tehran geosystem and its significance in urban development essence

abstract geosystems or geomorphic systems include terrain structure with processes interactions that work as alone or common and create a series of terrain unites. geosystem elements consist of lines, points, surfaces, and volumes. the ways of relationships between the elements form spatial structure identity. the elements prepare spaces for different land uses, when they are located in ratio to each other. the study has done with terrain analysis approach, and also with historical evolutions analysis, and archeology pattern of ancient civil on the tehran geosystem. doing the research, we have used of topography and geology maps, dem produced by radar with 20 meter resolutions, aerial photograph, land sat satellite image, and also google earth. results the study show that the results show that tehran metropolitan has spread out on a geosystem that could be called glaci-fluvial, the space has been made by ice and water processes in quaternary as external dynamics to form suitable habitats. also, tectonic, especially faults displacement, in the north and south of teheran geosystem, has affected on the creation of topography and dispersion of the spaces. therefore, tehran geosystem consist of boundary, structure, function, hallway, direction, unique historical evolution, totality and convergent and special climatic characters. the factors in relation to each other have formed geomorphic elements that could follow as urban structure pattern, and land use. understanding of the elements in a geosystem approach, and with a unique essence is very important, because compatibility and coincidence of urban structures on the elements lead to stable and organic urban, and could be come to rest as a turning point in urban design and planing