Mapping the underworld
Deep beneath our feet lies a vast unexplored realm of cavities and streams, that holds secrets of our hydrology and the geology our planet. Underground exploration (speleology, mining, archaeology and infrastructures) is being changed by technological advances in telemetry. LIDAR technologies allow underground mapping, reconstructing and virtual reality tour of the most inaccessible chambers while preserving the fragile fauna, bacteria and rock formations.
A pair of troglodyte creatures in their natural habitat
View from the inside of Saint-Leonard cavern.
Starting in January 2018, a team of 12 students visited a newly discovered chamber at caverne de Saint-Léonard and performed the first-ever measurements in the newly discovered chamber called the cathedral.
UV fluorescence was employed to highlight the presence of certain mineral formations such as limestone (Calcium carbonate) as this mineral re-emits incident photons across the light spectrum. This technique also highlighted the presence of colonies of troglodyte bacteria on the walls of the cavern, which glows with a special hue of green or orange when lit with a black-light.
By this mission, UBERG students made sure that a newly discovered part of the cave with restrained access would be made accessible for virtual visits. The students tested new data acquisition techniques for the 3D structure of caverns.
This LIDAR technique improves field acquisition of data while gathering new information.
An example of the inside of the cavern as reconstructed by the LIDAR system. We clearly see the ladder used to access the chamber. Almost as if we were there!
The use of several LIDAR scands constitutes a fast method for 3D scanning the surface inside the cavern, in colour, and at a resolution higher than the centimetre.
