ARABIAN JOURNAL OF GEOSCIENCES, vol.14, no.20, 2021 (SCI-Expanded)
A large landslide was triggered after a heavy rainfall in Egridere district (Izmir/Turkey) on 13 February 2019. This catastrophic event destroyed about 10 houses and animal shelters. After the landslide, it is emerged that it is necessary to characterize and identify immediately the subsurface layers of the area by geophysical and geological investigations. This study is conducted in two adjacent sites: the Egridere landslide area and a landslide susceptible area. The current study characterizes these two areas by the application of geophysical methods together with geological observations. Due to the very disturbed surface morphology, geophysical studies have just been conducted out the adjacent landslide susceptible area. However, before the occurrence of the event, the previous study covering Multichannel Analysis of Surface Waves and borehole data in the landslide area was obtained and interpreted in this study. Integrated Electrical Resistivity Tomography and Seismic Surface Wave measurements have been performed in the landslide susceptible area, and their results were correlated with geological findings. Resistivity sections of the measuring profiles revealed the slope wash material with high water content and andesite unit. Thus, the failure surface related to the landslide susceptible area was defined by the interpretations of the resistivity results. Seismic surveys were primarily used to obtain unit boundaries up to 40-m depth. We observe that outputs of both geophysical methods yield compatible results according to the physical properties obtained from these methods. Consequently, it can be expected that the slope wash unit observed in the landslide susceptible area may cause a landslide and the models obtained in this study should be used to prevent future damages that may arise due to the similar hazards.