In October 2021, prospecting was held in Iceland for the “Hraun” project organized by the Italian association La Venta Esplorazioni Geografiche. As part of this project we have dealt with the realization of photogrammetric and thermal surveys from drones, documenting various entrances of lava tubes formed a few weeks ago on the flanks of the Fagradasfjall volcano.
As we had hoped for the purposes of the project, the eruption was interrupted with the event of 17-20 September, therefore the mappings we have created represent an effective starting point for the speleological explorations that La Venta plans to undertake in May June 2022. During the numerous flyovers, 324 thermal images were acquired, covering 5 different areas, including the large portal from which the last active casting was generated in September. At the time of filming, the surface of the lava has already partially cooled, with areas that still exceed 70 ° centigrade. Inside the inlets and collapses we measured temperatures approaching 200 °, while inside the pipes the temperatures are certainly much higher.
Fagradalsfjall volcano drone thermal analysis
During the many rainy days when it was not possible to fly with the thermal drone, we took advantage of the hospitality of the Icelandic Speleological Society to visit some caves being explored in the Reykjanes peninsula. Of particular interest was the realization of the three-dimensional survey with laser scanner of the Búri lava tube, one of the largest and most spectacular known conduits in Iceland, discovered only in 2005.
The study of tubes formed in more ancient eruptions in the vicinity of the Fagradalsfjall allows us to have a greater knowledge of speleogenetic processes, helping us to predict what we may encounter inside the newly formed cavities.
This project is supported by Kibo.it, Studio Atlante, Vigea, Miles Beyond, Ferrino, Tiberino, Amphibious, Scurion, and carried out in collaboration with Veðurstofa Íslands (Icelandic Met Office), University of Iceland, Icelandic Speleological Society, National Institute of Astronomy and Physics, University of Bologna and University of Padua, under the patronage of the Italian Speleological Society. Special thanks to Dr. Sara Barsotti of the Veðurstofa Institute, aÞórir Már Jónsson and Guðni Gunnarsson of the Icelandic Speleological Society for their support and hospitality.