In recent months, there have been several changes to the surface of the fumarolic fields in Furnas, on the island of São Miguel. However, experts say that these changes are part of internal dynamics and do not pose a danger to the population.

Over the last few months, there have been changes on the surface in the Caldeiras (boiling pools) areas of Furnas, in the municipality of Povoação. Experts consider the situation to be normal, but for those unfamiliar with the dynamics of volcanism, it may cause some concern.

The director of the Institute of Volcanology and Risk Assessment at the University of the Azores explained that the slope movements “are related to the fact that the slopes are mainly composed of unconsolidated pomitic ash deposits, which can be enhanced by weather conditions or seismic activity.”

In any case, Fátima Viveiros emphasized that the Institute for Volcanology and Risk Assessment “has been taking measurements in the fumarolic fields of Furnas since the 1990s because volcanic gases can be indicators of volcanic activity.”

But the research/monitoring does not stop there. “In addition to the volcanic gases measured in fumaroles, soils, lagoons, and springs, information on seismic activity or Earth deformation, for example, are other preferred techniques for understanding the state of volcanic activity and can be precursors of anomalous activity,” she said.

Fátima Viveiros clarified that “currently, IVAR, in collaboration with the Azores Seismic-Volcanic Information and Surveillance Center (CIVISA), monitors and studies the active volcanoes in the Azores, and the Furnas volcano has a volcanic activity alert level considered normal. The data recorded so far does not indicate any significant changes in recent years in terms of gas emissions, essentially in terms of its composition.”

In order to clarify what is happening at the Furnas volcano

Diário da Lagoa spoke with Fátima Viveiros, director of the Institute of Volcanology and Risk Assessment at the University of the Azores, who clarified that “fumarolic fields may undergo surface changes that result from their own dynamics and do not necessarily represent changes in the volcanic and/or hydrothermal system at depth.”

In addition, she added, “the deposition of alteration minerals and changes in permeability at the surface levels of the terrain can condition the path of the gas to the surface and, consequently, result in visible changes in fumarolic emissions.”

Added to this are rainfall and potential changes in aquifer levels, which “may result in the presence of water in some fumaroles that were temporarily dry.” In other words, “although the dynamics could potentially result in damage due to surface collapse, they do not in themselves represent variations in the volcanic system,” she pointed out.

However, Fátima Viveiros made it clear that “all recommendations and access restrictions defined by the civil protection authorities must be respected and complied with.”

This is the case of Lagoa das Furnas, which “also emits volcanic gases and, in the northern part of the lagoon, next to the fumarolic field, gas bubbles (mainly carbon dioxide) can be seen along the banks, which in some places are also associated with higher temperatures,” she explained.

Measurements do not indicate risks

The director of the Institute of Volcanology and Risk Assessment at the University of the Azores also explained that the slope movements “are related to the fact that the slopes are mainly composed of unconsolidated pomitic ash deposits, which can be exacerbated by weather conditions or seismic activity.”

In any case, Fátima Viveiros emphasized that the Institute for Volcanology and Risk Assessment “has been taking measurements in the fumarolic fields of Furnas since the 1990s because volcanic gases can be indicators of volcanic activity.”

But the research/monitoring does not stop there. “In addition to the volcanic gases measured in fumaroles, soils, lagoons, and springs, information on seismic activity or Earth deformation, for example, are other preferred techniques for understanding the state of volcanic activity and can be precursors of anomalous activity,” she said.

Fátima Viveiros clarified that “currently, IVAR, in collaboration with the Azores Seismic-Volcanic Information and Surveillance Center (CIVISA), monitors and studies the active volcanoes in the Azores, and the Furnas volcano has a volcanic activity alert level considered normal. The data recorded to date do not indicate any significant changes in recent years in terms of gas emissions, essentially in terms of their composition.”

Acácio Mateus, colaborator for Diário da Lagos, Clife Botelho-director.

Translated into English as a community outreach program by the Portuguese Beyond Borders Institute (PBBI) and the Modern and Classical Languages and Literatures Department (MCLL), in collaboration with Bruma Publication and ADMA (Azores-Diaspora Media Alliance) at California State University, Fresno. PBBI thanks Luso Financial for sponsoring NOVIDADES.