| Kapitel | Titel | Seite |
|---|---|---|
| Abstract / Zusammenfassung / Résumé | 5 | |
| 1 | Acknowledgements / Team Meübers | 6 |
| 2 | Introduction | 10 |
| 2.1 | History of speleological exploration of Laos (by J. Dreybrodt & M. Laumanns) | 10 |
| 2.2 | Geological overview (M.Laumanns) | 14 |
| 3 | The caves of the Luang Phrabang province (by J. Burgers, J. Dreybrodt, D. Eskes, M. Laumanns, H. Steiner & W. Zillig) | 15 |
| 3.1 | General remarks | 15 |
| 3.2 | Area A: Nong Khiaw / Muang Ngoy | 16 |
| 3.3 | Area B: Nam Bak | 23 |
| 3.4 | Area C: Ngoy Nua | 26 |
| 3.5 | Area D: Thong–Khang | 37 |
| 3.6 | Area E: Luang | 45 |
| 3.7 | Area F: Xiang Ngeun | 59 |
| 3.8 | Area G: Nam Khan | 67 |
| 3.9 | Area H: Nam Pa | 70 |
| 3.10 | Area I: Phou Khoun | 74 |
| 4 | The caves of the Luang Nam Tha province (by J. Burgers, J. Dreybrodt, M. Laumanns, H. Steiner & W. Zillig) | 79 |
| 4.1 | Area J: Vieng Phouka | 79 |
| 5 | Biospeleological observations | 86 |
| 5.1 | Bats (by Martijn Boonman) | 86 |
| 5.2 | Biospeleological notes on Laos (by Helmut Steiner) | 92 |
| 6 | Conclusions | 97 |
| 7 | References | 98 |
| Annexes | ||
| Caves explored during the 2000, 2002, 2003/04 and 2005 speleological projects | 103 | |
| Photo tables | 106 | |
| The known caves of northern Laos according to map sheets 1 : 100,000 (by H. Steiner) 116 | ||
| Atlas sheets cave survey Tham Nam Eng | 120 | |
| Atlas sheets cave survey Tham Pasat (Nam Mai) | 135 | |
| Atlas sheets cave survey Tham Seua — Nam Lot | 141 |
Northern Laos is virtually unknown to speläology. Only a few reconnaissance projects and three caving expeditions were conducted prior to 2005 in the province of Luang Phrabang: a Dutch expedition (AMIS Laos expedition 2000, with a preparatory trip in 1999) and two German projects in 2002 and 2003/04.
The 2000 AMIS Laos project produced approximately 7,300 m of surveyed passage from 15 caves, including the 2,070 m long system Tham Khan–Pageo (Muang Ngoy, Nam Ou Valley, Ngoy district — now open to tourists), the 1,433 m long Tham Gnai (Nan District), and the 1,028 m long Tham Pha Kouang (Nong Khiaw, Ngoy district), as well as the deepest cave found to date in the region: the –105 m deep Tham Thia (Nan District).
The two German expeditions produced 5,564 m of mapped cave passages from 34 caves, the longest of which was Tham Loum (Xiang Ngeun District) with 1,598 m of passage. Finally a joint Dutch–German project was conducted in February 2005. In the area of Phou Khoun south of Luang Phrabang several caves were linked to form a 2.65 km long cave system (Tham Seua–Nam Lot). A new caving region was visited around Vieng Phouka in the Luang Nam Tha province close to the Thai and Burma borders. The first investigations resulted in significant findings such as Tham Pasat (Tham Nam Mai) at 1,490 m, Tham Nam Eng (Fossil Cave) at 3,120 m, and Tham Nam Eng (Resurgence Cave) at 3,460 m.
Overall, roughly 24.3 km of cave passage has been surveyed to date in northern Laos. This report contains an overview of all visited caving regions with detailed maps and cave descriptions. Additionally, one chapter is dedicated to biospeleological investigations.