5:15 PM - 6:30 PM
[SVC28-P03] Time-series of crustal deformation on Azuma volcano revealed by PALSAR-2 data
Keywords:SAR, Crustal deformation, Azuma volcano
Azuma volcano is an active volcanic complex in central Japan and comprises pyroclastic cones and/or volcanic craters aligning in the northwest-southeast direction. Several previous papers have reported increases of the volcanic earthquake and uplifts around Oana crater, one of the most active craters of the Azuma volcano in 2015 and 2018-2019, and sulfur combustion in 2020.
We applied multi-temporal InSAR analysis of ALOS-2/PALSAR-2 data observed in 2014-2020 for investigating the time-series of crustal deformation of the Azuma volcano. We report the spatiotemporal variety of line-of-sight (LOS) changes on Azuma volcano during 2014-2020 using PALSAR-2 data, which were acquired from both right-looking ascending and descending orbits.
Time-series of both ascending and descending LOS changes on Oana crater shows peaks of LOS shortening in 2015 and 2019, implying intermittent uplift. It takes about a year to reach the peak of LOS shortening, while about two years to reach zero for the 2015 LOS shortening. The northwest-southeast cross-section of the ascending LOS change revealed a peak of LOS shortening in 2015 on the northern rim of Oana crater and that in 2019 on the point of 200 m away from Oana crater for the northwest direction. We expect that the observed crustal deformation in Oana crater was driven by pressure change of the shallow hydrothermal system because the spatial extent of LOS changes is consistent with that of ground thermal activity and active fumaroles with steam/volcanic gas emission.
Acknowledgment: ALOS-2/PALSAR-2 data in this study are sharing among the PIXEL consortium, and are provided from JAXA under a cooperative research contract with ERI, the University of Tokyo.
We applied multi-temporal InSAR analysis of ALOS-2/PALSAR-2 data observed in 2014-2020 for investigating the time-series of crustal deformation of the Azuma volcano. We report the spatiotemporal variety of line-of-sight (LOS) changes on Azuma volcano during 2014-2020 using PALSAR-2 data, which were acquired from both right-looking ascending and descending orbits.
Time-series of both ascending and descending LOS changes on Oana crater shows peaks of LOS shortening in 2015 and 2019, implying intermittent uplift. It takes about a year to reach the peak of LOS shortening, while about two years to reach zero for the 2015 LOS shortening. The northwest-southeast cross-section of the ascending LOS change revealed a peak of LOS shortening in 2015 on the northern rim of Oana crater and that in 2019 on the point of 200 m away from Oana crater for the northwest direction. We expect that the observed crustal deformation in Oana crater was driven by pressure change of the shallow hydrothermal system because the spatial extent of LOS changes is consistent with that of ground thermal activity and active fumaroles with steam/volcanic gas emission.
Acknowledgment: ALOS-2/PALSAR-2 data in this study are sharing among the PIXEL consortium, and are provided from JAXA under a cooperative research contract with ERI, the University of Tokyo.