At the beginning of August 2018 an expedition took place with a seven membered scientific team, under the supervision of prof. Eric Ferré from the Southern Illinois University, U.S. in the area of Ariège (in the South of France), in the cave of Geuffre Georges, which is situated in the massif of the Mont Bèas mountain (1903 altitude) in the northern Pyrenees. Members of the scientific team were also doc. Mgr. Michal Gallay, PhD. and Mgr. Jozef Šupinský from the Institute of Geography FS P.J.Š. University.
The expedition took place with the help of eight expert cavers of the French club called Spéléo Club du Haut Sabarthez based in Tarascon sur Ariége. It was strictly followed by local and French journals called La Depeche du Midi a L´Ariegeois. According to doc. Gallay, Pyrenees from a geological point of view is a mysterious range of mountains in which the standardly accepted models of folding and the related escape of rocks from the Earth´s mantle are not valid. Exactly these kinds of tectonics and rock formations on the border of the Earth´s crust and mantle are being researched over a long period by professor Eric Ferré. The professor addressed a team of geologists from France and a team from the Institute of Geography from the FS, P.J.Š. University in 2017 with the aim of mapping in detail the orientation and direction of the layers and cracks, dating the age of rocks and to get a detailed 3D model from one of the branches from a cave as extensive as the Gouffre Georges which is similar to a cave called Mesačný tieň in the Western Tatras.
Cave Gouffre Georges, which is a few kilometres long, was created by contacting with marble, which lets the water through, and ultramafic igneous rocks (more precisely Lherzolite) which come from a depth of some ten and thousands of kilometres. The cave was also strongly formed by a mechanical erosion of waters from melting glaciers, which at the end of the ice ages went below the surface and carried a lot of materials with themselves from the outside. Spaces under the surface got bigger with the falling of marble blocks from the ceiling of the cave, with their further erosion and water denudation.
„The intensity of the erosion can be concluded by calculating the volume of the missing rocks. This cave gave us a unique chance of watching directly the placing of these two types of diametrically different rocks and this way finding out the way how did the marble and Lherzolite get mixed up. Our task was to make a laser scanning in a passage with approximately 200 m length and 200 m elevation difference. The movement throughout the cave needed a usage of climbing equipment and we also had to manage to transfer carefully the laser scanner and other accessories through the terrain which looked like an upturned peak of the Tatra mountains below the surface. For this aim we used our laser scanner Riegl VZ-1000, which is suitable especially for expanded cave spaces, during the scanning it not only records 3D items but also the scaled reflectance of laser rays. The scanning would not be possible without the special equipment which we got with the help of our colleague from the institute, an experienced speleologist, doc. Zdenko Hochmuth. Before we traveled to France we took part in a basic climbing preparation and motion testing in demanding spaces of the cave Skalistý potok” – said doc. Gallay.
We can state that to the invitation to an interesting international team, under the supervision of professor Ferré from the U.S., has contributed wide practical experience and scientific results of the team ÚGE (experience with mapping demanding cave spaces of caves Domica and Silická ľadnica with using a laser scanner for modelling the flowing of the cave´s waters, or more precisely the ice loss, experience with scanning the urban green vegetation of Košice and of Malá studená dolina and others). The primary aim of the expedition is, according to doc. Gallay, not only to publish the achieved results in scientific journals but also to engage National Geographic Society´s attention for getting a financial support for the scientific expedition to the Gouffre Georges cave in the South of France also in the future.
The expedition was financed by the MESRS SR within the project called VEGA 1/0963/17: Dynamics of the country in high resolution. The laser scanner was imported within the building of the University´s Scientific Park TECHNICOM co-financed by structural funds of the European Union (ITMS: 26220220182, ITMS2014+: 313011D232).