Uncover the hidden world beneath La Palma’s surface! Recent discoveries reveal the existence of fascinating lava tunnels,offering scientists a unique opportunity to study volcanic processes. This article explores how researchers are using cutting-edge technology like drones to investigate these subterranean formations and gain valuable insights into the formation and cooling of these fascinating geological structures.Read on to learn more about the secrets held within these newly discovered lava tubes.
lava Tunnels Discovered on La Palma Offer Glimpse into Volcanic Cooling
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La Palma,Canary Islands — Barely a month after the start of the La Palma eruption,scientists detected lava tunnels,offering a unique opportunity to study volcanic processes. These subterranean formations, initially invisible to the naked eye, were identified using drone imagery to predict their trajectories.
Unearthing the Subterranean World
The frist tunnel was discovered in June 2022, six months after the eruption concluded, during road construction on the solidified lava flow. Construction workers noticed a cave-like structure, prompting them to halt operations. This discovery led to the involvement of David Sanz Mangas, a scientist who had relocated from Madrid to the Canary Islands to study the eruption’s aftermath. He joined the team adn began exploring the newly found Palma tunnels.
Insights from Hawaii’s Volcanic Caves
Mr. Sanz Mangas referenced data from Hawaii, known for its extensive volcanic cave systems, to inform the exploration strategy.He stated:
Based on the data obtained in Hawaii, where the largest volcanic cavities in the world are, we assumed that exploration of tunnels could start about two years after the eruption.
David Sanz Mangas, Geologist
Though, the La Palma tunnels proved accessible much sooner than anticipated. We discovered that they were already accessible, although hardly,
Mr. Sanz Mangas noted. The rapid accessibility presented an unexpected opportunity for researchers.
Drones: Key to Exploration
Drones have become indispensable tools in the exploration of these tunnels. mr. Sanz Mangas explained their crucial role:
For their exploration, drones play a crucial role. The first step was to make a series of flights with thermal cameras to locate the presence of holes in the lava field.
David Sanz Mangas
Thermal imaging allows scientists to identify areas where heat escapes from the tunnels, indicating potential entry points and providing valuable data on the tunnels’ structure and thermal properties.
The “Red Tunnel” and Todoque’s Fate
One notable tunnel, dubbed the “Red Tunnel,” was formed by lava flows that engulfed the town of Todoque three years prior. Today, two openings, separated by more than 60 meters, facilitate air circulation within the tunnel.Octavio Fernández lorenzo explained the airflow dynamics:
Instead of exhaling hot air, the mouth aspires fresh air from the outside. This is the best laboratory we have to understand how the flow cools.
Octavio Fernández Lorenzo
Entering the Red Tunnel reveals a striking landscape. We light our front lamps, we slide inside the tunnel and we find in front of the surprising red color of its walls. From the ceiling hang lava stalactites from a dark brown, like drops of melted chocolate,
Mr. Fernández lorenzo described. The air inside the tunnel is cooler than the walls, with temperatures ranging from 122 to 212 degrees Fahrenheit (50 to 100 degrees Celsius).
Speleologists use thermal drones to measure temperatures within the tunnels. Just 100 meters from the entrance, the heat intensifies substantially. At one point, the tunnel narrows, and the drone registers temperatures exceeding 482 degrees Fahrenheit (250 degrees Celsius). The extreme heat creates a visible distortion in the air, resembling a mirage.
Challenges of Tunneling in Volcanic Rock Masses
According to research, volcanic rock masses present unique challenges due to their temporal and spatial variability [1]. Volcanic processes are dynamic, resulting in rock masses that range from highly porous, clay-rich, fractured, and soil-like to low-porosity, high-strength, brittle, and massive. These variations can significantly impact tunneling and exploration efforts.
The Genesis of Lava Tubes
Lava tubes, also known as pyroducts, form as lava flows erode downward, creating underground canyon-like tunnels with rivers of low-viscosity lava at the bottom [2]. Back-cutting lavafalls can quickly enlarge these tunnels,contributing to their complex structure.
Trans-Koolau Tunnel Study
A study of the Trans-Koolau (T-K) tunnel on Oahu, Hawaii, provides insights into lava flows and dikes in a near-vent facies [3]. The T-K tunnel sequence, dominated by lava flows with some dikes and pyroclastic layers, offers a valuable comparison for understanding the geological context of lava tunnels in different volcanic settings.
