PENGEMBANGAN TEKNOLOGI MONITORING GEOLISTRIK TIME-LAPSE UNTUK MEMANTAU DAERAH RAWAN LONGSOR DI KOTA PADANG DENGAN MENGGUNAKAN METODA GEOLISTRIK TIME-LAPSE RESISTIVITY INVERSION KONFIGURASI WENNER

Abstract

ABSTRACT

Lately landslide disasters often hit the city of Padang. In order for this landslide problem can be adequately addressed by the parties concerned it is necessary to comprehensively research and see the picture of the physical properties and structure of the subsurface rocks in areas prone to landslides. Until now, how the image of the physical properties and structure of the subsurface rocks in Padang has not been disclosed. This research aim to identify the presence of sliding plane in areas prone to landslides. Data collection was performed at the Bukit Lantiak who entered the Seberang Palinggam Village, South Padang District, city of Padang. Data obtained by using the Wenner configuration are processed with the help of RES2DINV software in the form of a cross section 2D models that have different colors. Each color indicates the range of values of certain types of resistivity. The interpretation of data to Track 1 is as follows. Tracks 1 is located at coordinates 0.000 58’ 3.7” S and 1000 22’ 5.6” E until 0.000 58’ 3.9” S and 1000 22’ 10,1” E. Sounding point is at coordinates 0.000 58’ 3.9” S and 1000 22’ 10,1” E. First track length is 315 m with an electrode spacing of 5 m. Based on the resistivity values obtained on Track 1 is identified, there are 4 types of rock constituent that is Clay, Sandstone, Limestone, and Andesite. Interpretation of the results showed in Track 1 are sliding plane. Geoelectric Time- Lapse Resistivity Inversion Method done for two sets of data, geoelectric measurements at an early stage and second stage. The magnitude of change in resistivity to both sets of data on average almost the same at all points of measurement which is around 50%, except at certain points which indicate a greater percentage.

Keywords: Landslide Disasters, Physical Properties and Structure of The Subsurface Rocks, Geoelectric Resistivity Method Wenner Configuration, Sliding Plane, Time-Lapse Resistivity Inversion