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Major volcanic eruptions (e.g., VEI>4) have provided valuable lessons for understanding volcanic hazards and have helped advance the field of volcanology. However, it is usually rare to experience a major eruption even several times in our lifetime. Most active volcanoes are typically in an unrest state, characterized by events including, but not limited to, transient volcanic earthquake swarms, ground deformation, and surface thermal anomalies. One of our ultimate goals is to gain a future perspective on volcanic activity beyond the unrest, although numerous challenges lie ahead. In this session, we aim to bridge this "gap" by considering unrest as a precursor or aftermath of major eruptions. In particular, the primary driving process of a major eruption is magma intrusion towards the surface from a subsurface reservoir. What observable precursors are expected from our cutting-edge understanding of magma reservoir and intrusion processes? In the other direction, how is the magma reservoir expected to form from the ongoing unrest activities? For example, recent advances in thermomechanical magma reservoir dynamics and magma fracture processes may provide us with direct insights into the link between the magma reservoir and unrest manifestations. Detailed long-term onsite observation (e.g., seismic, geodetic, thermal, and geochemical) and geological and petrological investigations may also provide insight into the hosting magma reservoir and any potential related shallower hydrothermal system. Degassing from a magma reservoir can be a fundamental key to interpreting the physics behind any continuous unrest activity, and where experimental and numerical approaches are highly essential for the understanding.
The JpGU-AGU 2026 is an excellent opportunity for such a challenging yet aspirational discussion. We welcome submissions from various fields including those with observational, computational, or experimental approaches, and beyond the existing research frameworks.