چکیده:
The phenomenon of subsidence as one of the geomorphic dangers has sustained a critical stage in some districts of the country in recent years. The frequent and sudden subsidence of the earth's surface is a phenomenon that happens under the effects of natural and artificial developments, gradual subsidence has a slow process and mainly takes place as the results of the extraction of liquids (water and oil) inside the earth. The continuation of subsidence in the long term can create irreparable damage to buildings, roads, bridges, pipelines and transmission lines. There are different methods, such as precise alignment, utilization of GPS (Global Positioning System) and remote sensing technology to monitor subsidence. The use of remote sensing technology in different earth sciences is very common because of the wide coverage of satellite images, the timeliness of the images and its low cost in comparison to terrestrial methods. One of the applications of radar interferometry is to display and control the displacements of the earth's crust due to factors such as earthquakes, landslides, and subsidence. The district studied in this research is an oil field located in the south of Ilam province. To meet the purpose of the study, the ALOS Palsar satellite image was used in the period from 2007 to 2010, as well as the DEM of the area that was prepared earlier, to monitor the subsidence phenomenon. SARSCAPE software was used in ENVI 4.8 platform to process the images, and by creating an interferogram and performing filtering operations, the average amount of subsidence was assigned as 3.4 cm per year.