Exploring magma migration before eruptions through 3D X-ray imaging of volcanic rocks: The case of Campi Flegrei caldera (Italy)

A key task in volcanology is correctly interpreting volcano monitoring signals in terms of magma migration to the Earth’s surface. The microcrystals and pores in volcanic rocks record crucial information on magma ascent dynamics. X-ray microtomography enables their effective examination, providing direct 3D imaging of rock microstructures at high resolution. However, cutting-edge phase contrast X-ray imaging and phase retrieval methods, available at synchrotrons, are sometimes needed to properly investigate these rocks due to limited density and chemical contrasts between microcrystals and surrounding matrix glass. We intend to apply these approaches for a systematic analysis of rocks erupted during reference eruptions of the Campi Flegrei caldera, one of Europe's most dangerous volcanoes, in an unrest phase since 2005. Our aim is to obtain a comprehensive dataset on its magma ascent mechanisms and timescales, useful to reconstruct pre-eruptive scenarios and interpret monitoring data.