Abstract

Landslide is a general term used to describe the down-slope of soil, rock and organic material under the influence of gravity. Several parts of northeastern region of India are vulnerable to landslide and moss movements. Nowadays, the Global Positioning System (GPS) technology has shown that it is capable to monitor sub-centimeter deformations of this ground movement. The main advantage of GPS sensors is that GPS requires no line-of-sight between the stations. This enables GPS to monitor the landslide even during unfavorable weather conditions either in real time or post-processing mode. However, the attainable accuracy of a GPS based system is limited by the satellite geometry and by systematic errors such as multipath, weak satellite geometry, etc. To monitor the landslide phenomena, it is imposed to represent the area under investigation by a number of points that are monumented durably. Some stations are used to define a stable reference frame and remaining stations are the monitoring points situated in the deformation area. In this way, the determination of the movement of the control stations is done relatively to the reference ones. Bakthang falls landslide selected for its movements. This paper therefore highlights an investigation of landslide motions to discover possible precursors of mass movement and periodical changing of landslide.

Key words: Landslide movement, global positioning system technology, Bakthang falls landslide.