Slope Stability Analysis of the Southwestern Limb of Kosret Anticline in Dokan, Northeastern Iraq

The stability of the rock slopes was studied on the southwestern limb of the Kosret Anticline in the Dokan Area in northeastern Iraq to analyze and indicate the danger of rock mass failures along the public street linking Dokan and Quesangaq, Erbil and the road which link between the city and the residential neighborhood of Dokan Lake, as well as the revealing and the analysis of the risk of landslides in the slopes and rocks detectors of exposed rocks of the formations in the study area. The stereographic projection was used in the analysis and classification of the rock slopes. This study has shown that the failures of rocks are fall and day lighting bedding plane. The factors that affect the stability of the slopes were assessed. This research mainly focuses on identifying the types of collapses along the rocky slopes and the factor that affects the instability of the studied slopes. It was found that it is the direction slopes and the interruption geometry. Different treatment methods have been proposed for the studied rock base on the rock slope analysis. The expected failure types that may occur along the road are plane sliding, rock fall, toppling, and probably the failure type in the future may be planner sliding due to the angle of the friction comes to zero degree. The rocky slopes along the road require constant monitoring due to their hazardous conditions. Where it was found that the attitude of the joints and their frequency with the relation between the attitude of the slopes and the rock beds played an important role in the failures, as well as the weak rocks of the Marl layers of the Shiranish, Kometan and Tanjero formations play a key role in responding to weathering and erosion factors that increase the failures of rock slopes