Volcano Geology: A Fundamental Tool to Quantify Volcanic Hazards

Abstract

Volcanic hazard assessment relies on analyzing past eruptions documented in historical and geological records to identify potential future eruptive scenarios and assign probabilities to their occurrence. This process involves quantifying geological data, such as the composition, distribution, and textures of volcanic products, to understand magma properties, eruption dynamics, and depositional mechanisms. Such data are crucial for evaluating the potential impact, exposure, and vulnerability of areas at risk from future eruptions. Both probabilistic and deterministic approaches may be used, depending on the purpose of the hazard assessment, but geological data remain the foundation for models that predict volcanic hazards. However, volcanic systems are inherently complex, making it difficult to precisely quantify these data. As a result, only thresholds or ranges are often provided, contributing to significant uncertainty in the assessment. This uncertainty must be clearly communicated for accurate interpretation of the results. Additionally, many active volcanoes lack sufficient data, especially those with long intervals between eruptions, further complicating hazard assessments. Despite these challenges, volcanic hazard assessment is critical for reducing risks and preparing for future volcanic events.