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    1 - Production of Digital Elevation Model of Marvdasht Plain Using ENVISATASAR Radar Images with C-Wavelength Comparison with GPS Points and 1:25000 Topographic Maps of South Zagros Region
    Journal of Radar and Optical Remote Sensing and GIS , Issue 2 , Year , Spring 2021
    Digital Elevation Model is a continuous statistical representation of the earth by a large number of selected points with known coordinates of length, width and height. The use of three-dimensional models of the earth's surface has a wide range of applications in many a More
    Digital Elevation Model is a continuous statistical representation of the earth by a large number of selected points with known coordinates of length, width and height. The use of three-dimensional models of the earth's surface has a wide range of applications in many areas of research and implementation. It is high and the areas are level. All the resulting points have a height above sea level. Most GIS spatial analyzes use elevation data such as DEM. Using it, you can prepare a slope map and slope direction and perform various analyzes in three dimensions. Most of the time, DEM is also used as the bottom view of the maps. Elevation is used to extract height and height data. Major users (DEM) in the fields of civil engineering, surveying and photogrammetry, earth sciences, water resources management, military applications, telecommunications, urban planning digital land models as one of their information layers to achieve management, executive goals or produce new products using location-based. In this study, using images of ASAR ENVI SAT sensors in C band in the study area, we prepared a digital elevation model and then compared. And for verification, we compared this prepared model with the existing topographic maps at the scale of 1.25000 as well as the fixed points of GPS stations and also with the digital model obtained from (SRTM) in terms of elevation. The results of radar image processing in C bands of ENVI SAT ASAR sensor and its comparison with the data of the surveying organization indicate that the data processed from C band gives more favorable results and close to the ground control points, but considering Due to the correlation between GCP points and DEM obtained from topography, production conditions using satellite images are not favorable for the region. GCP captured the height points of radar images are in better and more favorable conditions according to Table (4) which shows the standard difference and this indicates the superiority of radar images for DEM production. Digital model comparison ratio with topographic points, shows the accuracy of satellite images in flat areas. In mountainous areas, due to the inclination of the points and creation of incoherence points, it is not continuous shadow and the level curve lines are intermittent. Manuscript profile

  • Article

    2 - Investigation of subsidence of different parts of Marvdasht plain using ENVISATASAR radar images with C-wavelength of South Zagros region
    Journal of Radar and Optical Remote Sensing and GIS , Issue 1 , Year , Winter 2022
    According to UNESCO, subsidence is the collapse or subsidence of the earth's surface that occurs on a large scale for a variety of reasons.Land subsidence is the gradual subsidence or sudden subsidence of the earth's surface. Land subsidence due to the movement of mater More
    According to UNESCO, subsidence is the collapse or subsidence of the earth's surface that occurs on a large scale for a variety of reasons.Land subsidence is the gradual subsidence or sudden subsidence of the earth's surface. Land subsidence due to the movement of materials underground is often caused by the removal of water, oil, natural gas or mineral resources from the ground by pumping, breaking parts or mining activities. As a result, deep cracks are created in the ground, well pipes are tilted, buildings are destroyed or cracked, and part of the well pipes are pushed out of the ground.In this article, using ENVISAT ASAR radar images, C band is related to the years 2006-2009 using ENVI5.3.1 software, SARSCAPE plugin. After performing PHASE TO DISPLACEMENT CONVERSION AND GEOCODING, we obtained the subsidence map. The subsidence obtained from the maps was between -18 to +12 related to agricultural plains, river banks, mountain falls and deposits due to rainfall and soil dissolution due to geological type. In the plains, subsidence has probably occurred due to the drop in groundwater. Consecutive droughts and uncontrolled groundwater abstraction and lack of management in abstraction in the future will be witnessed by severe crises in various regions. Manuscript profile