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Tabriz has special restrictions in its physical development. From the view point of geomorphology view, the city is faced with hazards for developing, such as: earthquakes, mass movements and floods. Geomorphologic hazards of the city have been reviewed in this paper. The aim of this study is classification of stable and unstable regions of Tabriz. For attaining this aim, Geographic Information System (GIS), Digital Elevation Model (DEM) and Normalized Difference Vegetation Index (NDVI) have been used. Landsat satellites images (type TM) have been used for increasing the accuracy of needed data. Mixing all data in GIS environment generated the maps of limitations for city development and of hazardous areas of the city. Maps can be classified in two groups: a) The map of ruggedness of the city and its suburbs, b) The maps of geomorphologic hazardous areas of the city for developing such as: the map of hydrological hazards, land-cover limitations, instabilities of lithological conditions and faults distribution in the city and its suburbs. The maps are applicable in the development planning of the city. The results showed that banks of Mehraneh Roud, and also Baghmisheh and Valiasr areas are considered hazardous area in Tabriz. However, earthquakes hazards are equal in the city and suburbs because of sub-faults distributed in all area of the city.

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Many of well known Iranian hydrocarbon reserves are concentrated in the anticlinal oil traps of the Asmari Formation. Fractures are too important in fluid flow simulation, because of their impacts on anisotropy and heterogeneity of the Asmari carbonate reservoirs. In order to fracture network modeling of the Asmari reservoirs, it’s necessary to have information about many parameters that most of them can not be got from the well data. Therefore, the extracted data from the remote sensing studies of the Asmari outcrops can be as a basis for determining these parameters. The remote sensing imagery is one of the main techniques available to geologists for locating and extracting fracture systems. The Kuh-e Asmari anticline in marginal part of the Zagros Fold-thrust belt has been selected for remote sensing studies of the faulting/ fracturing systems in the Asmari outcrops. In this study, Landsat (ETM+) images, ASTER images (with high spectral resolution), IRS-PAN images (with high spatial resolution), and a detailed Digital Elevation Model (with scale 1:25,000) covering the Kuh-e Asmari anticline were used. The geometrical correction, data processing and image enhancement of the satellite images were carried out in ER Mapper 6.4. Furthermore, to improve the fracture study, some 3D models were made by draping satellite images on the DEM. In this study, many data were extracted about the fracture traces. The results were delivered as figures,maps, 3D models and statistical graphs. The statistical and structural analysess of the Kuh-e Asmari anticline showed faulting/ fracturing systems which have been formed by different mechanisms, and in different times. The results of this study can be used for fracture pattern modeling and prediction hydrocarbon flow in the Asmari reservoirs.

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Digital Elevation Models (DEMs) are one of the most important inputs in most rainfall -Runoff models and also in deriving watersheds geomorphological characteristics. One of the most important issues that should be taken into account when using DEMs in rainfall runoff modeling is the effects of DEM source on the results of the models. At present time, radar based DEMs are attracting a considerable attention in many earth related fields. Currently, there are several sources such as: Shuttle Radar Topography Mission (SRTM) data and the advanced space thermal emission radiometer (ASTER) that due to ease of access and free of charge, have an important role in hydrological modeling and the extraction of geomorphological parameters of catchments. This paper addressed the effects of different DEM sources: ASTER, SRTM, and 1:50000 topographic based DEM on the topographic index and performance of a semi- distributed model, called TOPMODEL. The obtained results indicated that by increasing DEM cell size, disregarding its source, the topographic index inceased. Also, it was illustrated that for all cell sizes other that 30 m there was no difference between the results of ASTER and SRTM DEM. Such a coincidence was observed for TOPO DEM for cell sizes larger than 100 m, as well. Results showed that the effect of data resolution on the average daily discharge, average saturation deficit of basin and the average distance to water table level is not meaningful. In daily discharge simulation, the performance of TOPMODEL when using the TOPO DEM ,based on the NASH- SUTCLIFFE efficiency index, was the highest and for the SRTM DEM was the lowest. In flood simulation, upto 200 m resolution, TOPMODEL efficiency was constant disregarding the DEM source, while its efficiency reduced for cell sizes greater than 200 m in all conditions. It was illustrated that by increasing the cell size, surface runoff contribution to total runoff, in contrast to subsurface flow, increased. Furthermore, For all of the sources, increasing the DEM cell size, incresesd the surface runoff contribution and decreased subsurface flow. The percent of surface flow simulated by the model when implementing the DEM of SRTM is the highest. According to achieved results, the percentage of simulated surface runoff from SRTM DEM was higher than the other two sources. It was observed that the number of cells of low slope in SRTM DEM is greater than the other sources, which was concluded as the main reason for this issue. Reducing the slope of a cell could reduce its potential to carry subsurface flow, which in turn could increase the cell potential to be saturated. It was concluded that DEM different sources effects on average saturation deficit and water table is negligible, and these ouputs of TOPMODEL is mainly affected by DEMs cell size. Finally, this important conclusion was drawn from the present research that the information content of ASTER DEM is nearly similar to TOPO DEM and higher than SRTM DEM; therefore, between satellite based DEMs, it is more convenient to use ASTER DEM for rainfall runoff modeling.