Slope stability modelling and landslide hazard zonation at the Seymareh dam and power plant project, west of Iran

10 Jan 2017

The Zagros Mountains Range is an important structural unit in south western Iran and accommodates a significant portion of the 2.5 cm/year convergence between Arabia and Eurasia. This structural unit includes folds, thrusts, strike-slip faults and salt diapirs. There is evidence of past failures in the area, probably some 11,000 years ago. In the order of 30 million cubic metres of rock debris was moved from the Kabir Kuh Anticline as well as rock failures from the Ravandi Anticline. Investigations indicated 4.5 m of landslide/rock fall debris underlying about 28 m of lake deposits and 5.5 m of recent river alluvium upstream of the Seymareh Dam area. The direction of the Seymareh River bed was displaced by about 1,000 m to the northeast, forming a sharp river meander near the entrance to the gorge of the Ravandi Anticline where the Seymareh Dam is being constructed. The paper reports the rock slope instability modelling, kinematic analysis of slope faces and landslide hazard zoning undertaken.