Investigating the erosion of formations and marine units using BLM agent (Case study: Varamin County)

: Based on the stratigraphic information obtained from the combination of stratigraphic columns in geological maps with a scale of 250,000: 1 and sometimes 1: 100000, the four sheet of Varamin, Tehran, Damavand, Semnan and field survey were determined. There was a general absence in the area. all Marl formations and units, which specifically include three shale units, Marl gypsum, sandstone, brown and red Marl unit with interbeded sandstone, which belong to the Senozoic period and in the northeast, east, south and south. The southwest is scattered. From the distribution of Marl, 29 samples of Marl soil were chemically and physically tested, and because the evaporative sediments were distributed in most areas, the results did not show a significant difference. The erosion of the region, relying on the BLM factor, had a high numerical value and showed very erosion. Due to the solubility of salt and also rarely gypsum and lime and their capillary properties, the density of vegetation is very low and the dominant vegetation type was itchy and boneye Alhagi camelorum and Aeluropus lagopoides and the species of Bromus tectorum , Hordeum marinum, Peganum harmala, Artemisia sieberi, Prosopis stephaniana, Phragmites australis, Seidlitlia rosmarinus, Capparis spinosa, Chenopodium murale, Convolvulus arvensis, Tamarix sp, Haloxylon sp, Pteropyrum aucheri, Salsoa a species with limited distribution in the region.