地理と自然災害のジャーナル
オープンアクセス

概要

Space Geodesy for Deformation Analysis of 2019 Mirpur Earthquake, Western Himalaya

Somalin Nath1*, Ashutosh Venkatesh Prasad2

Differential Interferometric Synthetic Aperture Radar (DInSAR) observations conducted in this study have provided crucial insights into the earthquake-induced deformation patterns. The analysis indicates that the majority of deformation is concentrated in the zone between the NE-SW (North East-South West) trending Samwal Fault and the NW-SE trending Jhelum Fault. This concentration of deformation aligns with the known tectonic features of the region. Furthermore, the phase profile obtained from DInSAR data reveals specific details about the nature of ground displacement. South of the East-West trending Samwal Fault, an upliftment of 0.27 meters is observed. In contrast, on the Northern side in the Line Of Sight (LOS) direction, there is evidence of subsidence, with a downward displacement of 0.16 meters. These findings underscore the localized nature of the earthquake-induced deformation and highlight the significance of the underlying fault systems in governing the observed ground movements. In summary, the 2019 Kashmir earthquake stands out for the severity of building damage relative to its magnitude. The study's findings emphasize the importance of considering local geological and tectonic factors in assessing seismic hazards. The complex tectonic setup, influenced by major faults like Samwal and Jhelum, contributes to the region's heightened seismic activity. The detailed insights gained from DInSAR observations aid in unraveling the intricacies of ground deformation patterns, enhancing our understanding of earthquake dynamics in the Himalayan Belt and informing future seismic risk mitigation strategies. The 2019 Mw 5.6 Kashmir earthquake, despite its relatively moderate magnitude, had a pronounced impact on the foothill regions of the Himalaya, resulting in substantial damage to buildings. This phenomenon has intrigued researchers due to the seemingly disproportionate intensity of damage compared to the earthquake's magnitude. A comprehensive analysis suggests that the variance in damage intensity is attributed to several factors, including differences in sediment load, underlying geological structures, and the ongoing tectonic activity in the region. The area's tectonic setting is complex, contributing to its classification as one of the seismically active regions within the expansive Himalayan Belt. Two major faults, namely the Samwal Fault and Jhelum Fault, play a pivotal role in shaping the tectonic landscape of the area. The interplay of tectonic forces along these faults has modified the geological features, creating a dynamic environment prone to seismic activity.