Tracking the Deep Secrets of Volcanoes with “Volcano Detectives”

The last eruption of Ciomadul occurred around 30,000 years ago. Although this may seem unimaginably long on a human timescale, it is not unusual from a volcanological perspective. Many volcanoes around the world have resumed activity after even longer dormant periods, and Ciomadul itself experienced pauses of tens of thousands, and in some cases more than one hundred thousand years between eruptive episodes. For this reason, Ciomadul is regarded as a characteristic example of a long-dormant volcano.

At the Volcano Day, held on 1^st June, Réka Lukács, Scientific Advisor and leader of the MTA–HUN-REN–CSFK “Lendület” (Momentum) PannonVolcano Research Group, explained how researchers investigate what lies beneath the volcano. One of their most important sources of information is the tiny zircon crystals found in volcanic rocks. These microscopic minerals form in magma reservoirs beneath the surface long before eruptions occur, preserving information that allows researchers to reconstruct the evolutionary history of the volcanic system.

Research on Ciomadul does not rely on a single method. Instead, scientists combine geochemical, petrological and geophysical evidence to build a comprehensive picture of the volcano’s current state. During the Volcano Day lectures, Barbara Cserép, Csaba Jánosi, Boglárka-Mercédesz Kis and Szabolcs Harangi presented results that each contribute another piece to the puzzle of how the volcanic system works.

There are many active surface manifestations which help the researchers’ studies. Carbon dioxide gas emissions, bubbling pools, sparkling mineral water springs indicate that deep geological processes are still ongoing at depth. Measurements suggest that more than 8,000 tonnes of carbon dioxide reach the surface at Ciomaduleach year, a substantial proportion of which is of magmatic origin. While these observations alone do not prove the presence of magma, together with petrological and geophysical evidence they support the hypothesis that a magma reservoir containing some melt may still exist beneath Ciomadul.

This does not mean that an eruption is imminent, there is currently no evidence suggesting such a scenario. In many parts of the world, magma is known to be present within the Earth's crust without posing any immediate volcanic threat. Nevertheless, continuous research and instrumental monitoring remain essential for understanding the state of volcanic systems and detecting any future changes.

The aim of Volcano Day was to give visitors an opportunity to gain insight into a scientific “detective work”, helping them to better understand the behaviour and present condition of the youngest volcano in our region. The lectures were complemented by volcanic eruption simulations, field demonstrations and hands-on measurements, offering an engaging introduction to both volcanic processes and the methods used by volcanologists. The organisers hope that the Volcano Day event will become a tradition, providing an annual opportunity for the public to hear directly from researchers about the latest discoveries emerging from beneath Ciomadul.