Possible application of compact electronics for multilayer muon high-speed radiography to volcanic cones

Abstract

Abstract. Compact data-taking electronics were developed for high-speed multilayer muon radiography in order to minimize operation failure rates. By requiring a linear trajectory within the position sensitive detectors (PSDs), the background (BG) events produced by vertical electromagnetic (EM) showers are effectively reduced. In order to confirm the feasibility of this method, the system comprising four PSD layers was tested by imaging the internal structure of a parasitic cone and the adjacent craterlets formed in the 1910 eruption at the base of the Usu volcano, Hokkaido with a conventional (MURG08) readout system (Kusagaya et al., 2012;Uchida et al., 2009). The new mountain is believed to be a cryptodome since its formation. As knowledge on lava domes is accumulated at various volcanoes, the definition of "cryptodome" is now doubted in its validity. The results of the preliminary 290 h muon radiographic survey revealed that the "cryptodome" is not underlain by any lava mass and that a main craterlet is accompanied by magma intrusions at shallow depths. The former verifies that the new mountain is not a cryptodome but a volcanogenetic mound, and the latter interprets the phreatic explosions forming the craterlets as intrusions of magma into the aquifer. However, a higher data taking failure rate was observed with a softwarebased MURG08 system when the size of the active area of the detection system was enlarged to improve the detection ability of the system. The newly developed MURG12 is a complete electronics system that can simultaneously process signals from 192 scintillation counters with a data size of 600 kbps ch −1 without operation failure. We anticipate that the observation speed would be further improved by employing MURG12.At the base of the Usu volcano, in the 20th century, four eruptions occurred. Some of them demonstrated three characteristic stages of magma intrusions. First, a magma branch remained at a depth leaving an upheaval of the ground; second, it rose and reached aquifers causing phreatic explosions without extrusions; and third, it reacted with aquifers causing phreatic explosions and further extruded over the ground forming a lava dome. In order to clarify the eruption mechanism of Usu, it is necessary for us to image many parasitic cones. Based on the result of the test measurement, we anticipate that MURG12 would be a strong tool for high-speed muon radiography.

Development of the very long-range cosmic-ray muon radiographic imaging technique to explore the internal structure of an erupting volcano, Shinmoe-dake, Japan

“…However, the telescopes have needed to be placed in the vicinity (0.5-1.6 km) of the volcano craters (Tanaka et al, , 2010b(Tanaka et al, , 2009a(Tanaka et al, , b, 2007aDe Lellis et al, 2014;Tanaka and Yokoyama, 2013;Carbone et al, 2013;Kusagaya et al, 2013;Lesparre et al, 2012;Hernández et al, 2013;Miyamoto et al, 2012) (Fig. 1).…”

“…For example, Tanaka et al (2014) reduced electromagnetic background events by adding redundant detectors and radiation shields to a conventional muography telescope (e.g., Tanaka and Yokoyama, 2013), thereby improving the time resolution. They successfully visualized magma movements with a time resolution of 3 days.…”

Plug Formation Imaged Beneath the Active Craters of Sakurajima Volcano With Muography

“…The application of cosmic muons has a potential to obtain the subsurface density structure of these craters and reveal the cause of deactivation of Showa crater and activation of Minamidake. Muography allows to image the shape of the magma either deposited or intruded Nishiyama et al, 2014Nishiyama et al, , 2017Tanaka & Yokoyama, 2013;Kusagaya & Tanaka, 2015), empty pathways Tioukov et al, 2019), magma degassing , magma ascent and descent , and hydrothermal activity inside lava domes (Jourde et al, 2016).…”

“…Muography allows to image the shape of the magma either deposited (Tanaka et al, ) or intruded (Tanaka et al, ; Nishiyama et al, , ; Tanaka & Yokoyama, ; Kusagaya & Tanaka, ), empty pathways (Tanaka et al, ; Tioukov et al, ), magma degassing (Tanaka et al, ), magma ascent and descent (Tanaka et al, ), and hydrothermal activity inside lava domes (Jourde et al, ).…”

Muography and Its Potential Applications to Mining and Rock Engineering

“…Up till now muography has been applied to or tested in many fields. For example, muography has been used in the imaging of volcanoes (Nagamine et al 1995;Tanaka et al 2007Tanaka et al , 2009Tanaka et al , 2014Okubo and Tanaka 2012;Lesparre et al 2012;Marteau et al 2012Marteau et al , 2015Shinohara and Tanaka 2012;Carlôganu et al 2013;Tanaka and Yokoyama 2013;Nishiyama et al 2014;Ambrosino et al 2015b;Jourde et al 2016;Tioukov et al 2017;Noli et al 2017;Kaiser 2019;D'Alessandro et al 2019;Oláh et al 2019;Tanaka 2019;Barnoud et al 2019;Lelièvre et al 2019), in mining exploration (Schouten 2019), in the imaging of underground structures (Bonneville et al 2019;Saracino et al 2019), in archaeology and tunnel detection (Basset et al 2006;Menichelli et al 2007;Levy et al 1988;Celmins 1990;Caffau et al1997;Morishima et al 2017), in the monitoring of carbon capture storage sites (Kudryavtsev et al 2012;Jiang et al 2013;Klinger et al 2015;Gluyas et al 2019), in scanning old mining sites to detect the possible presence of unknown cavities (Baccani et al 2019;Mitrica et al 2019), in investigation of mineral deposits and rock density measurements…”