A study of landslide deformation fields with a digital correlation method

Landslides are a form of geological disaster. Landslide development around the Three Gorges Dam is affected by many factors, such as the dam’s water storage cycle, flood discharge and precipitation. In this work, we investigated the Woshaxi landslide in Zigui County, Hubei Province. We gathered landslide images from April to May 2015, using digital cameras to observe the landslide surface. The landslide images were analyzed with a digital correlation method to obtain a landslide deformation field. The overall displacement was distributed non-uniformly, with displacements of up to 50 cm. We found landslide movement is a non-uniform and non-rigid body motion. By integrating the speckle method, grayscale feature search and other related methods, we not only succeeded in dealing with landslide data at various scales and levels, but also solved problems such as the registration of collected images and peering of gray levels. We calculated the displacement variation and direction of all landslide points and obtained the landslide displacement distribution. The method’s indoor calibration test error was within an acceptable range. This method is a good candidate for landscape monitoring due to its convenient operation, low cost and ability to extract useful information from a huge amount of data.