GPS and seismic networks integrated with magnetic stations and infrared satellite images , Live camera images displaying the textural and compositional analysis of the material produced during and after eruptions , Ground-based, airborne and space-borne measurements of gas emissions (e.g. For this reason, a multidisciplinary approach is often applied to volcanic monitoring, including at least some of the following methods:įield observation integrated with space-borne data, interferometric synthetic aperture radar (InSAR) using ENVISAT-ASAR and ALOS-PALSAR (although now out of service), RADARSAT-2, TerraSAR-X and TanDEM-X imagery , The appraisal and mitigation of volcanic hazards also require a deep understanding of volcano-specific histories and tracking magma movement in real time. Volcanic monitoring requires a deep understanding of the volcanic processes related to every single volcanic centre within the given volcanic system. The aim of this paper is to review how muography could be useful in monitoring volcanic hazards as a standard addition to the state-of-the-art volcano monitoring systems.įorecasting violent volcanic eruptions is the Holy Grail for applied volcanology. Consequently, the high-energy muons can penetrate deeper regions underground than most particles. However, apart from muons, all these particles are naturally filtered out once they hit the upmost layers of soil or rock. For muography, all particles except muons are background noise and hence potentially harmful for particle identification. Analysis techniques have been developed for muons that provide three levels of purity versus efficiency, following the criteria in. Muons are unstable, decaying into electrons and neutrinos with a mean lifetime of 2.2 μs muons' larger mass than electrons, the absence of strong nuclear interactions, negligible probability of producing electro-magnetic cascades and relatively small energy losses by ionization make them a good tool for imaging of large-scale structures on Earth. Therefore, they can be considered as a nearly time-independent, continuous, particle source. Most muons reaching the Earth's surface originate from a constant flux of medium to high-energy (from 100 MeV to 10 20 eV) cosmic-ray particles of galactic origin as observed by Cherenkov or fluorescence light apparatus. A single cascade may consist of millions of particles. Muons-be they negative or positive-form the basis for muography, a novel method that uses the detection of muons that are a major component of extensive air showers formed in the upper atmosphere from collisions between high-energy cosmic-ray particles and atmospheric nuclei. Its corresponding antiparticle, called antimuon, has a positive charge, which explains why it is also known as the positive muon. Knowing these issues as early as possible buy critically important time for those responsible for the local alarm and evacuation protocols.Ī muon is an elementary particle similar to the electron but with a much greater mass (about 207 times greater). 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. We propose using muography in volcano monitoring in conjunction with other existing techniques for predicting volcanic hazards. In addition, muography is applied for long-term volcano monitoring in a few selected volcanoes around the world. 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 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. melts ± dissolved gases) materials in scales from tens of metres to up to a few kilometres. 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.