Muography as a new complementary tool in monitoring volcanic hazard: implications for early warning systems

Muography uses muons naturally produced in the interactions between cosmic rays and
atmosphere for imaging and characterization of density differences and time-sequential
changes in solid (e.g. rocks) and liquid (e.g. melts±dissolved gases) materials in scales from
tens of metres to up to a few kilometres. In addition to being useful in discovering the secrets
of the pyramids, ore prospecting and surveillance of nuclear sites, muography successfully
images the internal structure of volcanoes. Several field campaigns have demonstrated that
muography can image density changes relating to magma ascent and descent, magma
flow rate, magma degassing, the shape of the magma body, an empty conduit diameter,
hydrothermal activity and major fault lines. In addition, muography is applied for longterm
volcano monitoring in a few selected volcanoes around the world. We propose using
muography in volcanomonitoring in conjunction with other existing techniques for predicting
volcanic hazards. This approach can provide an early indication of a possible future eruption
and potentially the first estimate of its scale by producing direct evidence of magma ascent
through its conduit in real time. Knowing these issues as early as possible buy critically
important time for those responsible for the local alarm and evacuation protocols.