen, nach rechts gehts auf einen balkon über den Fluß hinauf, nach links Lehm, ein Wasserlauf, allerdings stehendes Wasser, Schlammboden, stinkt, mussten trotzdem 3-4 mal durch. An einem Tropfstein Flutdebris, ein weisser Milliped und ein paar kleine weisse Collembolen oder sowas, natürlich mein Sammelzeug unten am Fluss gelassen, ärgerlich! Dann noch eine große Spinne gesehen, Heteropoda, ungemustert, keine Chance mitzunehmen. Das Wasser wurde schliesslich klar, Sinterbecken, tiefer Canyon, wunderschöne Tropfsteinsäulen, Stalagmiten uä. Wände schwarz mit Mangan überzogen, in den horizontalen teilen dicht an dicht Tropflöcher, schliesslich nochmal große Sinterbecken, man konnte daran vorbei, dahinter geht das Wasser nach unten ab, dem Rauschen nach Richtung Fluss, an dem Tropfstein kommt man noch vorbei, vielleicht nochmal 20m weiter, dann ging das Wasser entgültig nach unten in eine schräge Spalte zum Fluß, Passage zu ende... Umgedreht, zurück, Nancy 6 Matt waren auch schon da, ihre Passage geht weiter. Rückmarsch [9696]: Januar/Februar 2012 zwei unabhängige Expeditionen [...] Provinzen Luang Namtha (Vieg Phoukha-District) sowie Luang Prabang (Nong Khiaw- und Muang Ngoi-District). Dabei wurden 19 Höhlen mit rund 3,5 km Gangstrecken gefunden, darunter die Tham Doun Mai bei Muang Ngoi. Die Höhle hat eine reich mit Tropfsteinen und Sinterbecken geschmückte inaktive Etage sowie einen langen unterirdischen Flusslauf, den man über einen 20 m tiefen Schacht erreicht. Die vermessene Länge beträgt rund 2,1km [9583]: fauna record [synopsis 2013]: 1
F48-110
F48-110-020
02.-07.1.2013
Tham Doun Mai
N 20o45'27.2''; E 102o38'51.7''
352
Ban Sop Jam
Muang Ngoi
Luang Prabang
1.655
JD+AM
JD+AM
+/- finished; Comment Michael Laumanns: only additions to 2012. Total: 3,745 m [10090]: fauna record [10286]: nn, short description, Survey ([Wang et al. 2019): Study site and climatology: Tham Doun Mai Cave (TM cave; 20° 45' N, 102° 39' E) is a 3,745 m-long cave located at 352 m above sea level in Luang Prabang Province, Laos Equipment: Remarks: References: [9696]: Krause, M. & Laumanns, M. (eds.) 2012: Forschung Aktuell: Laos. - Mitteilungen des Verbandes der deutschen Höhlen- und Karstforscher 58 (1): 27. [9583]: Jäger, P. 2012: Revision of the genus Sinopoda Jäger, 1999 in Laos with discovery of the first eyeless huntsman spider species (Sparassidae: Heteropodinae). - Zootaxa 3415: 37-57. [10090]: Steiner, H. 2013: Biospeleological Research in the Lao P.D.R: - Pp. 413-419 in: Filippi M., Bosák P. (Eds), 2013. Proceedings of the 16th International Congress of Speleology, July 21- 28, Brno. Volume 1, p. 453. Czech Speleological Society. Praha. [10258]: Dreybrodt, J. & Laumanns, M. (eds.) 2013: The unknown North of Laos (Part 5 - 2012-2013: Karst and Caves of the Provinces Luang Nam Tha, Luang Prabang and Houaphan). - Berliner Höhlenkundliche Berichte 49. 110 pp + Appendix. [10286]: Pistole, N. & Oliphant, M. 2014: River Caves and Through-trips in Northern Laos. - NSS News, February 2014: 12-17. -- Wang, J. K.; Johnson, K.R.; Borsato, A.; Amaya, D.J.; Griffiths, M.L.; Henderson, G.M.; Frisia, S.; Mason, A. 2019: Hydroclimatic variability in Southeast Asia over the past two millennia. Earth and Planetary Science Letters 525: 115737.