3D estimation of strain and velocity in Bududa district using GNSS

Abstract

Landslides are defined as ‘the movement of a mass of rock, debris or earth down a slope’ and mostly constitute small, but sometimes frequent events affecting millions of people worldwide(Cruden, 1996). They are part of very many natural hazards that have affected people from time memorial others including earthquakes, avalanches and floods((Acar, 2010). Landslides in particular have been recorded for several centuries in Asia, Europe and Africa(De Graff et al., 1989) affecting millions of people worldwide(Mertens et al., 2016). Landslides monitoring studies are carried out mainly on one of the two main stages that is to say the strain and deformation stages. The strain stage is the stage where the actual ground deformation has not yet happened but the stress factors causing the deformation are present and thus deformation may happen any time. This helps to provide useful information on which areas are stressed the most and hence remedies are put in place. This report discusses the monitoring of these landslides using GNSS. It also presents strain tensors, rotation tensors, dialatation tensors that show the crustal movements during the time of GNSS observations. These were computed using a software called Geostrain which is an open source software running in MatLabs software.The report also shows the velocity motion of the district calculated using Trimble Business Center software.