The engineering geological investigation of the landslide area at the left slope of the Kürtün dam (Kürtün-Gümüşhane)

In this study, the engineering geological investigation of the lanslide area at the left slope of the Kürtün Dam (Kürtün-Gümüşhane) was carried out.In the scope of this study, 1/25.000 scaled geological map of the surrounding area and 1/2.000 scaled engineering geological map were done. It was determined that the basement rocks at the landslide area consist of diabase and granodiorite.Geodetical studies were carried out to determine the deformations at the landslide area. Resistivity measuments were carried out to determine the depth of the talus. 7 boreholes 350 meters in length were dirilled to have detailed informations about talus and basement rocks. Inclometer measuments were carried out to determine the depth of the slip surface.Undistributed soil samples were taken with the sampling tubes from the study area and index properties, consistency limits, shear strength and grain distribution of the soil were determined.Using all of the obtained data from field and laboratory studies, the stability of the landslide area was investigated by using simplified Bishop and Janbu methods in the ?Slide? limit equilibrium analysis program.As a result of the back analysis, it was determined that the lanslides at the left slope of the Kürtün Dam are backward-moving and their slip surface are circular and combined type.