Geophysical survey of landslide movement and mechanism in Gorontalo Outer Ring Road, Gorontalo

• Published in: IOP conference series. Earth and environmental science 2020-11, Vol.589 (1), p.12008
• Main Authors: Usman, F C A, Manyoe, I N, Duwingik, R F, Kasim, D N P
• Format: Article
• Language: English
• Subjects: Electrical resistivity; Fractures; Geophysical surveys; Geotechnical fabrics; Landslides; Landslides & mudslides; Limestone; Retaining walls; Rockslides; Surface water; Water absorption; Water infiltration; Weathering
• ISSN: 1755-1307; 1755-1315
• DOI: 10.1088/1755-1315/589/1/012008

Gorontalo infrastructure development focus on improving transport efficiency through the development of Gorontalo Outer Ring Road (GORR). The Government has set the cost 750 billion rupiahs for GORR and planned will be completed by 2019 but constrained by landslides. This research aims to reconstruct and identify the type and mechanism of a landslide at GORR. The result of this research is landslide type and mechanism in the research area. The method used is 2-dimensional electrical resistivity sounding with Wenner-Schlumberger configuration. Landslide mechanism is analyzed based on the resistivity value table on Vingoe resistivity value supported by geological data. Based on geophysical data, subsurface conditions showed blocks of limestone with a resistivity value about 132 Ωm and marked red-purple colors. These blocks of limestone interpreted as the result of the weathering process and buried in weathered clastic limestone. Landslide movement type is sliding movement and concluded as a rockslide. There is a potential for subsurface landslide blocks occur caused by the weathering process on fractures in the research area. The future prevention steps are by increasing the surface water absorption by planting in the geotextiles or prevent water infiltration in the landslide area. In addition, manufacturing retaining wall is also required.