Transient Reactivation of Kara-Bogaz-Gol Coastal Landslide, Modulated by Hydrological Forces Captured Using InSAR (Turkmenistan)

This paper presents a hydrologically modulated transient motion of world's largest active landslide occurring along the western shore of the Kara-Bogaz-Gol (KBG) lagoon of the Caspian Sea (CS) using Interferometric Synthetic Aperture Radar (InSAR) data. Here a dataset of Sentinel 1A/B IW SAR imagery acquired on ascending and descending modes between 2014 and 2020 has been processed to analyze the present-day evolution of this giant coastal landslide. The results shows that the eastern bank of the KBG lagoon (25x5 km) is horizontally sliding toward the lake at a rate of 25 mm/yr. The time series analysis reveals week-long accelerating slip events when the KBG reservoir water level reached its seasonal maximum. This study presents new information on the potential roles of the hydrological forces modulated by sea-level rises on the ancient landslides which originated during successive CS transgressions in the Late Glacial.