Temporal variation in chemical composition of the volcanic plume from Aso volcano, Japan, measured by remote FT-IR spectroscopy

Mori, Toshiya; Notsu, Kenji

doi:10.2343/geochemj.42.133

Cited by 18 publications

(11 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, the detailed thermal structure around Aso volcano is poorly understood, although some thermal gradient measurements have been undertaken in the area (e.g., Tanaka et al 2004). Fumarolic activity has been continuously observed at Nakadake cone, the only active caldera cone in Aso volcano (e.g., Mori and Notsu 2008). A zone of low seismic velocity at 5-6 km below Nakadake has been previously interpreted as a shallow magma reservoir (Sudo and Kong 2001).…”

Section: Introductionmentioning

confidence: 95%

“…Fumarolic activity has been continuously observed and the large eruption occurred five months after the 2016 Kumamoto earthquake at Nakadake, where the SLDB is located (Mori and Notsu 2008;Japan Meteorological Agency 2016a). Therefore, the SLDB is thought to correspond to the magma reservoir that feeds the ongoing surface activity.…”

Section: Density Structures and Their Interpretationsmentioning

confidence: 99%

See 1 more Smart Citation

Volcanic magma reservoir imaged as a low-density body beneath Aso volcano that terminated the 2016 Kumamoto earthquake rupture

Miyakawa

Sumita

Okubo

et al. 2016

Earth Planets Space

View full text Add to dashboard Cite

We resolve the density structure of a possible magma reservoir beneath Aso, an active volcano on Kyushu Island, Japan, by inverting gravity data. In the context of the resolved structure, we discuss the relationship between the fault rupture of the 2016 Kumamoto earthquake and Aso volcano. Low-density bodies were resolved beneath central Aso volcano using a three-dimensional inversion with an assumed density contrast of ±0.3 g/cm 3 . The resultant location of the southern low-density body is consistent with a magma reservoir reported in previous studies. No Kumamoto aftershocks occur in the southern low-density body; this aseismic anomaly may indicate a ductile feature due to high temperatures and/or the presence of partial melt. Comparisons of the location of the southern low-density body with rupture models of the mainshock, obtained from teleseismic waveform and InSAR data, suggest that the rupture terminus overlaps the southern low-density body. The ductile features of a magma reservoir could have terminated rupture propagation. On the other hand, a northern low-density body is resolved in the Asodani area, where evidence of current volcanic activity is scarce and aftershock activity is high. The northern low-density body might, therefore, be derived from a thick caldera fill in the Asodani area, or correspond to mush magma or a high-crystallinity magma reservoir that could be the remnant of an ancient intrusion.Keywords: 2016 Kumamoto earthquake, Density structure, Gravity inversion, Volcano-tectonic interactions © The Author(s) 2016. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. BackgroundThe 2016 Kumamoto earthquake (M JMA 7.3) occurred on April 16, 2016, at 01:25 Japan Standard Time (JST, UTC +9) in the Kumamoto region, Kyushu Island, southwestern Japan. The epicenter (32.76°N, 130.76°E) and hypocentral depth (12 km below sea level) determined by the Japan Meteorological Agency (JMA) are very close to Aso volcano, the largest active volcano with a large caldera (15 × 25 km) in Japan (Fig. 1). The rupture process of the 2016 Kumamoto earthquake was resolved by Yagi et al. (2016): Rupture initiated at the hypocenter on the southwest part of the focal plane and propagated east for about 17 s. The area of maximum slip, with a value of ~5.7 m, was centered ~10 km northeast of the epicenter. The effective slip area was about 40 km long and 15 km wide, and the total seismic moment was 5.1 × 10 19 Nm (M w = 7.0). Aftershock distributions and focal mechanism determined by Yagi et al. (2016) indicate that the 2016 Kumamoto earthquake occurred along an active strike-slip fault known as the Futagawa Fault (Research Group for Active Faults of Japan 1991), which bel...

show abstract

Section: Introductionmentioning

confidence: 95%

Section: Density Structures and Their Interpretationsmentioning

confidence: 99%

Volcanic magma reservoir imaged as a low-density body beneath Aso volcano that terminated the 2016 Kumamoto earthquake rupture

Miyakawa

Sumita

Okubo

et al. 2016

Earth Planets Space

View full text Add to dashboard Cite

show abstract

“…350°C in May, 2010) must be lower than the actual outlet, by at least 150°C. Furthermore, Mori and Notsu (2008) determined CO/CO 2 ratios of the fumarolic gases at the Aso volcano remotely using FT-IR on six occasions from 1996 to 2003, and estimated the equilibrium temperature of fumarolic gases was almost stable at 670-870°C, using the empirical relation between the equilibrium temperatures and CO/CO 2 ratios in the fumarolic gases. Shinohara et al (2010) also obtained similar equilibrium temperatures from 750 to 950°C for the fumarolic gases during the observations from 2006 to 2009 using both H 2 /H 2 O ratios and SO 2 /H 2 S ratios in the volcanic plume determined by using a portable multisensor system (Shinohara, 2005).…”

Section: Application To Remote Temperature Sensing On the Aso Volcanomentioning

confidence: 99%

Hydrogen isotopes in volcanic plumes: Tracers for remote temperature sensing of fumaroles

Tsunogai

Kamimura

Anzai

et al. 2011

Geochimica et Cosmochimica Acta

View full text Add to dashboard Cite

In high-temperature volcanic fumaroles (>400°C), the isotopic composition of molecular hydrogen (H 2 ) reaches equilibrium with that of the fumarolic H 2 O. In this study, we used this hydrogen isotope exchange equilibrium of fumarolic H 2 as a tracer for the remote temperature at volcanic fumaroles. In this remote sensing, we deduced the hydrogen isotopic composition (dD value) of fumarolic H 2 from those in the volcanic plume. To ascertain that we can estimate the dD value of fumarolic H 2 from those in a volcanic plume, we estimated the values in three fumaroles with outlet temperatures of 630°C (Tarumae), 203°C (Kuju), and 107°C (E-san). For this we measured the concentration and dD value of H 2 in each volcanic plume, along with those determined directly at each fumarole. The average and maximum mixing ratios of fumarolic H 2 within a plume's total H 2 were 97% and 99% (at Tarumae), 89% and 96% (at Kuju), and 97% and 99% (at E-san). We found a linear relationship between the depletion in the dD values of H 2 , with the reciprocal of H 2 concentration. Furthermore, the estimated end-member dD value for each H 2 -enriched component (À260 ± 30& vs. VSMOW in Tarumae, À509 ± 23& in Kuju, and À437 ± 14& in E-san) coincided well with those observed at each fumarole (À247.0 ± 0.6& in Tarumae, À527.7 ± 10.1& in Kuju, and À432.1 ± 2.5& in E-san). Moreover, the calculated isotopic temperatures at the fumaroles agreed to within 20°C with the observed outlet temperature at Tarumae and Kuju. We deduced that the dD value of the fumarolic H 2 was quenched within the volcanic plume. This enabled us to remotely estimate these in the fumarole, and thus the outlet temperature of fumaroles, at least for those having the outlet temperatures more than 400°C. By applying this methodology to the volcanic plume emitted from the Crater 1 of Mt. Naka-dake (the volcano Aso) where direct measurement on fumaroles was impractical, we estimated that the dD value of the fumarolic H 2 to be À172 ± 16& and the outlet temperature to be 868 ± 97°C. The remote temperature sensing using hydrogen isotopes developed in this study is widely applicable to many volcanic systems.

show abstract

“…Aerosol is simulated according to continental cumulus described by Pruppacher and Klett 13 but with a 10 times less numerical concentration. Background CO 2 concentration is 391 ppm, while maximum CO 2 concentration in the volcanic plume 14 is 2×10 5 ppm. Both aerosol and CO 2 profiles are assumed to be Gaussian ( Figure 5).…”

Section: Lidar Simulationmentioning

confidence: 99%

Lidar sounding of volcanic plumes

Fiorani

Aiuppa

Angelini

et al. 2013

Lidar Technologies, Techniques, and Measurements for Atmospheric Remote Sensing IX

View full text Add to dashboard Cite

Accurate knowledge of gas composition in volcanic plumes has high scientific and societal value. On the one hand, it gives information on the geophysical processes taking place inside volcanos; on the other hand, it provides alert on possible eruptions. For this reasons, it has been suggested to monitor volcanic plumes by lidar. In particular, one of the aims of the FP7 ERC project BRIDGE is the measurement of CO 2 concentration in volcanic gases by differential absorption lidar. This is a very challenging task due to the harsh environment, the narrowness and weakness of the CO 2 absorption lines and the difficulty to procure a suitable laser source. This paper, after a review on remote sensing of volcanic plumes, reports on the current progress of the lidar system.

show abstract

Temporal variation in chemical composition of the volcanic plume from Aso volcano, Japan, measured by remote FT-IR spectroscopy

Cited by 18 publications

References 21 publications

Volcanic magma reservoir imaged as a low-density body beneath Aso volcano that terminated the 2016 Kumamoto earthquake rupture

Volcanic magma reservoir imaged as a low-density body beneath Aso volcano that terminated the 2016 Kumamoto earthquake rupture

Hydrogen isotopes in volcanic plumes: Tracers for remote temperature sensing of fumaroles

Lidar sounding of volcanic plumes

Contact Info

Product

Resources

About