Ground Deformation Tracking over Mt. Baekdu: A Pre-evaluation of Possible Magma Recharge by D-InSAR Analysis

摘要

Mt. Baekdu, located in the northeastern Korean peninsula close to the Korea-China border, has been documented to have had a few destructive eruptions in history. Even though it has been dormant since the major eruption in 1702 A.D, the seismic activity in Mt. Baekdu has increased over the last few years. Together with the small-scale but constant earthquakes, other precursors, such as increasing geothermal activity in hot springs and emission of gaseous components, have also been identified. Since the reactivation of the volcano is suspected, we applied the Pifferential Inter Ferometric Synthetic Aperture Radar (D-InSAR) processing over Mt. Baekdu to detect possible topographic deformation caused by magma activities. To address the harsh environmental factors, such as water vapor, heavy vegetation canopy and steep slope around summit, for D-InSAR processing, the SB AS approach was applied to ENVISAT Advanced Synthetic Aperture Radar (ASAR) data together with ALOS PALSAR two pass D-InSAR analysis for the comparison and a clear deformation signal over the monitoring area was detected. In spite of the absence of direct measurements, the deformation in Small Baseline Subsets (SBAS) interpretation can be taken as the evidence for possible volcanic activity and employed as part of a warning system. Based on the findings revealed in this paper, it is strongly proposed that an intensive observation network covering the extent of Mt. Baekdu, together with international collaboration, is urgently required.