11:00 AM - 1:00 PM
[STT39-P02] Preliminary study on mudflow deposition area of the December 5, 2021 eruption of Sumeru volcano, Indonesia observed by PALSAR-2/ALOS-2
Keywords:PALSAR-2, ALOS-2, Mount Semeru, volcano, lahar, debris flow
On December 4, 2021, Sumeru volcano in Java, Indonesia erupted, and pyroclastic flows flowed along the the Rejari River (flowing southeastward at the foot of the volcano) and reached about 16 km from the crater. Due to the heavy rains that began the day before the eruption, debris flows and volcanic mudflows also flowed down to the same area at about the same time. As a result, a large amount of damage was caused, including workers who were digging for earth and sand in the river as well as the collapse of the Perah Bridge (a concrete truss bridge with a length of about 100 meters), which is a symbolic bridge in the area.
JAXA (Japan Aerospace Exploration Agency) conducted an emergency observation by the Synthetic Aperture Radar "PALSAR-2" aboard the "Daichi-2" (ALOS-2) at 1:51 a.m. on December 6 (JST). Using this data and the PALSAR-2 data taken at 1:51 a.m. (JST) on October 28, 2019 with the same orbit, the same orientation (ascending, right look direction), and the same polarization mode (HH, HV), JAXA estimated the above-mentioned sediment deposition area changed by lava flow, pyroclastic flow, and volcanic mud flow using polarization [1].
In this paper, by using Radar INterferometric Calculation tools (RINC) [2] with application to the same two PALSAR-2 images, we estimated sediment deposition and erosion area affected by pyroclastic flow and debris flow. We compared resultant images by SAR process with field survey photographs taken by Yachiyo Engineering Co. from 8th to 10th Dec. As a result, it was found that the SAR images give a good estimate of the upstream area with a large depth variation. It is also found that the area estimated by the polarimetric SAR image [1] and the images in this study could not extract at least the point of 0.6 m depth of sedimentation . Therefore, it exists issues of extraction of a small variation downstream area.
Acknowledgement
The data were provided by the Japan Aerospace Exploration Agency (JAXA) under a cooperative research contract with the Japan Meteorological Agency (JMA). We analyzed ALOS-2/PALSAR-2 data by using RINC and RINC GUI that are shared within the PALSAR Interferometry Consortium to Study our Evolving Land Surface (PIXEL), whose activity was supported by ERI JURP 2021-B-03 in Earthquake Research Institute, the University of Tokyo. Yachiyo Engineering Co., Ltd., provided us with field survey photographs. MLIT coordinated the provision of the phtographs between Yachiyo Engineering Corporation and us.
Reference
[1] JAXA ALOS Research and Application Project, Observation Result for Eruption of Semeru Volcano in Indonesia by ALOS-2, https://www.eorc.jaxa.jp/ALOS/en/library/disaster/dis_pal2_indonesia_eruption_20211206_e.htm (accessed on 14th Feb. 2022)
[2] Ozawa, T., Fujita, E. and Ueda, H., Crustal deformation associated with the 2016 Kumamoto Earthquake and its effect on the magma system of Aso volcano, Earth Planets Space, Vol.68, No.186, doi: 10.1186/s40623-016-0563-5, 2016
JAXA (Japan Aerospace Exploration Agency) conducted an emergency observation by the Synthetic Aperture Radar "PALSAR-2" aboard the "Daichi-2" (ALOS-2) at 1:51 a.m. on December 6 (JST). Using this data and the PALSAR-2 data taken at 1:51 a.m. (JST) on October 28, 2019 with the same orbit, the same orientation (ascending, right look direction), and the same polarization mode (HH, HV), JAXA estimated the above-mentioned sediment deposition area changed by lava flow, pyroclastic flow, and volcanic mud flow using polarization [1].
In this paper, by using Radar INterferometric Calculation tools (RINC) [2] with application to the same two PALSAR-2 images, we estimated sediment deposition and erosion area affected by pyroclastic flow and debris flow. We compared resultant images by SAR process with field survey photographs taken by Yachiyo Engineering Co. from 8th to 10th Dec. As a result, it was found that the SAR images give a good estimate of the upstream area with a large depth variation. It is also found that the area estimated by the polarimetric SAR image [1] and the images in this study could not extract at least the point of 0.6 m depth of sedimentation . Therefore, it exists issues of extraction of a small variation downstream area.
Acknowledgement
The data were provided by the Japan Aerospace Exploration Agency (JAXA) under a cooperative research contract with the Japan Meteorological Agency (JMA). We analyzed ALOS-2/PALSAR-2 data by using RINC and RINC GUI that are shared within the PALSAR Interferometry Consortium to Study our Evolving Land Surface (PIXEL), whose activity was supported by ERI JURP 2021-B-03 in Earthquake Research Institute, the University of Tokyo. Yachiyo Engineering Co., Ltd., provided us with field survey photographs. MLIT coordinated the provision of the phtographs between Yachiyo Engineering Corporation and us.
Reference
[1] JAXA ALOS Research and Application Project, Observation Result for Eruption of Semeru Volcano in Indonesia by ALOS-2, https://www.eorc.jaxa.jp/ALOS/en/library/disaster/dis_pal2_indonesia_eruption_20211206_e.htm (accessed on 14th Feb. 2022)
[2] Ozawa, T., Fujita, E. and Ueda, H., Crustal deformation associated with the 2016 Kumamoto Earthquake and its effect on the magma system of Aso volcano, Earth Planets Space, Vol.68, No.186, doi: 10.1186/s40623-016-0563-5, 2016