Determination of landslide problem using electrical resistivity tomography and multi channel analysis of surface waves

Landslide is one of the most important problems in geology, and it is affected to humanity as a hazard. The landslide sites in the Earth are increased according to urbanization day by day. Geophysical surveys have great majority in landslide investigations. Particularly, the resistivity methods have been used in landslide since many years. Electrical resistivity tomography (ERT) method is produced effective results to determine the geometry and the characteristics of landslides. However, the multi channel analysis of surface waves (MASW) technique is rarely used in the landslide investigations. In the scope of this thesis, ERT and MASW techniques were applied in Avcılar region, which is one important landslide sites in İstanbul. According to these surveys, the geometry and the characteristic of the landslides was defined in the slided areas. In particular, the MASW technique was produced important results to determine the geometry of landslide and the geological units in means of Vs velocity. In addition, the soil properties of slided areas are determined used by geotechnical analyses carried out using Vs velocities. The soil analyses pointed out that the slided area and its surroundings are not suitable for the settlements. In addition, the results of drilling studies showed that geophysical data are mostly successful in the determination of subsurface and landslide character.