Sedimentology and determination of erodibility indices of marls of the upper red formation in Eyvanakey area

The studied region with 3750 km² is located in 65 kilometers in south-east of Tehran and 140 kilometers in west of Semnan. In this study, physical and chemical characteristics and engineering marl which are sensitive to erosion with various forms of Surface, Rill, Gully, and Channel Erosion have been investigated. It was taken 14 samples of marl surface with mostly Gully Erosion. The results of chemical analysis showed that the soil of this region is salin,alkali soils, from the viewpoint of engineering, soil samples within the SM, SW, SP, and SCM are considered. The granulometrie of soils showed that they are loamy to fine loamy. So they are susceptible to erosion. According to analysis to detect physical properties, chemical and mechanical engineering marl marked between amounts of salt, gypsum and lime are significant differences and these three factors can be an important factor in distinguishing erosion problems considered.