Change Analysis of the Stenungsund Landslide Using UAV and Airborne LiDAR Data

Abstract

Airborne LiDAR (Light Detection and Ranging) is an important tool to analyze landslides in remote sensing surveys and can produce high resolution DTM’s of the ground surface. By applying a multi temporal survey, it can provide information about the size, height difference and geomorphology of the landslide to better understand its kinematic and how the surface has changed. In southwestern Sweden, Quick clay landslides is common and can cause severe damage to society which means that it is important to investigate these types of events when they occur. The aim of this project is therefore to analyze and understand the movement of a recent major landslide, the Stenungsund landslide, by comparing UAV and airborne LiDAR data from before and after the landslide event. This is carried out by using different analyst tools in the GIS software QGIS that allows to create different models and maps of information regarding elevation difference, morphology and displacement. Fieldobservations were also conducted to support the remote sensing survey. The Results from the change analysis indicated that most of the material from the landslide has moved downhill from the upper part of the slope to the lower part and passed slope in a northwestern geographic direction. Through the interpretation of the morphology, two major flows may have caused the downhill movement due to the positioning of ridges and heaving zones. This resembles a translational progressive landslide. The study was able to understand and interpret how the landslide has moved and the extent of it, thus, future surveys have great opportunities to use UAV and airborne LiDAR in similar landslide investigations.