The Role of Kerend Fault on Evolution of Folds in North Western Part of Zagros Case study: Rijab Syncline

Kerned fault with 45 km length and over thrust feature is one of the most important morphological structures of the North West part of folded Zagros around Sare- Pole- Zahab Occurrence a number of 20th centaury earthquakes along this fault indicates that this fault is active now.The most important work of Kerend fault is the displacement of calcareous-dolomite layers of Zagros around Rijab syncline area from north east toward south west, inclination of Rijab syncline structure toward south west and occurrence of diffraction at the south west wing of Rijab syncline from its middle. Diffraction has occurred within tension-bending process and consequently the fragments due to breakage have been moved rotary. The result of this event was formation of a series of longitudinal and transversal faults which cut calcareous-dolomite layers of Rijab in different directions. Results of this investigation which is plotted by the two comparative- analytic and field research method, means by comparing and interpreting of topographic maps with hydrographic and linear, and surveying the geology profiles, interpretation of aerial photos and also local observations showed that evolution of Rijab syncline in this fault system not only has caused it to be raised as a natural castle, but also has created the situation of forming almost it’s all visual features including torrents, falls, gorge and deep valleys. Rijab syncline for having such landscapes has changed in to an important centre of tourism in Kermanshah province.