Assessing the effective factors on water erosion in Marly deposits of Mishan and Aghajary formations in the west of Bandar Abbas

By knowing of the effective parameters on erodibility of marl deposits, can be improve landuse and reduce erosion and sediment yield. At present research, Assessing the effective factors on water erosion in the marly area, Mishan and Aghajari formations in the west of Bandar Abbas, is studied. For this purpose, according to lithology map, general slope and landuse, determine the sampling points and using a portable rainfall simulator type kamphorst in the desert, the runoff and sediment yield were studied. 18 test of rainfall with intensity 6/74 mm per minute on the Sampling points, with at least 3 replications in Mishan and Aghajari marl units in the west of Bandar Abbas at slopes 10 and 20 Degree in both surface and gully erosion was conducted and 18 samples of runoff and sediment were taken. 18 sediment samples were collected for physical and chemical analysis All of which were analyzed for granulometry. Chemical properties include determining the parameters of electrical conductivity (EC), degree of acidity (pH), organic matter (OC), cations and anions solution, sodium absorption ratio (SAR), lime, gypsum and exchange capacity cation (CEC). Atterberg limits of 6 sample was measured. The results showed that in both Mishan and Aghajari formations, the mud content of the samples in surface erosion is more than gully erosion shape. In surface erosion shape, Mishan marl has silt and clay particles more than Aghajari marl, therefore Mishan marl is more than résistance to erosion and produce less sediment. Based on rainfall tests  in marly area, inherent erosion of marls of Mishan and Aghajari are 2/76 and 5/27 respectively compare to tolerance erosion rate. In this study, for the first time, the ratio of sand content to sum of clay and silt content as standard physical indicators for the separation of two surface and gully erosion forms was presented from each other. Above mentioned index in Marls with gully erosion is more than which with surface erosion forms. The liquefaction potential study subjects showed that the samples with liquefaction capacity, the gully erosion development.