Landslides Investigation in Gado-Gado Hill South Padang District Using Geodetic GPS As a Reference for Landslide Disaster

Abstract

South Padang District is a landslide-prone area. Almost 70% of South Padang District is hilly. This study uses GPS Geodetic with 10 measurement points along Siti Nurbaya Street to Bukit Gado-Gado Street. Based on observations, the moving average is 16.29251 mm. The largest movement occurred at point 7, namely 24.69818 mm in the azimuth direction. While the smallest movement at point 5 was 8 mm in the azimuth 90° direction. The horizontal movement was divided to the north and south. Point 7 experienced the largest change in vertical position, namely 25.5 cm and point 8 experienced the smallest change in vertical position, namely 2.8 cm. The majority of the movement is in the upward direction, only one point has a downward movement, namely at point 9 of 3.7 cm. Based on the data obtained, the highest landslide velocity occurred at point 7. This movement has a value of 0.148 m/year in the horizontal direction and 1.530 m/year in the vertical direction. The smallest horizontal velocity occurs at point 5 which is 0.048 m/year and the slowest movement direction occurs at point 8 and above at 0.168 m/year.