Lidar

Here are some Lidar projects in Belgian caves:

• Trotti aux Fosses
• Grotte Pére Noël
• Salle Daniel Amey dans la Gouffre Belvaux
• Grotte de Han sur Lesse
• Trou d'Haquin
• Grotte de la Fontaine du Rivire

As you can see the resulting point clouds contains much more information then what an caver normally sees when in the cave. Fractures, fissures, Faults, joints and layers are particularly well highlighted. This opens new ways in understanding the geology of the caves.

Trotti aux Fosses

This is the classic survey by Paul Vandersleyen of a small cave in Belgium, the Trotti aux Fosse. A 10 m pit gives access to a chamber 25 m deep. The bedding planes and joints in the limestone rock are well exposed. Although standing there it is very difficult to get the overview. On the topo you can see an artistic interpretation of these geological features.

We scanned this cave and here are two side view pictures in the fascinating and popular X-ray vision format. These are very well suited to get an overview of the system but the geological features are not well exposed.

The animation shows the rendered point cloud. The bedding planes and joints really stand out and are so easier to study by cave scientists. 

Grotte Pére Noël

We were very lucky to be able to scan the very beautiful Pére Noël Cave. This cave is much more difficult when compared to the only existing topo by Paul Vandersleyen. Based on his survey you start to think this is a horizontal cave. Once inside this cave you'll have a very hard time to even find a square foot horizontal ground.

We needed seven monster sessions in the Pére Noël cave totaling of 384 scans! The final model has 218 M points and a resolution of 2 cm. Smaller resolutions are not really an option because the file size is already very large. 

Thank you to all the people who helped me during all these long sessions:
Loran, Joël, Jean-Michel, Marjorie, Lionel, John, Carine, Kira, Ines, Marie, Wouter, Lies, Sandy, Renzo, Marc, An, Dirk, Eli, Jolan and Hilde. 

Salle Daniel Ameye dans la Gouffre Belvaux

We measured the Salle Daniel Ameye in the Gouffre Belvaux above and below the water with the Faro Lidar and our mini-sonar boat. The white part is above the water measured with the lidar. The colored points are measured with the sonar boat. The blue points are the deepest: 4.2 m. The water is comming from the Salle du 5 Mars and has to pass the second siphon at the the top of our survey. This siphon is 30 m long and 3 m deep.

The Gouffre Belvaux is one of the natural wonders of Belgium where the river Lesse disappears underground and emerges back at the surface in the Grotte of Han. A long time this siphon (45 m deep and 180 m long) was unbreakable and unfortunately some divers lost their lives in their attempt to discover the mystery of the underground Lesse. Now cavers have dug a small 110 m tunnel to bypass this dreadfull siphon. Getting all the equipment in place through the low crawl spaces and acrobatic passages is a challenge.

Grotte de Han sur Lesse

Trou d'Haquin

Grotte de la Fontaine du Rivire