Comparing inversion results of geoelectric and seismic refraction data to construct a landslide model, a case study in the area of Tehran-North freeway

The sliding area under investigation is located in the central Alborz domain and situated at south of the north drift of Tehran with a slope to the north. The presence of this drift has caused the different units of tuff and conglomerate to be juxtaposed. It should be emphasized that electrical resistivity measurements are deployed along four profiles by collecting 31 electrical soundings in the study area. The maximum current has been transmitted up to a depth of 600 meters. The method of data collection is based on a Schlumberger array with the same station spacing. Electric sounding methods are used because of their good agreement with geological and well log information and core analysis. Upon geoelectric modeling, electrical resistivity cross sections of landslide surface were prepared. In order to extract a more accurate model from the landslide surface, refraction seismic was surveyed along three profiles, where the distance between the receivers (geophones) was 8 to 10 meters. By designing 9 seismic shots along each profile, the first arrival times were used for modeling. On each profile, the distances from the first geophone were assumed to be 30 and 50 meters. By inverse modeling of the first arrival travel time of rays along the path from the source to the geophone, the primary wave velocity model was imaged. In particular, focusing on comparing the inverted models of the geophysical methods, an accurate subsurface model of the possible landslide surface will be provided based on the models of electrical resistivity and seismic propagation velocity.