عنوان مقاله [English]
The gradual and sudden subsidence of the earth's surface is a phenomenon that takes place under the influence of natural and artificial developments. Injuries caused by these types of falls can sometimes be catastrophic. In contrast, gradual subsidence has a slow process and mainly occurs due to the extraction of liquids (water and oil) in the ground. Continuation of subsidence in the long term will lead to significant damages, especially from an economic point of view. Among the damages that occur due to the gradual subsidence of the land are the damages that are caused to buildings, roads, bridges, pipelines and power transmission lines. Excessive extraction of groundwater leads to land subsidence. Due to its proximity to Tehran and Karaj and its special location, Eshtehard region has special morphological perspectives. In this research, using Landsat 7 satellite images and 1:25,000 topographic maps and 1:100,000 geological maps, arcGIS and ILWIS software, documentary and field studies, and statistics of the underground water level of Eshtehard city wells in the period from 79 to 83 Geology and rock type and type of geological formation of the studied area and the desired maps have been prepared, the results show that the existence of aqueduct furnaces and the reduction of the underground water level due to excessive use and the existence of evaporation formations in this area are among the most effective factors of land subsidence. It is within the scope of the study. The issue of subsidence is of great importance to engineers and planners today (Guderzinejad, Shapur, 1378 p. 310.), and the results of studies indicate that the development process of Eshtehard city has caused environmental problems and problems. Due to the tectonic dynamics of the region, damaged residential buildings are at risk.